41 



autapomorphy. The apomorphies, the number of species, and the geographic distribution 

 of each genus are briefly discussed under the related node. 



Node A: This node unites all eight genera of the Hemitremian clade as a monophyletic 

 group. All genera of the clade share the anteriorly positioned anterior anal pterygiopho- 

 res. 



Hemitremia Cope. 1870 is the sistergroup of the other seven genera of Hemitremians. Five 

 apomorphies are present in the genus Hemitremia: (15*) anterolateral margin of frontal 

 bearing a deep notch; (16) anterior margin of orbital septum forming an anteriorly direc- 

 ted sharp process; (19) a cartilage present infront of the orbital septum in adult; (28*) 

 ventral portion of the posttemporal bone expanded; and (29*) middle portion of the su- 

 pracleithrum expanded. 



One species, Hemitremia flammea (Jordan & Gilbert), is in the genus which occurs in the 

 tributaries of the middle Cumberland, upper Duke, and middle Tennessee River in Tenn- 

 essee, Alabama, and Georgia (Böschung 1980). 



Node B: This node unites the other seven genera of Hemitremians as a monophyletic 

 group. Two synapomorphies are shared by these seven genera: (20) the supraorbital bone 

 small (reversed in Lagowskiella and Couesius), and (22*) the parasphenoid relatively bent. 

 Node C: Four Eurasian genera, Eupallasella, Rhynchocypris, Lagowskiella, and Phoxi- 

 nus, are united by node C. They share two synapomorphies: (8*) scale bearing both api- 

 cal and basal radii; (9*) scale on caudal peduncle elongated. 



These four genera were previously considered one genus, Phoxinus (e.g.. Berg 1949). Ho- 

 wes (1985) separated Rhynchocypris, Lagowskiella, and Eupallasella from Phoxinus, and 

 gave all of them generic status. 



Eight synapomorphies are shared by the species of Phoxinus: (4*) supraorbital canal in- 

 terrupted between nasal and frontal bones; (6) preopercular canal ending at middle of the 

 ascending arm of the preopercle: (7*) preoperculomandibular canal interrupted into man- 

 dibular and preopercular canals; (10*) breast scales deeply embedded in breeding males; 

 (12*) breast scales bearing a series of tubercles at its apical margin in breeding males; 

 (14*) scales on caudal peduncle bearing three or more tubercles at the scale's apical mar- 

 gin in breeding males: (17) orbital septum lower; (21) pharyngeal pad of occipital bone 

 bearing an anterior process. 



Nine species are recognized in Phoxinus herein. Species of this genus occur in Eurasia 

 and North America. See below for morphology, phylogenetic relationships, biogeography. 

 and systematics of this genus. 



Node D: This node unites three genera, Eupallasella, Rhynchocypris, and Lagowskiella, 

 as a monophyletic group with one synapomorphy: (18) orbital septum widely connected 

 to the dorsal aspect of the parasphenoid. 



Eupallasella Dybowski, 1916 bears two synapomorphies: (16) anterior margin of orbital 

 septum bearing an anterior process; (19) a cartilage present in front of the orbital septum 

 in adult. 



One species. Eupallasella percnurus (Pallas) is recognized by Howes (1985). This spe- 

 cies occurs in northeast China (Yang & Huang 1964) and Korea (Berg 1949). 



