Costatoria kobayashii (Kambe)
1951. Myophoria goldfussi Alb. in Bittner var. kobayashii Kambe, p. 54, pl. 4, fig. 7.1960. Costatoria kobayashii (Kambe): Nakazawa, p. 52, pl. 6, figs. 10-20.
Type. —Lectotype here designated (Kambe, 1951, pl. 4, fig. 7) (UMUT MM6477) from Gujo, Oe, Kyoto Pref.
Age and distribution. —Upper Permian. Gujo formation in Maizuru zone.
Remarks. —This was originally described as a Triassic form.

Costatoria goldfussi (Alberti)
1972. Costatoria goldfussi (Alberti): Tamura, p. 69, pl. 1, figs. 17-20.
Age and distribution. —Ladinian or Carnian. Konosé group in Yamae area. This species has been reported from central and south Europe.

Costatoria multistriata (Kobayashi and Ichikawa)
1954a. Myophoria multistriata Kobayashi and Ichikawa, in Ichikawa, p. 59, pl. 7, figs, 2-4.
Type. —Holotype (UMUT MM5427) from Arai, Itsukaichi, Tokyo Pref.
Age and distribution. —Triassic (precisely unknown). Arai formation in Itsukaichi area.

Myophoria sp. cf. M. intermedia (Schauroth)
1972. Myophoria sp. cf. intermedia (Schauroth): Tamura, p. 68, pl. 1, figs. 23, 24.
Age and distribution. —Ladinian or Carnian. Konosé group in Yamae area.

Gruenewaldia decussata (Münster)
1972. Gruenewaldia decussata (v. Münster): Tamura, p. 70, pl. 1, figs. 1-13.
Age and distribution. —Ladinian or Carnian. Konosé group in Yamae area. This species has been known from Alps.

Gruenewaldia sp. cf. G. elegans (Dunker)
1972. Elegantinia sp. cf. elegans (Dunker): Tamura, p. 71, pl. 1, figs. 21, 22.
Age and distribution. —Ladinian or Carnian. Konosé group in Yamae area.

Neoschizodus (Neoschizodus) tangoensis (Kambe)
1951. Myophoria tangoensis Kambe, p. 51, text-fig. 1, pl. 4, fig. 1.-compare 1957. Myophoria tangoensis Kambe: Kambe, p. 14, text-figs. 9, 10, pl. 1, figs. 23, 24.
Type. —Holotypy by monotypy (UMUT MM6471) (not "cotype" as originally designated) from Mirokudani (Shidaka), Maizuru, Kyoto Pref.
Age and distribution. —Skytian. Shidaka group in Maizuru zone. Some authors have regarded this group as Upper Triassic.

Neoschizodus (Neoschizodus) sp. cf. N. (N.) laevigatus (Zieten)
1951. Myofhoria shidakensis Kambe, p. 51, pl. 4, fig. 2.-1951. cf. Myophoria laevigata (Zieten) var. elongata Phil.: Kambe, p. 53, pl. 4, fig. 5.-1951. cf. Myophoria laevigata (Zieten) var. rotunda Phil.; Kambe, p. 53, pl. 4, fig. 6.-1957. Myophoria tajimensis Kambe, p. 6, text-fig. 2, pl. 1, figs. 1-4.-1957. Myophoria laevigata (Zieten): Kambe, p. 7, text-figs. 3, 4, pl. 1, figs. 5-7.-1957. Myophoria cf. laevigata (Zieten): Kambe, p. 9, text-fig. 5, pl. 1, figs. 8-11.-1957. Myophoria laevigata (Zieten) var. miharaiensis Kambe, p. 10, pl. 1, fig. 12.-1957. Myophoria cf. laevigata (Zieten) var. elongata Phil.: Kambe, p. 11, text-fig. 6, pl. 1, figs. 14-17.-1957. Myophoria cardissoldes (Zieten): Kambe, p. 12, text-figs. 7, 8, pl. 1, figs. 18, 19.-1957. Myophoria aff. nakajimensis Ichikawa: Kambe, p. 13, pl. 1, figs. 20-22.-1957. Myophoria shidakensis Kambe: Kambe, p. 15, pl. 1, figs. 25, 26.-1960. Neoschizodus cf. laevigatus (Zieten): Nakazawa, p. 56, text-fig. 2, pl. 6, figs. 21-32.
Type. —Holotype by monotypy of Myophoria shidakensis (UMUT MM6472) (not "cotype" as originally designated) from Mirokudani (Shidaka), Maizuru, Kyoto Pref. Holotype of Myophoria tajimensis (GSJ F-3148) from Miharaiyama, Oya, Hyogo Pref. Holotype of Myophoria laevigata var. miharaiensis (GSJ F-3159) from Miharaiyama, Oya, Hyogo Pref.
Age and distribution. —Skytian. Miharaiyama group and Shidaka group in Maizuru zone. Some authors have regarded these groups as Upper Triassic.

Neoschizodus (Neoschizodus) nakajimensis (Ichikawa)
1949b. Myophoria nakajimensis Ichikawa, in Kobayashi and Ichikawa, p. 180, pl. 6, fig. 4.
Type. —Holotype (UMUT MM5227) from Nakajima, Sakawa, Kochi Pref.
Age and distribution. —Carnian. Kochigatani group (lower part) in Sakawa area.

Neoschizodus (Neoschizodus) dieneri (Ichikawa)
1949b. Myophoria dieneri Ichikawa, in Kobayashi and Ichikawa, p. 181, pl. 6, fig. 1.-1949b. Myophoria dieneri var. longa Ichikawa, in Kobayashi and Ichikawa, p. 181, pl. 6, fig. 3.-1949b. Myophoria umenokiensis Ichikawa, in Kobayashi and Ichikawa, p. 183, pl. 6, fig. 6.
Type. —Holotype (UMUT MM5223) from Umenokidani, Sakawa, Kochi Pref. Holotype of Myophoria umenokiensis (UMUT MM5229) from the same locality. Holotype of Myophoria dieneri var. longa (UMUT MM5225) from Nakajima, Sakawa, Kochi Pref.
Age and distribution. —Carnian. Kochigatani group (lower part) in Sakawa area.

Neoschizodus (Neoschizodus) tokyoensis (Ichikawa)
1954a. Myophoria tokyoensis Ichikawa, p. 58, pl. 7, fig. 6.
Type. —Holotype (UMUT MM5431) from Arai, Itsukaichi, Tokyo Pref.
Age and distribution. —Triassic (precisely unknown). Arai formation in Itsukaichi area.

Neoschizodus (Neoschizodus) usugataniensis Ichikawa
1950. Myophoriopsis (Pseudocorbula?) orbicularis Ichikawa, p. 249, pl. 5, figs. 10, 11 (non Neoschizodus orbicularis (Bronn, 1837)).-1954d. Neoschizodus usugataniensis Ichikawa, p. 60.
Type. —Holotype (UMUT MM5183) from Usugatani, Kaminaka, Tokushima Pref.
Age and distribution. —Carnian. Kochigatani group (lower part) in Sakuradani area.

Neoschizodus (Neoschizodus) semicostatus Nakazawa
1955. Neoschizodus semicostatus Nakazawa, p. 252, pl. 15, figs. 1-5.
Type. —Holotype (UK JM10289) from Nishimitsumatsu, Takabama, Fukui Pref.
Age and distribution. —Carnian (or Norian). Nabae group (N4 formation) in Maizuru zone.

Neoschizodus (Okunominetania) okunominetaniensis (Ichikawa)
1949b. Myophoria okunominetaniensis Ichikawa, in Kobayashi and Ichikawa, p. 181, pl. 6, figs. 7-9.-1954d. Neoschizodus (Okunominetania) okunominetaniensis (Ichikawa): Ichikawa, p. 62, pl. 4, figs. 1-3.
Type. —Holotype (UMUT MM5231) from Okunominetani, Sakawa, Kochi Pref.
Age and distribution. —Carnian. Kochigatani group (lower part) in Sakawa and Sakuradani areas.

Neoschizodus (Okunominetania) kawarensis Nakazawa
1956. Neoschizodus (Okunominetania) kawarensis Nakazawa, p. 245, pl. 4, figs. 11-15.
Type. —Holotype (UK JM10389) from Kongoin, Maizuru, Kyoto Pref.
Age and distribution. —Carnian. Nabae group (N2 formation) in Maizuru zone.

Neoschizodus ? shikii Nakazawa
1960. Neoschizodus (?) shikii Nakazawa, p. 59, pl, 6, figs, 34-38.
Type. —Holotype (UK JM10468) from Katsuradani, Hirobatake, Kyoto Pref.
Age and distribution. —Skytian. Yakuno group (Hirobatake formation) in Maizuru zone.

Trigonia senex Kobayashi and Mori
1954. Trigonia senex Kobayashi and Mori, p. 167, pl. 16, fig. 8.
Type. —Holotype by monotypy (UMUT MM4305) from Niranohama, Utatsu, Miyagi Pref.
Age and distribution. —Hettangian. Shizukawa group (Niranohama formation) in Shizukawa area.

Trigonia sumiyagura Kobayashi and Kaseno [Pl. 5, Figs. 1, 2]
1947. Trigonia sumiyagura Kobayashi and Kaseno, p. 42, pl. 10, figs. 1, 2.-1954. Trigonia sumiyagura Kobayashi and Kaseno: Kobayashi and Mori, p. 168, pl. 16, figs. 1-3.-1954. Trigonia sumiyagura Kobayashi and Kaseno, var.: Kobayashi and Mori, p. 170, pl. 16, figs. 4-7.-1959c. Trigonia sumiyagura Kobayashi and Kaseno: Hayami, p. 65, text-fig. 1, pl. 5, figs. 21, 22.-1961b. Trigonia sumiyagura Kobayashi and Kaseno: Nakano, p. 84, pl. 8, fig. 1.
Type. —Holotype (UMUT MM4301) from Kosaba, Karakuwa, Miyagi Pref.
Age and distribution. —Bajocian. Karakuwa group (Kosaba formation) in Karakuwa area, Hashiura group (Aratozaki formation) in Shizukawa area, and Ojika group (Kodaijima formation) in Ojika area.

