河南鲤科鱼类咽骨咽齿的比较研究(二)

<正> 本文记述了密鲴亚科鱼类4属4种,鲤卿亚科鱼类2属2种,现分述如下:I密鲴亚科:咽骨较宽,前后角明显。骨长为骨宽的2.5～4.4倍。体长为骨长的14.3～17.0倍。前肢稍长于后肢。前无齿突顶端尖;后无齿突侧扁,顶端园钝。咽齿1～3列,侧扁,先端尖不带钩,内列齿6～7枚,咀嚼面发达。咽齿1列以上者,外列齿细长而弱,容易

THE COMPARATIVE STUDIES OE THE PHARYNGEAL BONES AND THEIR TEETH OF CYPRINIDAE IN HENAN (2)

This paper reports the morphology of the pharyngeal bones and their teeth in 4 genera and 4 species of Xenocyprinae, in 2 genera and 2 species of Cyrininae. 1、In Xenocyprinae: Pharyngeals are rather short and broad with both the anterior and postcrior angles well deveoped. Length 14.3~17.0 times in stand- ard body length, width 2.5~4.4 in legth. The anterior limb is longer than posterior limb. Tip of anter or edentulous pro- ocess pointed, posterior edentulous stouded in terminal. Teeth 1 to 3 rows, hight compressed pointed in tip and hookness (not curve) ,The first row 6~7 teeth, grinding surface is rounded at the base and tapers to a point at the tip. If the teeth are more than in one row, those in the second or the third row are particularly small and slender. Key to species A. Teeth 3 rows B. Width 7.4~8.9 in head lenghh, the posterior edentulous shorter than the anterior or cqual, rounded in terminal…… ……Plagiognathops microlepis (Blcekcr) BB. Width 8.5~9.3 in head length, the posterior edentulous shorter than the anterior, stoubed in terminal…… ……Xenocypris argentea Gunther AA. Teeth 2 rows, the first row are large in size and form. The anterior and posterior angle are very distnct but not produced or slightly produced……Distoechodon tumirostris Peters AAA. Teeth 1 row,the first teeth. of the first row is par- ticularly small. The anterior angle is greatly produced but post- erior angle is obtuse……Aeanthobrama simoni Bleeker 2, In Cyprininae: Pharyngeal bones rather short and broad, length 8.3~13.0 times in standar body length, width 2.5~4.0 times in length, anterior limb longer than the posterior, with distinct anterior angle and indistinct posterior. Tip of anterior edentulous process pointed, posterior edentulous process depressed and twisted in terminal region. Teeth 3 rows in Cyprinus and I row in Carassius. Symmetical in number in both sidcs, with strong grinding surface in the teeth of the first row. Key to species A. Teeth 1 row, O. 0.4~4.0. O, width over 3 times in length ……Carassius auratus (L.) AA Teeth 3 rows. 1. 1.3~3.1.1, width below 3 times in length……Cyprinus carpio L.