Early Cretaceous Freshwater Fish Fauna in Kyushu, Japan

More documents

Recommendations

Info

182 Yoshitaka Yabumoto Horizon. The horizon at Kumagai is the Fourth Formation (the uppermost forma tion, W4, correlated to the Upper Wakamiya Formation) and the horizon of Minami gaoka is the Third Formation (the upper formation, W3, correlated to the Lower Wakamiya Formation) of the Wakino Subgroup in the Kwanmon Group, the Lower Cretaceous. Etymology. The species is named for Mr. Tateyu Aoki, who collected and donated the specimens to the Kitakyushu Museum and Institute of Natural History. Description of the holotype. The body is slender and the body depth is contained 6.4 times in the standard length. The head length is contained 4.4 times in the standard length. The median fins are relatively posterior in position. The dorsal origin is behind the anal origin and about vertical with the anterior one fourth of the anal base. The first dorsal fin pterygiophore is inserted between the fourth and fifth caudal vertebrae. The dorsal fin base is about half of the anal fin base. The pectoral fin elongates and extends over the middle of the abdomen. The pelvic fin is not preserved on the holotype. The caudal fin is forked. The number of principal dorsal fin rays is 11. There are 12dorsal fin pterygiophores and a stay. The number of principal anal fin rays is 22. There are 21 anal fin pterygiophores. The principal dorsal and anal fin rays are preceded by three small unbranched accessory rays respectively. Twelve pectoral fin rays are visible. The total number of vertebrae is 48, with 23 caudal vertebrae. The anterior end of the vertebral column is not visible. The number of abdominal vertebrae was estimated on the basis of the ribs. The number of ribs is 23. There is a seriesof median supraneurals beginning immediately behind the head and ending above the first caudal vertebra. Each supraneural of the anterior two-thirds is wide and leaf-shape with a ridge running from a dorso-posterior corner to an anteroventral corner (Fig. 52). The gape of the mouth is large. The lower jaw is long. The dentary bears small canine like teeth on its oral margin. The suture between the dentary and anglo-articular is not visible and the posterior part of the lower jaw is poorly preserved. The mandibular sensory canal runs within thedentary. The premaxilla has canine like teeth which are larger than those of the dentary. The posterior end of the lowerjaw is placed below the center of the orbit. The maxilla is not visible. There are villiform teeth on the endopterygoid. Teeth are not visible on the parasphenoid. The frontal is long and carries a superficial long groove (Fig. 54). The first preural centrum bears the narrow parhypural. The neural arch and spine of the first preural centrum are complete. There are seven hypurals. The first hypural is the largest. The second hypural is about halfof thewidth ofthe first one in width. There is a space between the second and the third hypurals. The
10mm Fig. 52. Wakinoichthys aokii gen. et. sp. nov., the holotype, KMNH VP100.140, from the Fourth Formation. o
Page 1 and 2:
Bull. Kitakyushu Mus. Nat. Hist., 1
Page 3 and 4:
Early Cretaceous Freshwater Fish Fa
Page 5 and 6:
Page 9 and 10:
Page 11 and 12:
Page 13 and 14:
Page 15 and 16:
Page 17 and 18:
Page 19 and 20:
Page 21 and 22:
Fig. 10. Nipponamia satoi gen. et s
Page 23 and 24:
Early Cretaceous Freshwater Fisli F
Page 25 and 26:
Page 27 and 28: Early Cretaceous Freshwater Fish Fa
Page 29 and 30: Fig. 19. Chuhsiungichthys yanagidai
Page 33 and 34: 40-42 2.9 Early Cretaceous Freshwat
Page 41 and 42: EarlyCretaceous Freshwater Fish Fau
Page 53 and 54: Fig. 37. Aokiichthys changae gen. e
Page 77: Early Cretaceous Freshwater Fish Fa
Page 89 and 90: Fig. 61. Wakinoichthys robustus gen
Page 113 and 114: Fig. 79. Diplomystus sp., restorati
Page 129 and 130:
Page 131 and 132:
EarlyCretaceous Freshwater Fish Fau
Page 133 and 134:
Page 135 and 136:
Page 137 and 138:
Page 139 and 140:
Page 142 and 143:
Page 144 and 145:
Page 146 and 147:
Page 148 and 149:
Page 150 and 151:
Page 152 and 153:
Page 154 and 155:
Yabumoto, Y. Early Cretaceous Fresh
Page 156 and 157:
• Yabumoto, Y. Early Cretaceous F
Page 158 and 159:
J. Yabumoto, Y. Early Cretaceous Fr
Page 160 and 161:
Page 162 and 163:
Page 164 and 165:
Page 166 and 167:
Page 168 and 169:
Page 170 and 171:
Page 172 and 173:
Page 174 and 175:
Page 176 and 177:
Page 178 and 179:
Page 180 and 181:
Page 182 and 183:
Page 184 and 185:
Page 186 and 187:
Page 188 and 189:
Page 190 and 191:
Page 192 and 193:
Page 194 and 195:
Page 196 and 197:
Page 198 and 199:
Page 200:
show all

Early Cretaceous Freshwater Fish Fauna in Kyushu, Japan

Create successful ePaper yourself

Delete template?

Save as template?