Explanation of Plate 5 Fig. 1. Trigonia sumiyagura Kobayashi and Kaseno. Holotype (UMUT MM430) × rubber cast from left external mould, ×1 Loc. Kosaba, Karakuwa (Bajocian, Karakuwa group). Fig. 2. The same species. Rubber cast from left external mould (UMUT MM2962), ×1. Loc. Akaiwazaki, Shizukawa (Bajocian, Hashiura group). Fig. 3. Geratrigonia hosourensis (Yokoyama): type-species of genus Geratrigonia. Lectoype (UMUT MM7174), left valve of a bivalved specimen, ×1. Loc. Niranohama, Shizukawa (Hettangian, Shizukawa group). Fig. 4. Latitrigonia pyramidalis Kobayashi and Tamura: type-species of genus Latitrigonia. Holotype (UMUT MM4378), rubber cast from left external mould, ×1.5. Loc. Nodezawa, Soma (Bajocian, Soma group). Fig. 5. Ibotrigonia masatanii Kobayashi and Tamura: type-species of genus Ibotrigonia. Rubber cast from left external mould (UMUT MM4383), ×1.5. Loc. Sugaya, Soma (Bathonian ?, Soma group). Fig, 6. Minetrigonia hegiensis hegiensis (Saeki): nominal subspecies of the type-species of genus Minetrigonia. Holotype (UMUT MM5026), rubber cast from left external mould, ×1.5. Loc. Nukata, Yakuno (Carnian, Heki formation). Fig. 7. Frenguelliella (Kumatrigonia) tanonrensis Tamura: type-species of subgenus Kumatrigonia. Holotype (UMUT MM3080), right valve, ×1. Loc. Okiba, Tanoura (Carnian, Kochigatani group). Fig. 8. Vaugonia (Hijitrigonia) geniculata Kobayashi and Mori: type-species of subgenus Hijitrigonia. Paratype (UMUT MM4338), rubber cast from left external mould, ×1. Loc. Akaiwazaki, Shizukawa (Bajocian, Shizukawa group). Fig, 9. Myophorella (Promyophorella) sigmoidalis Kobayashi and Tamura: type-species of subgenus Promyophorella. Holotype (UMUT MM4350), rubber cast from right external mould, ×1. Loc. Akaiwazaki, Shizukawa (Bajocian, Hashiura group). Fig. 10. Nipponitrigonia kikuchiana (Yokoyama); type-species of genus Nipponitrigonia. Right valve (GK not registered), ×1. Loc. Koikorobe, Tanohata (Aptian, Miyako group). Fig. 11. Steinmanella (Yeharlla) ainuana (Yabe and Nagao). Left valve of a bivalved specimen (GK H6054), ×1. Loc. Katsurazawa-dam, Ikushumbetsu (Cenomanian, Middle Yezo group). Fig. 12. Steinmanella (Yeharelld) japonica (Yehara): type-species of subgenus Yeharella. Rubber cast from left external mould (UMUT MM4413), ×1. Loc. Aonami, Onsen (Campanian, Izumi group). Fig. 13. Steinmanella (Setotrigonid) shinoharai Kobayashi and Amano: type-species of subgenus Setotrigonia. Holotype (UMUT MM4424), rubber cast from right external mould, ×1. Loc. Tsubasayama, Hiketa (Campanian, Izumi group).

Frenguelliella (Kumatrigonia) tanourensis Tamura [Pl. 5, Fig. 7]
1959a. Frenguelliella (Kumatrigonia) tanourensis Tamura, p. 214, text-fig. 2, pl. 2, figs. 1-6.
Type. —Holotype (UMUT MM3080) from Okiba, Tanoura, Kumamoto Pref.
Age and distribution. —Carnian. Kochigatani group (lower part) in Tanoura area.

Geratrigonia hosourensis (Yokoyama) [Pl. 5, Fig. 3]
1904. Trigonia hosourensis Yokoyama, p. 11, pl. 1, fig. 3.-1954. Geratrigonia hosourensis (Yokoyama): Kobayashi and Mori, p. 171, pl. 15, figs. 1, 2.-1954. Geratrigonia hosourensis (Yokoyama) var. convexa Kobayashi, in Kobayashi and Mori, p. 172, pl. 16, fig. 9.-1959. Geratrigonia hosourensis convexa Kobayashi: Kobayashi, Mori and Tamura, p. 289.-1959a. Geratrigonia hosourensis (Yokoyama): Hayami, p. 72, pl. 7, figs. 6-8.-1963. Geratrigonia hosourensis (Yolcoyama): Nakano, p. 519, pl. 56, fig. 3.-1968. Geratrigonia hosourensis (Yokoyama): Hayami and Nakano, p. 201, fig. 3-11.
Type. —Yokoyama (1904) described this species on the basis of two specimens. One of the syntype specimens, which was illustrated by Yokoyama (1904, pl. 1, fig. 3) and regarded as holotype by Kobayashi and Mori (1954, p. 172), is designated here as the lectotype (UMUT MM7174). It was collected from Niranohama, Utatsu, Miyagi Pref. Holotype by monotypy of Geratrigonia hosourensis var. convexa (UMUT MM4314) from the same locality.
Age and distribution. —Hettangian. Shizukawa group (Niranohama formation) in Shizukawa, Hashiura and Mizunuma areas.

Geratrigonia lata Kobayashi
1954. Geratrigonia lata Kobayashi, in Kobayashi and Mori, p. 173, pl. 15, figs. 6, 7.
Type. —Holotype (IGPS not registered; plaster cast UMUT MM4315) from Niranoharoa, Utatsu, Miyagi Pref.
Age and distribution. —Hettangian. Shizukawa group (Niranohama formation) in Shizukawa area.
Remarks. —This is possibly conspecific with Geratrigonia hosourensis.

Geratrigonia kurumensis Kobayashi
1957a. Geratrigonia kurumensis Kobayashi, p. 44, pl. 1, fig. 19.
Type. —Holotype by monotypy (UMUT MM4388) from Otakidani, Omi (Agero), Niigata Pref.
Age and distribution. —Toarcian. Kuruma group (Otakidani formation) in Omi area.

Latitrigonia pyramidalis Kobayashi and Tamura [Pl. 5, Fig. 4]
1957. Latitrigonia pyramidalis Kobayashi and Tamura, p. 36, pl. 1, fig. 8.-1963. Latitrigonia pyramidalis Kobayashi and Tamura: Nakano, p. 520, pl. 56, fig, 4.
Type. —Holotype by monotypy (UMUT MM4378) from Nodezawa, Soma, Fukushima Pref.
Age and distribution. —Bajocian (or Bathonian), Soma group (Awazu formation) in Soma area.

Latitrigonia unicarinata Kobayashi and Tamura
1957. Latitrigonia unicarinata Kobayashi and Tamura, p. 37, pl. 1, fig. 9.
Type. —Holotype (UMUT MM4379) from Sugaya, Soma, Fukushima Pref.
Age and distribution. —Bathonian (or thereabout). Soma group (Yamagami formation) in Soma area.

Latitrigonia unituberculata Kobayashi and Tamura
1957. Latitrigonia unituberculata Kobayashi and Tamura, p. 37, pl. 1, fig. 10.
Type. —Holotype (UMUT MM4380) from Sugaya, Soma, Fukushima Pref.
Age and distribution. —Bathonian (or thereabout). Soma group (Yamagami formation) in Soma area.

Latitrigonia tetoriensis Kobayashi
1957a. Latitrigonia tetoriensis Kobayashi, p. 45, pl. 1, figs. 11-13.
Type. —Holotype (UMUT MM4389) from Umagatani (Yambara), Izumi, Fukui Pref.
Age and distribution. —Oxfordian. Tetori group (Yambarazaka formation) in Izumi area.

Latitrigonia orbicularis Kobayashi
1957a. Latitrigonia orbicularis Kobayashi, p. 45, pl. 1, figs. 14, 15.
Type. —Holotype (UMUT MM4392) from Umagatani, Izumi, Fukui Pref.
Age and distribution. —Oxfordian. Tetori group (Yambarazaka formation) in Izumi area.

Ibotrigonia masatanii Kobayashi and Tamura [Pl. 5, Fig. 5]
1957. Ibotrigonia masatanii Kobayashi and Tamura, p. 38, pl. 1, figs. 5, 6.-1957. Ibotrigonia masatanii Kobayashi and Tamura var.: Kobayashi and Tamura, p. 39, pl. 1, fig. 7.-1963. Ibotrigonia masatanii Kobayashi and Tamura: Nakano, p. 521, pl. 56, fig. 5.
Type. —Holotype (UMUT MM4381) from Sugaya, Soma, Fukushima Pref.
Age and distribution. —Bathonian (or thereabout). Soma group (Yamagami formation) in Soma area.

Nipponitrigonia sagawai sagawai (Yehara)
1927. Trigonia sagawai Yehara, p. 34, pl. 3, fig. 10.-1954. Nipponitrigonia sagawai (Yehara): Kobayashi, p. 77.-1957c. Nipponitrigonia sagawai (Yehara): Kobayashi, p.53, pl. 10, figs. 2-8 (non figs. 9-11).-1960d. Nipponitrigonia sagawai (Yehara): Tamura, p. 234.-1962. Nipponitrigonia sagawai (Yehara): Maeda, p. 503, pl. 1, figs. 1-15.
Type. —Holotype by monotypy (UK not registered) from Kambaradani, Sakawa, Kochi Pref.
Age and distribution. —Bajocian-Tithonian. Torinosu group in Sakawa area, and Soma group (Awazu, Yamagami and Nakanosawa formations) in Soma area.

Nipponitrigonia sagawai kobayashii Maeda
1957c. Nipponitrigonia sagawai (Yehara): Kobayashi, p. 53 (pars), pl. 10, figs. 9-11 (non figs. 2-8).-1962c. Nipponitrigonia kobayashii Maeda, p. 505, pl. 2, figs. 1-15, pl. 3, figs. 13-15.-1962c. Nipponitrigonia imamurai Maeda, p. 506, pl. 3, figs. 1-12.-1963. Nipponitrigonia kobayashii Maeda: Maeda and Kawabe, p. 57, pl. 1, figs. 2-8.
Type. —Holotype (CU R627501) from Kiritani, Yatsuo, Toyama Pref. Holotype of Nipponitrigonia imamurai (CU R627601) from the same locality.
Age and distribution. —Oxfordian. Tetori group (Kiritani formation) in Yatsuo area.

Nipponitrigonia furuliawensis Maeda
1962a. Nipponitrigonia furukawensis Maeda, p. 276, pl. 42, figs. 1-15.
Type. —Holotype (CU R6192101) from Sugizaki, Furukawa, Gifu Pref.
Age and distribution. —Oxfordian (or thereabout). Tetori group (Sugizaki sandstone) in Furukawa area.

