112 



arch. The triangular morphology appears to be independent of this continuum, but may 

 also be an artifact created by a large notch in the posterior edge of the palate (see characters 

 #67 and 68). Thus, the pointed "Gothic arcfT described for Phoca vitulina and Pusa 

 hispida by Doutt (1942) may actually be a combination of an arched posterior edge with 

 a large triangular notch. 



An arched posterior edge of the palate is both plesiomorphic and common throughout the 

 Caniformia. This primitive condition is retained into both phocid subfamilies, and largely 

 typifies most species. A triangular morphology occurs independently among a few species 

 in both subfamilies: Phoca spp. among the phocines, and Leptonychotes, Lobodon, and 

 Monachus tropicalis among the monachines. The other apomorphic state, a straight 

 posterior edge, is found convergently in Odobenus and the clade of Histriophoca plus 

 Pagophilus. In contrast to the observations of Chapskii (1955a), polymorphism was 

 observed to be minimal for this character among the phocids. 



66) presence of posteriorly directed process in midline of posterior edge of palatine: 0 = 

 absent; 1 = present (Chapskii 1955a). 



In contrast to the notching of the posterior palatal edge present in many phocines (see 

 characters #67 and 68), Chapskii (1955a) noted a small, posteriorly directed process in 

 Histriophoca, Pagophilus, and occasionally in Phoca vitulina. This condition is primitive 

 among caniforms, with the loss of the process being a synapomorphy of Lutra and the 

 pinnipeds. But, among this group, only Mirounga leonina consistently regained the 

 posteriorly directed process. 



67) morphology of notching in posterior edge of palatine: 0 = rounded; 1 = triangular; 2 

 = incision; 9 = none (Ridgway 1972). 



The notching or incision of the posterior edge of the palate has been variously noted for 

 Phoca spp. and Pusa spp. (Doutt 1942; Chapskii 1955a; Burns & Fay 1970; Ridgway 

 1972). Such a condition does not seem to be typical among the remaining phocines (Doutt 

 1942; Chapskii 1955a; Ridgway 1972; de Muizon 1982a), although Burns & Fay (1970) 

 hint that Histriophoca may be polymorphic for this character. King (1956) describes a 

 small incision for Monachus monachus, which we would reclassify here as a small 

 triangular notch based on her Fig. 7 (page 230). 



The primitive condition for the Caniformia as a whole is the lack of any notching. This 

 agrees with the previous character, where a posteriorly directed process is postulated as 

 being plesiomorphic. Notching of any form is reasonably rare and largely restricted to the 

 phocids. The most common form is a triangular shape, occurring consistently in Mirounga 

 angustirostris and the clade of Lobodon plus Monachus spp., but appearing 

 polymorphically (with state 9) in a number of other pinnipeds. Monachus tropicalis 

 uniquely derives the incision, while a rounded notch was obtained only for Histriophoca, 

 and then only as a species polymorphism with a triangular notch. 



68) size of notching in posterior edge of palatine: 0 = small; 1 = medium; 2 = large; 9 = 

 absent (Chapskii 1955a). 



The notching present in the posterior edge of the palate of many phocids can have an 

 adverse effect on the determination of the shape of the posterior edge of the palate as a 



