69 



In Phoximis, the kinethmoid-supraethmoidal ligament connects with posterodorsal side of 

 the kinethmoid and with anterior side of the supraethmoid. The kinethmoid-maxillary li- 

 gament connects with the dorsolateral side of the kinethmoid and with a anterior process 

 of the maxilla. The kinethmoid-premaxillary ligament connects with the anterior portion 

 of the kinethmoid and with anterior side of the premaxilla. The position of the kineth- 

 moid is flexible. When mouth opens, the kinethmoid moves ventroanteriorly; while mouth 

 is closed, the kinethmoid moves back posterodorsally. 



The kinethmoid is slender and crescent in shape. In P. phoxinus, erythro gaste r, oreas, is- 

 sykkulensis, tennesseensis, and cumberlandensis, the distance between its ventral and dor- 

 sal margins is longer than the width between its two lateral margins (left and right margins) 

 (TS 35[1]) (Fig.35A, C, E). In P. neogaeus, brachyurus, and eos, however, the bone is 

 short and robust, its dorsal portion is wider than its ventral portion (TS 35 [0]; Fig.35B, 

 D). 



The dorsal edge of the kinethmoid is forked or notched. In P. cumberlandensis and erythro- 

 gaster, its anterior dorsal edge is deeply forked (TS 36[1]; Fig. 35 A, C); the fork is deep 

 and narrow, the depth of the fork is about one third of the bone length (dorsal- ventral). 

 In P. brachyurus, phoxinus, neogaeus, eos, tennesseensis, issykkulensis, and oreas, the an- 

 terior dorsal margin of the bone is shallowly notched, the notch is wider and about one- 

 sixth of the bone length in depth (TS 36[0]; Fig.35B, D, E). In the outgroups, the dorsal 

 margin of the kinethmoid is shallowly notched. Based on the outgroup comparison, a shal- 

 lowly notched dorsal margin of the kinethmoid is therefore interpreted as plesiomorphic, 

 the deeply forked dorsal margin of the bone as apomorphic condition. 

 Posteriorly, the kinethmoid is concave at its middle portion in most species of Phoxinus 

 (TS 37[0]) except P. brachyurus and eos. In the latter two species, the kinethmoid is not 

 concave but slightly convex at its middle portion of the posterior side (TS 37[1]). A for- 

 amen from the anterior side to the posterior side of the bone is present in P. neogaeus and 

 phoxinus (TS 38[1]; Fig.35D, E). The foramen is not observed in all other Phoxinus spe- 

 cies (TS 38[0]) and in the outgroups. 



A notch is present at the ventral edge of the kinethmoid in P. erythrogaster (TS 39[1]; 

 Fig.35A). The notch is not observed in other species of Phoxinus and in the outgroups 

 (TS 39[0]; Fig.35B-E). 



Supraethmoid (Fig.36A-E). In cyprinids, the supraethmoid is a single dermal bone lo- 

 cated in front of the paired frontals. Its ventral side is sutured to the dorsal side of the 

 mesethmoid. The shape of the supraethmoid is variable in minnows; it might be narrow 

 (e.g., Barilius), or "extending so much that it may be visible on the ventral aspect of the 

 skull" (e.g., Labeo) (Ramaswami 1955a). In some genera of the family Cyprinidae (e.g., 

 Aristichthys), there is a small median fontanelle between the supraethmoid and the fron- 

 tal (Ramaswami 1955a). 



In Phoxinus, the supraethmoid is thin and slightly concave at the middle portion of its 

 dorsal aspect, and more or less rectangular-shaped. The lateral portion of the supraeth- 

 moid roofs the anterior part of the olfactory capsule. Both the anterolateral and the ante- 

 rior margins are concave in all Phoxinus species, and the posterior margin is concave in 

 most species of Phoxinus. 