Nipponitrigonia sakamotoensis (Yehara)
1921. Trigonia sakamotoensis Yehara, p. 10, pl. 5, fig. 4.-1921. Trigonia kikuchiana Yokoyama: Yehara, pl. 5, fig. 3.-1923b. Trigonia naumanni Yehara, p. 81, pl. 8, figs. 1-3, pl. 9, fig. 6.-1954. Nipponitrigonia sakamotoensis (Yehara): Kobayashi, p. 77.-1957c. Nipponitrigonia naumanni (Yehara): Kobayashi, p. 54, pl. 10, figs. 12, 13, pl. 11, figs. 1, 2, ? 3.-1957c. Nipponitrigonia sakamotoensis (Yehara): Kobayashi, p. 55, pl. 10, fig. 15, pl. 11, fig. 8.-1958. Nipponitrigonia naumanni (Yehara); Kobayashi and Nakano, P. 144.-1962c. Nipponitrigonia naumanni (Yehara): Maeda, p. 510, pl. 6, figs. 1-12, pl. 7, figs. 1-14.-1964. Nipponitrigonia naumanni (Yehara): Maeda and Kitamura, p. 54, pl. 2, figs. 1-11, pl. 3, figs. 1-14, pl. 4, figs. 1-15.-1967b. Nipponitrigonia naumanni (Yehara): Maeda and Kawabe, p. 91, pl. 1, fig. 4.
Type. —Holotype by monotypy (UK JM10153) from Sakamoto, Katsuura, Tokushima Pref. Syntype of Trigonia naumanni (UK JM10152) from Katsuura, Katsuura, Tokushima Pref., Todai, Miwa, Nagano Pref. and Ninomiya, Sakawa, Kochi Pref.
Age and distribution. —Neocomian-Albian. Hoji formation in Katsuuragawa area, Lower Monobegawa group in Sakawa and Monobegawa areas, Todai formation in Takato area, and Kikunotani formation in Kurosegawa area.

Nipponitrigonia sanchuensis Maeda
1962c. Nipponitrigonia sanchuensis Maeda, p. 509, pl. 5, figs. 1-18.
Type. —Holotype (CU R 627401) from Ishido, Ohinata, Nagano Pref.
Age and distribution. —Upper Neocomian-Aptian. Ishido formation in Sanchu area.
Remarks. —This is intimately related to, if not identical with, Nipponitrigonia plirata Kobayashi and Nakano, 1958.

Nipponitrigonia choshiensis Maeda
1962c. Nipponitrigonia choshiensis Maeda, p. 507, pl. 4, figs. 1-13.-1972. Nipponitrigonia choshiensis Maeda: Shikama and Suzuki, pl. 6, fig. 1.
Type. —Holotype (CU R627201) from Ashikajima, Choshi, Chiba Pref.
Age and distribution. —Aptian. Choshi formation in Choshi area.

Nipponitrigonia kikuchiana (Yokoyama) [Pl. 5, Fig. 10]
1891. Trigonia kikuchiana Yokoyama, p. 363, pl. 40, figs. 4-6.-1891. Trigonia rotundata Yokoyama, p. 365, pl. 40, figs. 7-9.-1915. Trigonia kikuchiana Yokoyama: Yehara, p. 44, pl. 2, figs. 1-9.-1923a. Trigonia kikuchiana Yokoyama: Yehara, p. 80, pl. 11, figs, 1, 2.-1923b. Trigonia kikuchiana Yokoyama: Yehara, p. 9, pl. 7, figs. 1, 2.-1927. Trigonia kikuchiana Yokoyama: Yabe, pl. 4, fig. 4.-1934. Trigonia kikuchiana Yokoyama: Nagao, p. 206. -1952. Nipponitrigonia kikuchiana (Yokoyama): Cox, p. 53, pi. 3, fig. 6.-1954.Nipponitrigonia kikuchiana (Yokoyama): Kobayashi, p. 76.-1954. Nipponitrigonia rotun data (Yokoyama): Kobayashi. p. 77.-1957c. Nipponitrigonia kikuchiana (Yokoyama): Kobayashi, p. 53.-1958. Nipponitrigonia kikuchiana (Yokoyama): Kobayashi and Nakano, p. 143,-1962c. Nipponitrigonia kikuchiana (Yokoyama): Maeda, p. 511, pl. 8, figs. 1-10, pl. 9, figs. 1-17.-1963. Nipponitrigonia kikuchiana (Yokoyama): Nakano, p. 524, pl. 56, fig. 9.-1968. Nipponitrigonia kikuchiana (Yokoyama): Hayami and Nakano, p. 200, fig. 2-2.
Type. —Syntype (repository unknown) from Tanno, Katsuura, Tokushiroa Pref., Soyama, Nangoku, and Yamanokami, Sakawa, Kochi Pref. Syntype of Trigonia rotundata (repository unknown) from Tanno, Katsuura, Tokushima Pref. and Ninomiya, Yamanokami and Sendachino, Sakawa, Kochi Pref.
Age and distribution. —Neocomian-Cenomanian. Hoji formation in Katsuuragawa area, Lower Monobegawa group in Sakawa and Monobegawa areas, Miyako group (Tano-hata and Hiraiga formations) in Tanohata and Omoto areas, Arita formation in Yuasa area, Hinagu and Yatsushiro formations in Sakamoto and Yatsushiro areas, Kikunotani formation in Kurosegawa area, and Gosyonoura group in Gosyonoura island.

Nipponitrigonia convexa Kobayashi
1957c. Nipponitrigonia convexa Kobayashi, p. 55, pl. 10, fig. 14, pl. 11, figs. 4-7.
Type. —Syntype (IGPS not registered, UMUT MM4443-4445, UK not registered) from Yamanokami, Sakawa, Kochi Pref., Sendatsuno, Ochi, Kochi Pref., Miyanohara, Ochi, Kochi Pref., and Gosyonoura, Kumamoto Pref.
Age and distribution. —Neocomian-Cenomanian. Lower and Upper Monobegawa groups in Sakawa area, and Gosyonoura group in Gosyonoura island.
Remarks. —This is a doubtful species, and the type locality is not yet decided. All the syntype specimens are secondarily deformed, and morphological difference from Nipponitrigonia kikuchiana is not necessarily clear.

Nipponitrigonia quadrata Kobayashi and Nakano
1958. Nipponitrigonia quadrata Kobayashi and Nakano, p. 144, pl. 11, fig. 3.
Type. —Holotype (GK not registered) from Shimofukami, Sakamoto, Kumamoto Pref.
Age and distribution. —Albian. Yatsushiro formation in Sakamoto area.

Nipponitrigonia plicata Kobayashi and Nakano
1958. Nipponitrigonia kikuchiana var. plicata Kobayashi and Nakano, p. 143, pl. 11, figs. 1,2.
Type. —Holotype (GK not registered) from the north of Shimofukami, Sakamoto, Ku mamoto Pref. Age and distribution. —Upper Neocomian-Albian. Yatsushiro formation in Yatsushiro area, Arita formation in Yuasa area.

Rutitrigonia yeharai Kobayashi
1923a. Trigonia neumayri Yehara, p. 82, pl. 9, figs. 1-3. (non Trigonia neumayri Choffat, 1885)-1954. Rutitrigonia yeharai Kobayashi, p. 77.-1957c. Rutitrigonia yeharai Ko bayashi: Kobayashi, p. 59, pl. 10, fig. 1.-1958. Rutitrigonia yeharai Kobayashi: Kobayashi and Nakano, p. 145, pl. 12, figs. 9, 10.
Type. —Syntype (UK not registered) from Yamanokami, Sakawa, Kochi Pref.
Age and distribution. —Neocomian. Lower Monobegawa group (Yamanokami sandstone) in Sakawa area.

Rutitrigonia sanchuensis (Nakano)
1957c. Psilotrigonia sanchuensis Nakano, p. 70, text-figs. 1-3.-1958. Rutitrigonia san chuensis (Nakano): Kobayashi and Nakano, p. 145, pl. 12, figs. 1-8.
Type. —Holotype (Yokohama Nat, Univ. not registered) from Ohinata, Nagano Pref.
Age and distribution. —Upper Neocomian-Albian. Ishido formation in Sanchu area, and Yatsushiro formation in Sakamoto area.

Minetrigonia hegiensis hegiensis (Saeki) [Pl. 5, Fig. 6]
1925. Trigonia hegiensis Saeki, p. 35, pl. 12, figs. 1-3.-1925. Trigonia yeharai Saeki, p. 36, pl. 12, figs. 4, 5.-1952a. Minetrigonia hegiensis (Saeki): Kobayashi and Ichikawa, p. 72, pl.3, figs. 4-11.-1955. Minetrigonia hegiensis (Saeki): Nakazawa, p. 253, pl. 15, figs. 6-10.
Type. —Holotype (UMUT MM5026) from the west of Nukata, Heki (Yakuno), Kyoto Pref. Holotype of Trigonia yeharai (UMUT MM5028) from the same locality.
Age and distribution. —Carnian. Heki formation and Nabae group (N1 and N2 forma tions) in Maizuru zone.

Minetrigonia hegiensis obsoleta Nakazawa
1956. Minetrigonia hegiensis obsoleta Nakazawa, p. 246, pl. 4, figs. 5-9.
Type. —Holotype (UK JM10408) from Higashiarata, Takahama, Fukui Pref.
Age and distribution. —Carnian. Nabae group (N2 formation) in Maizuru zone.

Minetrigonia katayamai (Kobayashi and Ichikawa)
1938. Trigonia (Minetrigonia) hegiensis Saeki: Kobayashi and Katayama, p. 188, text-figs. 1, 2.-1949b. Trigonia (Minetrigonia) katayamai Kobayashi and Ichikawa, p. 184. 1954d. Minetrigonia katayamai (Kobayashi and Ichikawa): Ichikawa, p. 63, pl. 4, figs. 9, 10.-1956. Minetrigonia katayamai Kobayashi and Ichikawa: Nakazawa, p. 246, pl. 4, fig. 4.-1957b. Minetrigonia katayamai Kobayashi and Ichikawa: Nakano, p. 65, pl, 9, figs. 5-7.-1960c. Minetrigonia katayamai Kobayashi and Ichikawa: Tokuyama, p. 212, pl. 13, figs. 1-5.-1968. Minetrigonia katayamai Kobayashi and Ichikawa: Hayami and Nakano, p. 201, fig. 3-18.
Type. —Syntype (UMUT MM4238, 4239) from Mugikawa, Mine, Yamaguchi Pref., syntype from Okunominetani, Kashiwai and Oowada-Horiake, Sakawa, Kochi Pref.
Age and distribution. —Carnian. Mine group (Hirabara formation) in Mine area, Kochi gatani group (lower part) in Sakawa and Sakuradani areas, Nabae group (N2 formation) in Maizuru zone, and Kyowa formation in Nariwa area.

Prosogyrotrigonia inouyei (Yehara) [Pl. 5, Fig. 7]
1921. Trigonia inouyei Yehara, p. 8, pl. 5, figs. 1, 2.-1954. Prosogyrotrigonia inouyei (Yehara): Kobayashi, p. 76.-1954. Prosogyrotrigonia inouyei (Yehara): Kobayashi and Mori, p. 157, pl. 15, figs. 3-5.-1959h. Prosogyrotrigonia inouyei (Yehara): Hayami, p. 70, pl. 7, figs. 12-14.-1968. Prosogyrotrigonia inouyei (Yehara): Hayami and Nakano, p. 201, fig. 3-20.
Type. —Syntype (UK JM10151) from Higashinagano, Toyoda, Yamaguchi Pref.
Age and distribution. —Sinemurian. Toyora group (Higashinagano formation) in Toyoda area.

Vaugonia (Vaugonia) niranohamensis Kobayashi and Mori
1955. Vaugonia niranohamensis Kobayashi and Mori, p. 80, pl. 3, figs. 1-6, pl. 4, fig. 1.
Type. —Holotype (UMUT MM4323) from Niranohama, Utatsu, Miyagi Pref.
Age and distribution. —Hettangian-Bajocian. Shizukawa group (Niranohama and Hosoura formations) and Hashiura group (Aratozaki formation) in Shizukawa and Hashiura areas.

Vaugonia (Vaugonia) namigashira Kobayashi and Mori
1904. Trigonia v-costata Lycett: Yokoyama, p. 8, pl. 2, figs. 2-4.-1955. Vaugonia yoko yamai Kobayashi and Mori, p. 81, pl. 3, figs. 7, 8.-1955. Vaugonia yokoyamai forma gracilis Kobayashi and Mori, p. 81, pl. 3, fig. 9.-1955. Vaugonia namigashira Kobayashi and Mori, p. 83, pl. 3, figs. 10, 11.
Type. —Holotype (UMUT MM4333) from Hoinyashiki (Hosoura), Shizukawa, Miyagi Pref. Syntype of Vaugonia yokoyamai (UMUT MM4324-MM4326) from Hoinyashiki (Hosoura), Shizukawa; Oiwazawa, Kitakami (Hashiura); and Tsukinoura, Ishinomaki, all in Miyagi Pref. Holotype by monotypy of Vaugonia yokoyamai forma gracilis (UMUT MM4327) from Hoinyashiki.
Age and distribution. —Hettangian-Bajocian. Shizukawa group (Niranohama formation) and Hashiura group (Aratozaki formation) in Shizukawa and Hashiura areas, and Ojika group (Tsukinoura formation) in Ojika area.
Remarks. —Vaugonia yokoyamai and Vaugonia namigashira were proposed by Koba yashi and Mori (1955) in the same publication. Here, synonymizing the two, the latter name is adopted. Kobayashi and Mori indicated one of the original specimens of V. yokoyamai as "Yokoyama's type", but this indication is not regarded here as holotype designation.

Vaugonia (Vaugonia) kodaijimensis Kobayashi and Mori
1955. Vaugonia kodaijimensis Kobayashi and Mori, p. 82, pl. 3, figs. 12-15.
Type. —Holotype (UMUT MM4329) from Kodaijima, Ishinomaki, Miyagi Pref.
Age and distribution. —Bajocian. Ojika group (Kodaijima formation) in Ojika area.

Vaugonia (Vaugonia) awazuensis Kobayashi
1957. Vaugonia awazuensis Kobayashi, in Kobayashi and Taumra, p. 39, pl. 1, fig. 4.
Type. —Holotype by monotypy (UMUT MM4384) from Ono, Soma, Fukushima Pref.
Age and distribution. —Bajocian (or thereabout). Soma group (Awazu formation) in Soma area.

Vaugonia (Vaugonia) yambarensis Kobayashi
1956a. Vaugonia yambarensis Kobayashi, p. 1, pl. 1, fig. 1.
Type. —Holotype by monotypy (UMUT MM4366) from Yambara, Izumi, Fukui Pref.
Age and distribution. —Upper Jurassic (not older than Oxfordian). Tetori group (Yam bara formation) in Izumi area.

Vaugonia (Vaugonia) fukuiensis Maeda
1962d. Vaugonia fukuiensis Maeda, p. 515, pl. 1, figs. 1-16, pl. 2, figs. 2-16.
Type. —Holotype (CU R627703) from Aradani, Nishidani, Fukui Pref.
Age and distribution. —Oxfordian. Tetori group (Yambarazaka formation) in Nishidani area.

Vaugonia (Vaugonia) ariminensis Maeda and Kawabe
1963. Vaugonia ariminensis Maeda and Kawabe, p. 57, pl. 1, fig. 1.
Type. —Holotype (CU R 1-14) from Inonedani, Oyama, Toyama Pref.
Age and distribution. —Oxfordian (or thereabout). Tetori group (Magawa formation) in Arimine area.

Vaugonia (Hijitrigonia) geniculata Kobayashi and Mori [Pl. 5, Fig. 8]
1955. Vaugonia (Hijitrigonia) geniculata Kobayashi and Mori, p. 84, pl. 4, figs. 4-9.
Type. —Holotype (UMUT MM4337) from Akaiwazaki (Hosoura), Shizukawa, Miyagi Pref. Age and distribution. —Bajocian. Hashiura group (Aratozaki formation) in Shizukawa area, and Karakuwa group (Kosaba formation) in Karakuwa area.

Vaugonia (Hijitrigonia) kojiwa Kobayashi and Mori
1955. Vaugonia (Hijitrigonia) kojiwa Kobayashi and Mori, p. 85, pl. 4, figs. 2, 3.
Type. —Holotype (UMUT MM4342) from Yokokurazawa, Kitakami (Hashiura), Miya gi Pref.
Age and distribution. —Hettangian. Shizukawa group (Niranohama formation) in Hashi ura area.

Orthotrigonia ? midareta Kobayashi and Mori
1955. Orthotrigonia midareta Kobayashi and Mori, p. 87, pl. 4, fig. 11.-1955. Ortho trigonia corrugata Kobayashi and Mori, p. 87, pl. 4, fig. 10.
Type. —Holotype (UMUT MM4344) from Niranohama, Utatsu, Miyagi Pref. Holo type of Orthotrigonia corrugata (UMUT MM4345) from the same locality.
Age and distribution. —Hettangian. Shizukawa group (Niranohama formation) in Shizu kawa area.

Myophorella (Myophorella) dekaiboda Kobayashi and Tamura
1955. Myophorella (Myophorella) dekaiboda Kobayashi and Tamura, p. 95, pl. 6, figs. 6-9.
Type. —Holotype (UMUT MM4346) from Minahara, Kashima, Fukushima Pref.
Age and distribution. —Kimmeridgian. Soma group (Nakanosawa formation) in Soma area.

Myophorella (Promyophorella) sigmoidalis Kobayashi and Tamura [Pl. 5, Fig. 9]
1955. Myophorella (Promyophorella) sigmoidalis Kobayashi and Tamura, p. 96, pl. 5, figs. 1-3.-1959c. Myophorella (Promyophorella) sigmoidalis Kobayashi and Tamura: Hay ami, p. 66, pl. 5, fig. 24.
Type. —Holotype (UMUT MM4350) from Akaiwazaki (Hosoura), Shizukawa, Miyagi Pref.
Age and distribution. —Bajocian. Hashiura group (Aratozaki formation) in Shizukawa area.

Myophorella (Promyophorella) sugayensis Kobayashi and Tamura
1955. Myophorella (Promyophorella) sugayensis Kobayashi and Tamura, p. 97, pl. 5, fig. 4.-1955. Myophorella (Promyophorella) sugayensis var. geniculata Kobayashi and Tamura, p. 97, pl. 5, fig. 5.-1959. Myophorella (Promyophorella) sugayensis geniculata Kobayashi and Tamura: Kobayashi, Mori and Tamura, p. 290.
Type. —Holotype (UMUT MM4353) from Sugaya, Soma, Fukushima Pref. Holotype by monotypy of Myophorella (Promyophorella) sugayensis var. geniculata (UMUT MM 4354) from the same locality.
Age and distribution. —Bathonian (or thereabout). Soma group (Yamagami formation) in Soma area.

Myophorella (Promyophorella) imamurai Kobayashi
1956a. Myophorella (Promyophorella) imamurai Kobayashi, p. 3, pl. 1, fig. 3.
Type. —Holotype by monotypy (UMUT MM4368) from Kiritani, Yatsuo, Toyama Pref.
Age and distribution. —Oxfordian. Tetori group (Kiritani formation) in Yatsuo area.

Myophorella (Promyophorella) hashimotoi Kobayashi
1956a. Myophorella (Promyophorella?) hashimotoi Kobayashi, p. 3, pl. 1, figs. 4-7.-1960d. Myophorella (Promyophorella?) hashimotoi Kobayashi: Tamura, p. 234.
Type. —Holotype (UMUT MM4369) from Kurisaka, Kaminaka, Tokushima Pref.
Age and distribution. —Kimmeridgian. Torinosu group (Kurisaka formation) in Sakura dani area.

Myophorella (Promyophorella) toyamensis Maeda and Kawabe
1966a. Myophorella (Promyophorella) toyamensis Maeda and Kawabe, p. 43, pl. 1, figs. 1-14.
Type. —Holotype (CU R H-la) from Higashisakamoridani, Oyama, Toyama Pref.
Age and distribution. —Oxfordian. Tetori group (Magawa formation) in Arimine area.

Myophorella (Promyophorella) magawensis Maeda and Kawabe
1966a. Myophorella (Promyophorella) magawensis Maeda and Kawabe, p. 47, pl. 1, figs. 15-19.-1966a. Myophorella (Promyophorella) tetoriensis Maeda and Kawabe, p. 48, pl. 1, figs. 20-22.
Type. —Holotype (CU R M-71) from Magawa, Oyama, Toyama Pref. Syntype of Myo phorella (Promyophorella) tetoriensis (CU R m-280a, m-280b) from the same locality.
Age and distribution. —Oxfordian. Tetori group (Arimine formation) in Arimine area.

Myophorella (Promyophorella) hidensis Maeda and Kawabe
1966a. Myophorella (Promyophorella) hidensis Maeda and Kawabe, p. 46, pl. 2, figs. 1-29.
Type. —Holotype (CU R m-269) from Magawa, Oyama, Toyama Pref.
Age and distribution. —Oxfordian. Tetori group (Arimine formation) in Arimine area.

Myophorella (Promyophorella) orientalis Kobayashi and Tamura
1955. Myophorella (Promyophorella) orientalis Kobayashi and Tamura, p. 98, pl. 5, fig. 6. 1957a. Myophorella (Promyophorella) orientalis Kobayashi and Tamura: Kobayashi, p. 46, pl. 1, figs. 16-18.-1957b. Myophorella (Promyophorella) orientalis Kobayashi and Tamura: Kobayashi, p. 360, pl. 3, fig. 8.-compare 1960. Myophorella (Promyophorella) cf. orientalis Kobayashi and Tamura: Hayami, Sugita and Nagumo, p. 94.-1966b. Myophorella (Promyophorella) orientalis Kobayashi and Tamura: Maeda and Kawabe, p. 51, text-fig. 4, pl. 1, figs. 1-22, pl. 2, figs. 1-14.
Type. —Holotype (UMUT MM4355) from Umazawa (Koyamada), Kashima, Fuku shima Pref.
Age and distribution. —Callovian-Berriasian. Soma group (Koyamada formation) in Soma area, Ojika group (Tashiro sandstone) in Ojika area, Shishiori group (Kogoshio formation) in Kesennuma area, and Tetori group (Kaizara formation) in Izumi area. This species was also reported from Mindoro.

Myophorella (Promyophorella) obsoleta Kobayashi and Tamura
1955. Myophorella (Promyophorella) obsoleta Kobayashi and Tamura, p. 99, pl. 5, fig. 7.-1960. Myophorella (Promyophorella) obsoleta Kobayashi and Tamura: Hayami, Sugita and Nagumo, p. 94.
Type. —Holotype (UMUT MM4357) from Yobaiji-pass, Kesennuma, Miyagi Pref.
Age and distribution. —Tithonian-Berriasian. Shishiori group (Kogoshio formation) and Isokusa formation in Kesennuma and Oshima areas.

Myophorella (Haidaia) crenulata Kobayashi and Tamura
1955. Myophorella (Haidaia) crenulata Kobayashi and Tamura, p. 100, pl. 5, figs. 8-10.-1955. Myophorella (Haidaia) crenulata var. lunulata Kobayashi and Tamura, p. 101, pl. 6, figs. 1, 2.-1959. Myophorella (Haidaia) crenulata lunulata Kobayashi and Tamura: Kobayashi, Mori and Tamura, p. 290.-1961c. Myophorella (Haidaia) crenulata Kobayashi and Tamura: Hayami, p. 267, pl. 14, fig. 8.
Type. —Holotype (UMUT MM4358) from Minahara, Kashima, Fukushima Pref. Holo type of. Myophorella (Haidaia) crenulata var. lunulata (UMUT MM4361) from Minami sawa, Kashima, Fukushima Pref.
Age and distribution. —Kimmeridgian. Soma group (Nakanosawa formation) in Soma area, and Shishiori group (Mone formation) in Oshima area.

Myophorella (Haidaia) subcircularis Kobayashi and Tamura
1955. Myophorella (Haidaia) subcircularis Kobayashi and Tamura, p. 101, pl. 6, fig. 3.
Type. —Holotype (UMUT MM4363) from Nakanosawa, Kashima, Fukushima Pref.
Age and distribution. —Kimmeridgian. Soma group (Nakanosawa formation) in Soma area.

Myophorella (Haidaia) gracllenta Kobayashi
1956a. Myophorella (Haidaia) gracilenta Kobayashi, p. 4, pl. 1, fig. 8.-1959c. Myophorella (Haidaia) gracilenta Kobayashi: Tamura, p. 25, pl. 5, figs. 19-22.-1960d. Myophorella (Haidaia) gracilenta Kobayashi: Tamura, p. 234.
Type. —Holotype (UMUT MM4373) from Arinoki, Sakawa, Kochi Pref.
Age and distribution. —Upper Jurassic. Torinosu group in Sakawa and Sakamoto areas.

Myophorella (Haidaia) pulex Tamura
1959c. Myophorella (Haidaia) pulex Tamura, p. 25, text-fig. 2, pl. 5, figs. 15-18.-1960d. Myophorella (Haidaia) pulex Tamura, p. 234.
Type. —Holotype (UMUT MM2988) from Sakamoto, Sakamoto, Kumamoto Pref.
Age and distribution. —Upper Jurassic. Torinosu group in Sakamoto, Tanoura, Sakawa and Sakuradani areas.

Myophorella (Haidaia) ohmachii Tamura
1959c. Myophorella (Haidaia) ohmachii Tamura, p. 26, pl. 5, figs. 23-26.
Type. —Holotype (UMUT MM2998) from Uminoura, Tanoura, Kumamoto Pref.
Age and distribution. —Upper Jurassic. Torinosu group in Tanoura area.

Myophorella (Haidaia) kappazakensis Maeda and Adachi
1965. Myophorella (Haidaia) kappazakensis Maeda and Adachi, p. 322, text-fig. 3, pl. 1, figs. 1-5.
Type. —Holotype (CU R64100402) from Hirose, Minamimaki, Nagano Pref.
Age and distribution. —Upper Jurassic (precisely unknown). Torinosu group (Kappazaka formation) in Minamimaki area.

Linotrigonia (Linotrigonia) toyamai (Yehara)
1923b. Trigonia toyamai Yehara, p. 78, pl. 9, figs. 4, 5.-1927. Trigonia toyamai Yehara: Yehara, p. 35, pl. 3, fig. 9.-1954. Linotrigonia toyamai (Yehara): Kobayashi, p. 77.-1956a. Linotrigonia toyamai (Yehara): Kobayashi, p. 6, pl. 1, figs. 10-12.-1960d. Lino trigonia toyamai (Yehara): Tamura, p. 234.
Type. —Syntype (UK? not registered) from Nioigataki, Yoshidayashiki and Torinosu, Sakawa, and Ogawa, Monobegawa, all in Kochi Pref.
Age and distribution. —Upper Jurassic. Torinosu group in Sakawa, Monobegawa and Sakuradani areas.

Linotrigonia (Oistotrigonia ?) prima (Kobayashi and Tamura)
1955. Oistotrigonia prima Kobayashi and Tamura, p. 102, pl. 6, figs. 4, 5.
Type. —Holotype (UMUT MM4364) from Yamashita, Kashima, Fukushima Pref.
Age and distribution. —Kimmeridgian. Soma group (Nakanosawa formation) in Soma area.

Scaphotrigonia somensis Kobayashi and Tamura
1957. Scaphotrigonia somensis Kobayashi and Tamura, p. 40, pl. 1, figs. 1-3.
Type. —Holotype (UMUT MM4385) from Minahara, Soma, Fukushima Pref.
Age and distribution. —Bathonian (or thereabout). Soma group (Yamagami formation) in Soma area.

Steinmanella (Yeharella) japonica (Yehara) [Pl. 5, Fig. 12]
1923a. Trigonia japonica Yehara, p. 10, pl. 6, figs. 6, 7.-1923b, Trigonia japonica Yehara: Yehara, p. 83, pl. 12, figs. 3, 4.-1954. Steinmamella japonica (Yehara) [sic]: Kobayashi, p. 76.-1955. Steinmamella (Yeharella) japonica (Yehara) [sic]: Kobayashi and Amano, p. 201, pl. 14, figs. 1-3, pl. 15, fig. 4.-1955. Steinmannella (Yeharella) japonica var. obsoleta Kobayashi and Amano [sic], p. 202, pl. 14, figs. 4, 5.
Type. —Lectotype designated by Kobayashi and Amano (1955, p. 201) (UK JM10161) from Oe, Amakusa, Kumamoto Pref. Syntype of Steinmanella (Yeharella) japonica var. obsoleta (UMUT MM4417) from Imuta, Shimokoshiki, and syntype of the same variety (UMUT MM4418) from Tairajima, Shimokoshiki, both in Kagoshima Pref.
Age and distribution. —Campanian. Himenoura group in Amakusa and Shifliokoshiki islands, and Izumi group in Kitadani and Onsen areas.

Steinmanella (Yeharella) lymani Kobayashi and Amano
1915. Trigonia. cf. tryoniana Gabb: Yehara, p. 43, pl. 2, figs. 11-13.-1955. Steinmannella (Yeharella) lymani Kobayashi and Amano [sic], p. 203, pl. 13, fig. 3.
Type. —Holotype by monotypy (UMUT MM4419) from a boulder on a branch of Hoe river, south Saghalin.
Age and distribution. —Cenomanian-Turonian. Middle Yezo group in Ikushumbetsu, Yubari and Hoe river areas.

Steinmanella (Yeharella) kimurai kimurai (Tokunaga and Shimizu)
1926. Trigonia kimurai Tokunaga and Shimizu, p. 189, pl. 27, figs. 3, 4.-1954. Steinman nella kimurai (Tokunaga and Shimizu) [sic]: Kobayashi, p. 76.-1955, Steinmannella (Yeharella) kimurai (Tokunaga and Shimizu) [sic]: Kobayashi and Amano, p. 205, pl. 13, fig. 1 (non fig. 2)-1958. Steinmannella (Yeharella) kimurai (Tokunaga and Shimizu) [sic]: Nakano, p. 86.-1964. Steinmannella (Yeharella) kimurai (Tokunaga. and Shimizu) [sic]: Maeda and Sato, p. 64, text-fig. 8, pl. 1, figs. 1-6, pl. 2, figs. 1-5.
Type. —Syntype (lost by fire during the 2nd World War) from Sakakurazawa, Hirono, Fukushima Pref.
Age and distribution. —Coniacian. Futaba group in Futaba area.

Steinmanella (Yeharella) kimurai sanukiensis Nakano
1955. Steinmannella (Yeharella) kimurai (Tokunaga and Shimizu) [sic]: Kobayashi and Amano, p. 205, pl. 13, fig. 2 (non fig. 1).-1958. Steinmannella (Yeharella) kimurai (Toku naga and Shimizu) subspecies sanukiensis Nakano [sic], p. 86, pl. 13, fig. 1.
Type. —Holotype (IGSH NM. S. Y. 00001) from Kamikashiwara, Sogisho, Kagawa Pref.
Age and distribution. —Campanian. Izumi group (Korobishi formation) in Ayauta area.

Steinmanella (Yeharella) ainuana (Yabe and Nagao) [Pl. 5, Fig. 11]
1928. Trigonia ainuana Yabe and Nagao, p. 84, pl. 16, fig. 20.-1954. Steinmannella ainuana (Yabe and Nagao) [sic]: Kobayashi, p. 76.-1955. Steinmannella (Yeharella) ainuana (Yabe and Nagao) [sic]: Kobayashi and Amano, p. 204.-1961c. Steinmannella (Yeharella) ainuana (Yabe and Nagao) [sic]: Nakano, p. 141, pl. 20, figs. 1-6, pl. 21, figs. 1-6.-1968. Steinmannella (Yeharella) ainuana (Yabe and Nagao) [sic]: Hayami and Nakano, p. 200, fig. 2-4.
Type. —Holotype by monotypy (IGPS no, 22591) from Pombetsu, Mikasa (Ikushum betsu), Ishikari Prov., Hokkaido.
Age and distribution. —Cenomanian-Turonian. Middle Yezo group (Mikasa sandstone) in Ikushumbetsu area.

Steinmanella (Yeharella) deckeina (Kubota)
1952. Trigonia deckeina Kubota, p. 14, pl. 1, figs. 1, 2.-1958. Steinmannella (Yeharella) deckeina (Kubota) [sic]: Nakano, p. 87, pl. 13, fig. 2, pl. 14, fig. 1.
Type. —Holotype (GMH? not registered) from the upper course of Rupeshupe river (a tributary of the Teshio), Nakagawa, Teshio Prov., Hokkaido.
Age and distribution. —Campanian or Maestrichtian. Hakobuchi group in Abeshinai area.

Steinmanella (Yeharella) jimboi Kobayashi and Amano
1955. Steimnannella (Yeharella) jimboi Kobayashi and Amano [sic], p. 204, pl. 13, fig. 4.
Type. —Holotype by monotypy (UMUT MM4420) from Pombetsu, Mikasa (Ikushum betsu), Ishikari Prov., Hokkaido (not Yubari as originally described).
Age and distribution. —Cenomanian-Turonian. Middle Yezo group (Mikasa sandstone) in Ikushumbetsu area.

Steinmanella (Setotrigonia) shinoharai Kobayashi and Amano [Pl. 5, Fig. 13]
1955. Steinmannella (Setotrigonia) shinoharai Kobayashi and Amano [sic], p. 207, pl. 15, figs. 1-3.
Type. —Holotype (UMUT MM4424) from Tsubasayama, Hiketa, Kagawa Pref.
Age and distribution. —Campanian. Izumi group (basal part) in Hiketa area.

Apiotrigonia (Apiotrigonia) minor (Yabe and Nagao)
1915. Trigonia cf. subovalis Jimbo: Yehara, p. 42, pl. 1, figs. 14-17.-1921. Trigonia cf. subovalis Jimbo: Hayasaka, p. 4, pl. 1, fig. 2.-1923a. Trigonia cf. subovalis Jimbo: Yehara, p. 8, pl. 6, figs. 1-5.-1923b. Trigonia subovalis Jimbo: Yehara, p. 78, pl. 11, figs. 4-8. -1925. Trigonia subovalis var. minor Yabe and Nagao, p. 116.-1927, Trigonia subovalis var. minor Yabe and Nagao: Yabe, pl. 7, fig. 4.-compare 1930. Trigonia subovalis var. minor Yabe and Nagao: Nagao, p. 18.-1938. Trigonia subovalis var. minor Yabe and Nagao: Nagao and Otatume, p. 42, pl. 1, figs. 7-9.-1954. Apiotrigonia subovalis minor (Yabe and Nagao): Kobayashi, p. 77.-compare 1957a. "Trigonia subovalis Jimbo var. minor Yabe and Nagao": Amano, p. 57, pl. 1, fig. 19.-1957a. Apiotrigonia minor (Yabe and Nagao): Nakano, p. 110, pl. 8, figs. 1-4.-1962. Apiotrigonia minor (Yabe and Nagao): Saito, p. 63, pl. 1, figs. 8, 9.-1962. Apiotrigonia ashizawensis Saito, p. 64, pl. 1, fig. 6.-1967a. Apiotrigonia minor (Yabe and Nagao): Maeda and Kawabe, p. 423, pl. 1, figs. 10-25.-1967a. Apiotrigonia futabaensis Maeda and Kawabe, p. 421, pl. 1, figs. 5, 6.-1967a. Apiotrigonia hironoensis Maeda and Kawabe, p. 422, pl. 1, figs. 7-9.-1967a. Apiotrigonia orikiewsis Maeda and Kawabe, p, 423, pl. 1, figs. 1-4.
Type. —Holotype (IGPS ? not registered) from the south of Cape Khoi near Alexandrofsk, north Saghalin. Syntype of Apiotrigonia ashizawensis (GIUM nos. 40637-40639) from Ashizawa and a few other localities, Hisanohama and Hirono, Fukushima Pref. Holotype of Apiotrigonia futabaensis (CU R64031567) from Sakurazawa, holotype of Apiotrigonia hironoensis (CU R660219133) from Oriki, and holotype of Apiotrigonia orikiensis (CU R64031512) from Kitazawa; all in Hirono, Fukushima Pref.
Age and distribution. —Cenomanian-Campanian. Werblude group in Alexandrovsk area, Middle Yezo group (Mikasa sandstone) in Ikushumbetsu and Yubari areas, Futaba group (Ashizawa and Asamigawa formations) in Futaba area, Uwajima group in Uwajima area, Miyakura formation in Tokushima area, and (?) Himenoura group in Amakusa and Koshikijima islands.

Apiotrigonia (Apiotrigonia) undulosa Nakano
1957a. Apiotrigonia undulosa Nakano, p. 112, pl. 8, fig. 8.
Type. —Holotype (UMUT F-3a) from Taikorin, Hirono, Fukushima Pref.
Age and distribution. —Conlacian. Futaba group (lower part) in Futaba area, and Onogawa group (Inukai formation) in Onogawa area.

Apiotrigonia (Apiotrigonia) obliquecostata Nakano
1957a. Apiotrigonia obliquecostata Nakano, p. 113, pl. 8, figs. 9, 10.
Type. —Holotype (IGSH NM Am 1) from Wadanohana, Ryugatake (Amakusa-kami-shima), Kumamoto Pref.
Age and distribution. —Santonian. Himenoura group in Amakusa islands.

Apiotrigonia (Apiotrigonia) crassoradiata Nakano
1957a. Apiotrigonia crassoradiata Nakano, p. 113, pl, 8, figs. 11, 12.
Type. —Holotype (UMUT not registered) from Aonami, Yuyama, Ehime Pref.
Age and distribution. —Campanian. Izumi group (basal part) in Onsen area.

Apiotrigonia (Apiotrigonia) obsoleta Nakano
1957a. Apiotrigonia obsoleta Nakano, p. 114, pl. 9, figs. 5-7.-1957a. Apiotrigonia minor var. nankoi Nakano, p. 112, pl. 9, figs. 1-4.-1972. Apiotrigonia obsoleta Nakano: Tashiro, p. 331, pl. 41, figs. 1-8, 12, 13.
Type. —Holotype (IGSH NM Aw 1) from Hirota, Midori (Awaji), Hyogo Pref. Holo type of Apiotrigonia minor var. nankoi (IGSH NM Aw 7) from Hansanji, Seidan (Awaji), Hyogo Pref.
Age and distribution. —Campanian. Izumi group (Minato shale and Shichi shale) in Awaji island, and Himenoura group in Uto area.

Apiotrigonia (Apiotrigonia) postonodosa Nakano
1957a. Apiotrigonia postonodosa Nakano, p. 114, pl. 9, figs. 8-14.
Type. —Holotype (IGSH NM00004) from Noriden, Kawaura (Amakusa-shimoshima), Kumamoto Pref.
Age and distribution. —Campanian (or thereabout). Himenoura group (upper part) in Amakusa islands and Izumi group (Shichi shale) in Awaji island.

Apiotrigonia (Apiotrigonia) utoensis Tashiro
1972. Apiotrigonia utoensis Tashiro, p. 333, text-fig. 7, pl. 41, figs. 9-11.
Type. —Holotype (KE 1881) from Okoshiki, Uto, Kumamoto Pref.
Age and distribution. —Santonian or Campanian. Himenoura group (? upper part) in Uto area.

Apiotrigonia (Heterotrigonia) subovalis (Jimbo)
1894. Trigonia subovalis Jimbo, p. 42, pl. 8, fig. 5.-1923b. Trigonia sawatai Yehara, p. 80, pl. 10, fig. 9.-1954. Apiotrigonia subovalis (Jimbo): Kobayashi, p. 77.-1954. Hetero trigonia sawatai (Yehara): Kobayashi, p. 77.-1957a. Apiotrigonia jimboi Nakano, p. 115, pl. 8, figs. 5-7.-1957a. Heterotrigonia subovalis (Jimbo): Nakano, p. 118, pl. 8, figs. 13-15.-1961. Heterotrigonia subovalis (Jimbo): Nakano, p. 57, pl. 9, figs. 1-14.-1963. Heterotrigonia subovalis (Jimbo): Matsumoto, p. 45, pl. 67, fig. 5.
Type. —Lectotype designated by Matsumoto (1963, p. 45) (UMUT MM7488) from Pombetsu, Mikasa (Ikushumbetsu), Ishikari Prov. Hokkaido. Holotype by monotypy of Trigonia sawatai (UK? not registered) from Katsurazawa, Mikasa (Ikushumbetsu), Ishikari Prov., Hokkaido. Holotype of Apiotrigonia jimboi (UMUT Cr. 1284a) from Mikasa (Ikushumbetsu), Ishikari Prov., Hokkaido.
Age and distribution. —Cenomanian-Turonian. Middle Yezo group (Mikasa sandstone) in Ikushumbetsu area.

Apiotrigonia (Heterotrigonia) granosa (Nakano)
1957a. Heterotrigonia granosa Nakano, p. 119, pl. 8, fig. 16.
Type. —Holotype (IGSH NM Am 5) from Wadanohana, Ryugatake (Amakusa-kami-shima), Kumamoto Pref.
Age and distribution. —Santonian. Himenoura group (middle part) in Amakusa islands.

Apiotrigonia (Heterotrigonia) himenourensis (Tashiro)
1972. Heterotrigonia himenourensis Tashiro, p. 334, text-fig. 8, pl. 41, figs. 14-16.
Type. —Holotype (KE 1884) from Okoshiki, Uto, Kumamoto Pref.
Age and distribution. —Santonian or Campanian. Himenoura group in Amakusa and Shi mokoshiki islands.

Microtrigonia amanoi Nakano
1957a. Microtrigonia amanoi Nakano, p. 117, pl. 9, figs. 21, 22.
Type. —Holotype (KU MA00001) from Ukimizu, Kashima (Shimokoshiki), Kagoshima Pref.
Age and distribution. —Santonian or Campanian. Himenoura group (upper part) in Shi mokoshiki island.

Microtrigonia minima Nakano
1957a. Microtrigonia minima Nakano, p. 117, pl, 9, figs. 17-20.
Type. —Holotype (IGSH NM AW. Yt 1) from Mitsukawa, Sumoto (Awaji), Hyogo Pref.
Age and distribution. —Campanian-Maestrichtian. Izumi group (Shichi shale and Kitaama sandstone and shale) in Awaji island.

Microtrigonia tuberculata (Nakano)
1957a. Apiotrigonia tuberculata Nakano, p. 115, pl. 9, figs. 15, 16.
Type. —Holotype (IGSH NM00011) from Hansanji, Seidan (Awaji), Hyogo Pref.
Age and distribution. —Campanian. Izumi group (Shichi shale) in Awaji island.

Microtrigonia imutensis Tashiro
1972. Microtrigonia imutensis Tashiro, p. 335, text-fig. 9, pl. 40, fig. 26.
Type. —Holotype (KE1887) from Ukimizu, Kashima (Shimokoshiki), Kagoshima Pref.
Age and distribution. —Santonian or Campanian, Himenoura group (upper part) in Shi mokoshiki island.

Pterotrigonia (Pterotrigonia) pocilliformis (Yokoyama)
1891. Trigonia pocilliformis Yokoyama, p. 361, pl. 40, figs. 1-3.-1923b. Trigonia pocil liformis Yokoyama: Yehara, p. 71, pl. 9, figs. 8-10, pl. 10, figs. 4-6 (non pl. 10, figs. 1-3). -1926. Trigonia pocilliformis Yokoyama: Yabe, Nagao and Shimizu, p. 45.-1927. Trigonia pocilliformis Yokoyama: Yabe, pl. 4, fig. 3.-1954. Pterotrigonia pocilliformis (Yokoyama): Kobayashi, p. 77.-1957. Pterotrigonia pocilliformis (Yokoyama): Kobayashi and Nakano, p. 227, pl. 16, figs. 1-3.-1957. Pterotrigonia pocilliformis var. yamano kamiensis Kobayashi and Nakano, p. 229, pl. 16, figs. 8-10.-1958. Pterotrigonia pocil liformis (Yokoyama): Kobayashi and Nakano, p. 147, pl. 11, fig. 12.-1964. Pterotrigonia pocilliformis (Yokoyama): Matoba, pl. 37, figs. 6, 7.-1964. Pterotrigonia pocilliformis (Yokoyama): Maeda and Kitainura, p. 52, pl, 1, figs. 1-12.-1967b. Pterotrigonia pocil liformis (Yokoyama): Maeda and Kawabe, p. 91, pl. 1, figs. 1-3.
Type. —Syntype (repository unknown; plaster cast of one of the syntype specimens, UMUTMM4450) from Saoyama and Okuminodani, Nangoku; Hagino, Kahoku; Senda chino and Hirano, Ochi; Yamanokami, Sakawa, all in Kochi Pref.; and Tanno, Katsuura, Tokushima Pref. Holotype of Pterotrigonia pocilliformis var. yamanokamiensis (UMUT MM4453) from Yamanokami, Sakawa, Kochi Pref.
Age and distribution. —Neocomian-Albian. Lower Monobegawa group in Nangoku, Sakawa, Ochi and Monobegawa areas, Hoji and Hanoura formations in Katsuuragawa area, Arita formation in Yuasa area, Todai formation in Takato area, Ishido formation in Sanchu area, and Kikunotani formation in Kurosegawa area.

Pterotrigonia (Pterotrigonia) hokkaidoana (Yehara) [Pl, 6, Fig. 1]
1915. Trigonia hokkaidoana Yehara, p. 39, pl. 1, figs. 1-8.-1915. Trigonia kotoi Yehara, p. 40, pl. 1, fig. 10.-compare 1921. Trigonia cf. hokkaidoana Yehara: Hayasaka, p. 15, pl. 1, fig. 2-1923a. Trigonia hokkaidoana Yehara: Yehara, p. 5, pl. 7, figs. 3-5.-1923b. Trigonia hokkaidoana Yehara: Yehara, p. 70, pl. 11, figs. 9, 10, pl. 12, fig. 5.-1923b. Trigonia kotoi Yehara: Yehara, p. 73, pl. 9, fig. 7.-1925. Trigonia pocilliformis var. sachalinensis Yabe and Nagao, p. 118, pl. 28, figs. 5, 6.-1927. Trigonia hokkaidoana Yehara: Yabe, pl, 4, fig. 6.-1934. Trigonia hokkaidoana Yehara: Nagao, p. 205.-1934. Trigonia kotoi Yehara: Nagao, p. 206.-1954, Pterotrigonia hokkaidoana (Yehara): Kobayashi, p. 76.-1954. Pterotrigonia kotoi (Yehara): Kobayashi, p. 77.-1954. Ptero trigonia pocilliformis sachalinensis (Yabe and Nagao): Kobayashi, p. 77.-compare 1956a. Myophorella (Promyophorella) obsoleta Kobayashi and Tamura: Kobayashi, p. 2, pl. 1, fig. 2.-1957. Pterotrigonia hokkaidoana (Yehara): Kobayashi and Nakano, p. 229, pl. 16, fig. 4.-1958. Pterotrigonia hokkaidoana (Yehara): Kobayashi and Nakano, p. 148,pl, 11, figs. 9-11,-compare 1960d. Myophorella (Promyophorella) obsoleta Kobayashi and Tamura: Tamura, p. 234.-1964. Pterotrigonia hokkaidoana (Yehara): Matoba, p. 259, pl. 37, figs. 4, 5.-1964. Pterotrigonia cf. hokkaidoana (Yehara): Matoba, p. 259, pl. 37, figs. 1-3.-1967. Pterotrigonia (Pterotrigonia) hokkaidoana (Yehara): Hayami and Kawasawa, p. 79, pl. 9, figs. 6-9.-1968. Pterotrigonia hokkaidoana (Yehara): Hayami and Nakano, p. 200, fig. 2-6.-1969. Pterotrigonia hokkaidoana (Yehara): Hatai, Kotaka and Noda, p. 32, pl, 1, figs. 1,11.-1972. Pterotrigonia hokkaidoana (Yehara): Hashimoto, Hayaroi and Noda, p. 47, pl. 10, figs. 2-5.
Type. —Lectotype designated by Kobayashi and Nakano (1957, p. 230) (IGPS no. 4224) from Hiraiga, Tanohata, Iwate Pref. Holotype by monotypy of Trigonia kotoi (IGPS no. 4351) from the same locality. Syntype of Trigonia pocilliformis var. sachalinensis (IGPS not registered) from the south of Cape Khoi, near Alexandrovsk, north Saghalin.
Age and distribution. —Upper Neocomian-Cenomanian. Miyako group (Tanohata, Hiraiga and Aketo formations) in Tanohata and Miyako areas, Middle Yezo group (Mikasa sandstone) in Ikushumbetsu area, Ishido formation in Sanchu area, Arita formation in Yuasa area, Oshima formation in Oshima area, Hachiryusan, Hinagu and Yatsushiro formations in Sakamoto and Yatsushiro areas, Haidateyama formation in Nozu area, Lower Monobegawa group in Sakawa, Monobegawa and Ochi areas, Hoji formation in Katsuuragawa area, Gosyonoura group in Gosyonoura island, Shimantogawa group (Doganaro formation) in Susaki area, Gumizaki formation in Gumizaki area, and Miocene Misaki formation in Misaki area (derived fossil).
Remarks. —The relationship between Pterotrigonia (Pterotrigonia) pocilliformis and the present species should be further studied, because their discrimination is not necessarily clear.

Explanation of Plate 6 Fig. 1. Pterotrigonia (Pterotrigonia) hokkaidoana (Yehara). Left valve (GK not registered), × . Loc. Haipe, Tanohata (Aptian, Miyako group). Fig. 2. Sphaeriola nipponica Hayami. Holotype (UMUT MM3450), rubber cast from right internal mould, ×1. Loc. Higashinagano, Toyoda (Sinemurian, Toyora group). Fig. 3. Astarte (Astarte) subsenecta Yabe and Nagao. Rubber cast from left external mould (GK H6405), ×1.5. Loc. Ichinose-bashi, Nakazato (up. Neocomian or Aptian, Ishido formation). Fig. 4. The same species. Rubber cast from left internal mould (GK H6403), ×1.5. Loc. ditto. Fig. 5. Astarte (Yabed) shinanoensis Yabe and Nagao: type-species of subgenus Yabea. Rubber cast from internal (5a) and external (5b) moulds of a left valve (GK H6652), ×1.5. Loc. ditto. Fig. 6. Eriphyla (Eriphyla) miyakoensis Nagao. Topotype (GK H6433), right valve, ×1. Loc. Hiraiga, Tanohata (Aptian, Miyako group). Fig. 7. The same species. Topotype (GK H6436), right valve, ×1.5. Loc. ditto. Fig. 8. Anthonya subcantiana Nagao. Topotype (GK H6464), right valve, ×1.5. Loc, Haipe, Tanohata (Aptian, Miyako group). Fig. 9. The same species. Left valve (GK H6471), ×1.5. Loc. Hiraiga, Tanohata (Aptian, Miyako group). Fig. 10. Cardinia. toriyamai Hayami. Holotype (UMUT MM2918), plaster cast from left internal mould, ×1. Loc. Higashinagano, Toyoda (Sinemurian, Toyora group). Fig. 11. The same species. Paratype (UMUT MM2917), plaster cast from right external mould, ×1. Loc. ditto. Fig. 12. Minepharus triadicus (Tokuyama): type-species of genus Minepharus. Holotype (UMUT MM4470), left valve, ×1. Loc. Hirabarazaka, Mine (Carnian, Mine group). Fig. 13. The same species. Paratype (UMUT MM4475), rubber cast from left internal mould, ×1. Loc. ditto. Fig. 14. Globocardium sphaeroideum (Forbes): type-species of genus Globocardium. Left valve (GK not registered), ×1. Loc. Hiraiga, Tanohata (Aptian, Miyako group).

Pterotrigonia (Pterotrigonia) yokoyamai (Yehara)
1915. Trigonia yokoyamai Yehara, p. 41, pl, 2, figs. 15-17.-1934. Trigonia yokoyamai Yehara: Nagao, p. 205.-1954. Pterotrigonia yokoyamai (Yehara): Kobayashi, p. 77.
Type. —Syntype (IGPS nos. 4366, 4367) from Hiraiga, Tanohata, Iwate Pref.
Age and distribution. —Upper Neocomian (?)-Aptian. Miyako group (Hiraiga formation) in Tanohata area, and (?) Ishido formation in Sanchu area.

Pterotrigonia (Pterotrigonia) datemasamunei (Yehara)
1915. Trigonia datemasamunei Yehara, p. 38, pl. 2, figs. 13. 14.-1923b. Trigonia date masamunei var.: Yehara, p. 69, pl. 10, figs. 7, 8.-1934. Trigonia datemasamunei Yehara: Nagao, p. 205.-1954. Pterotrigonia datemasamunei (Yehara): Kobayashi, p. 76.-1958. Pteroirigonia datemasamunei (Yehara): Kobayashi and Nakano, p. 148, pl. 11, figs. 5, 6.
Type. —Syntype (IGPS no. 4331) from Raga, Tanohata, Miyagi Pref.
Age and distribution. —Aptian-Albian. Miyako group (Hiraiga formation) in Tanohata area, and Haidateyama formation in Nozu area.

Pterotrigonia (Pterotrigonia) brevicula (Yehara)
1915. Trigonia brevicula Yehara, p. 42, pl, 2, figs. 18, 19.-1954. Pterotrigonia brevicula (Yehara): Kobayashi, p. 76.-1961. Pterotrigonia brevicula (Yehara): Nakano and Numano, p. 91, pl. 13, figs, 4-8.
Type. —Lectotype designated by Nakano and Numano (1961, p. 91) (IGPS no. 4329) from Mikasa (Ikushumbetsu), Ishikari Prov., Hokkaido.
Age and distribution. —Cenomanian-Turonian. Middle yezo group (Mikasa sandstone) in Ikushumbetsu area.

Pterotrigonia (Pterotrigonia) sakakurai (Yehara)
1923a. Trigonia sakakurai Yehara, p. 6, pl. 4, fig. 6.-1923b. Trigonia sakakurai Yehara: Yehara, p. 76, pl. 11, fig. 3, pl. 13, fig. 2.-1954. Pterotrigonia sakakurai (Yehara): Kobayashi, p. 77.-1961. Pterotrigonia sakakurai (Yehara): Nakano and Numano, p. 93, pl. 13, figs. 9, 10.
Type. —Lectotype designated by Nakano and Numano (1961, p. 93) (UK JM10171) from Gosyonoura, Kumamoto Pref.
Age and distribution. —Albian (?)-Cenomanian. Gosyonoura group (mainly middle part) in Gosyonoura island.

Pterotrigonia (Acanthotrigonia) longiloba (Jimbo)
1894. Trigonia longiloba Jimbo, p. 38, pl. 8, figs. 2-4.-1915. Trigonia longiloba Jimbo: Yehara, p. 40, pl. 1, fig. 9, pl. 2, figs. 10-12.-1923b. Trigonia longiloba Jimbo: Yehara, p. 73, pl. 8, figs. 5-8.-1954. Pterotrigonia longiloba (Jimbo): Kobayashi, p. 77.-1957. Acanthotrigonia longiloba (Jimbo): Kobayashi and Nakano, p. 234, pl. 17, figs. 3-6.-1963. Acanthotrigonia longiloba (Jimbo): Matsumoto, p. 45, pl. 67, figs. 2-4.
Type. —Lectotype designated by Kobayashi and Nakano (1957, p. 235) (see also Matsumoto, 1963, p. 45) (UMUT MM7489) from Ponhorokabetsu, Yubari, Ishikari Prov., Hokkaido.
Age and distribution. —Cenomanian-Turonian. Middle Yezo group (Mikasa sandstone) in Yubari and Ikushumbetsu areas, and Miyanohara formation in Ochi area.

Pterotrigonia (Acanthotrigonia) moriana (Yehara)
1927. Trigonia moriana Yehara, p. 33, pl. 3, figs. 7, 8.-1954. Pterotrigonia moriana (Ye hara): Kobayashi, p. 77.-1957. Acanthotrigonia moriana (Yehara): Kobayashi and Nakano, p. 233, pl. 16, figs. 5, 6, pl. 17, figs. 9, 10.
Type. —Lectotype designated by Kobayashi and Nakano (1957, p. 233) (UK JM10172) from Hagino, Kahoku, Kochi Pref.
Age and distribution. —Aptian. Lower Monobegawa group (Hagino formation) in Monobegawa area.

Pterotrigonia (Acanthotrigonia) dilapsa (Yehara)
1923a. Trigonia dilapsa Yehara, p. 2, pl. 4, figs. 1, 2, pl. 5, fig. a.-1923b. Trigonia dilapsa Yehara: Yehara, p. 74, pl. 8, fig. 9, pl. 12, figs. 1, 2, pl. 13, fig. la.-1954. Pterotrigonia dilapsa (Yehara): Kobayashi, p. 76.
Type. —Syntype (UK JM10156) from Gosyonoura and Oe (Amakusa), Kumamoto Pref.
Age and distribution. —Albian (?)-Cenomanian. Gosyonoura group in Gosyonoura island.

Pterotrigonia (Acanthotrigonia) ogawai (Yehara)
1923a. Trigonia ogawai Yehara, p. 4, pl. 4, figs. 3-5.-1923b. Trigonia ogawai Yehara: Yehara, p. 75, pl. 12, figs, 6-8, pl. 13, fig. lb.-1954. Pterotrigonia ogawai (Yehara): Kobayashi, p. 77.-1957. Acanthotrigonia ogawai (Yehara): Kobayashi and Nakano, p. 235, pl. 17, figs. 1, 2.-1958. Acanthotrigonia ogawai (Yehara): Kobayashi and Nakano, p. 150, pl. 11, fig. 4.
Type. —Lectotype designated by Kobayashi and Nakano (1958, p. 150) (UK JM10195) from Gosyonoura, Kumamoto Pref.
Age and distribution. —Albian (?)-Cenomanian. Gosyonoura group in Gosyonoura is land, and Miyaji formation in Yatsushiro area.

Pterotrigonia (Acanthotrigonia) pustulosa (Nagao)
1923b. Trigonia pocilliformis Yokoyama: Yehara, p. 71 (pars), pl. 10, figs. 1-3 (non pl. 9, figs. 8-10, pl. 10, figs. 4-6).-1930. Trigonia pustulosa Nagao, p. 17, pl. 3, figs. 9-12-1954. Pterotrigoniapustulosa (Nagao): Kobayashi, p. 77.-1957. Acanthotrigonia pustulosa (Nagao): Kobayashi and Nakano, p. 234, pl. 16, fig. 7, pl. 17, figs. 7, 8.
Type. —Syntype (GMH? not registered) from Gosyonoura, Kumamoto Pref.
Age and distribution. —Albian (?)-Cenomanian. Gosyonoura group in Gosyonoura island, and Miyanohara formation in Ochi area.

Pterotrigonia (Acanthotrigonia) yeharai Nakano and Numano
1923a. Trigonia. yokoyamai var.: Yehara, p. 7, pl. 6, fig. 8.-1923b. Trigonia sakakurai var.: Yehara, p. 77, pl. 12, fig. 9.-1961. Pterotrigonia (Rinetrigonia) yeharai Nakano and Numano, p. 95, pl. 13, figs. 1, 2.-1968. Acanthotrigonia yeharai (Nakano and Numano): Tamura, Tashiro and Motojima, p. 38, text-fig. 2, pl. 1, figs. 19-23.
Type. —Holotype (IGSH NM3028a) from Enokuchi, Gosyonoura, Kumamoto Pref.
Age and distribution. —Albian (?)-Cenomanian. Gosyonoura group in Gosyonoura island.

Pterotrigonia (Acanthotrigonia) higoensis (Tamura and Tashiro)
1961. Pterotrigonia (Rinetrigonia) sp.: Nakano and Numano, p. 96, pl. 13, fig. 3.-1967. Acanthotrigonia higoensis Tamura and Tashiro, p. 17, text-fig. 2, pl. 1, figs. 14-17.
Type. —Holotype (KE 1725) from Kawauchi, Yabe, Kumamoto Pref.
Age and distribution. —Cenomanian-Turonian. Mifune group in Yabe and Matsubase areas.

Pterotrigonia (Acanthotrigonia) mashikensis (Tamura and Tashiro)
1967. Acanthotrigonia mashikensis Tamura and Tashiro, p. 19, text-fig, 2, pl. 1, figs. 1-7.
Type. —Holotype (KE 1712) from Itoishi, Toyono, Kumamoto Pref.
Age and distribution. —Cenomanian-Turonian. Mifune group in Matsubase, Yabe and Mifune areas.

Pterotrigonia (Acanthotrigonia) mifunensis (Tamura and Tashiro)
1967. Acanthotrigonia mifunensis Tamura and Tashiro, p. 20, text-fig. 2, pl. 1, figs. 8-13.
Type. —Holotype (KE 1719) from Itoishi, Toyono, Kumamoto Pref.
Age and distribution. —Cenomanian-Turonian. Mifune group in Matsubase area.
Remarks. —This is possibly conspecific with Pterotrigonia (Acanthotrigonia) mashikensis.

Pterotrigonia (Scabrotrigonia) imanishii (Nakano)
1956. Trigonia podlliformis Yokoyama: Imanishi, p. 53, figs. 1, 3.-1958b. Scabrotrigonia imanishii Nakano, p. 230, pl. 29, figs. 1-4.
Type. —Holotype (IGSH NM Sc-i 01) from Horombetsu, Utanobori, Kitami Prov., Hokkaido.
Age and distribution. —Aptian-Albian. Horombetsu formation in Esashi area.

Pterotrigonia (Scabrotrigonia) obsoleta (Nakano)
1958b. Scabrotrigonia obsoleta Nakano, p. 230, pl. 29, fig. 5.
Type. —Holotype (IGSH NM Sc-o 01) from Kurosaki, Gosyonoura, Kumamoto Pref.
Age and distribution. —Albian (?)-Cenomanian. Gosyonoura group (middle part) in Go syonoura island.

Pterotrigonia (Scabrotrigonia) kobayashii (Nakano)
1958b. Scabrotrigonia kobayashii Nakano, p. 231, pl. 29, figs. 6, 7.
Type. —Holotype (IGSH NM Sc-k 01) from Katsurazawa, Ikushumbetsu, Ishikari Prov., Hokkaido.
Age and distribution. —Cenomanian-Turonian. Middle Yezo group (Mikasa sandstone) in Ikushumbetsu area.