6 



Taxonomic and systematic history 



The distinctiveness of the phocids has long been recognized. They were first accorded 

 familial status by Brookes (1828) and, except for minor transient alterations, the 

 membership of the family has remained the same ever since (although species assignments 

 are contentious in some cases; see Appendix A for the list of species recognized here). 

 Monophyly of this group has never been seriously challenged and appears to be universally 

 accepted today (de Muizon 1982a; Wyss 1988a). 



The higher level taxonomy of the phocids has been surprisingly stable in view of how 

 historically contentious their placement within the carnivores has been (see below). The 

 phocids are the only extant members of the superfamily Phocoidea (Smirnov 1908), or 

 those pinnipeds that are unable to turn the hind limbs forward on land. Together with the 

 Otarioidea (Smirnov 1908; sea lions, fur seals, walrus, and allied fossil forms), they 

 constitute the Pinnipedia (Illiger 1811). Although their arctoid affinities are readily accept- 

 ed (Flynn et al. 1988), the distinctiveness of all pinnipeds from the remaining fissiped 

 carnivores has led them to be viewed as a separate order (e.g., Scheffer 1958; Ewer 1973; 

 Corbet & Hill 1991), or, more commonly, as a suborder within the carnivores (e.g., Turner 

 1848; Flower 1869; Mivart 1885; Simpson 1945; King 1983). However, the possibility of 

 a diphyletic origin of the pinnipeds has led some workers to abandon a distinct Pinnipedia 

 altogether (e.g., McKenna 1969; Mitchell & Tedford 1973). 



Taxonomy within the phocids largely reflects the historically poorly described and largely 

 unresolved internal relationships of the phocids. Early taxonomies generally divided the 

 phocids into four main subfamilies [but see Allen (1880) for a more complete review]: 

 the Cystophorinae (Gill 1866; hooded and elephant seals), Lobodontinae (Gill 1866; 

 Antarctic seals), Monachinae (Trouessart 1897; Monachus spp.), and Phocinae (Gill 1866; 

 remaining northern hemisphere seals). Although this taxonomy is generally representative 

 of the major phocid types, the granting of equal taxonomic status to each group does not 

 appear to be justified. 



Throughout much of their taxonomic history, the Lobodontinae and Monachinae have been 

 alternately separated and rejoined, a fact indicating the general lack of distinctiveness 

 between the two taxa. Scheffer (1958), holding that the only real distinction between the 

 two taxa was one of geography, subsumed the two as tribes (Lobodontini and Monachini 

 respectively) within a newly defined Monachinae. 



The next major step involved the dismantling of the Cystophorinae by King (1966). The 

 Cystophorinae were erected largely on the basis of two features: a 2/1 incisor formula and 

 the possession of some form of inflatable nasal proboscis in the adult males [but see King 

 (1966) and Ridgway (1972) for additional minor similarities]. It continued to be recognized 

 despite numerous obvious differences between its two constituent genera {Cystophora and 

 Mirounga), including the morphology of the nasal sac and manner in which it is inflated 

 (Reeves & Ling 1981; King 1983; Kovacs & Lavigne 1986). Finally, King (1966) argued 

 that the two diagnostic cystophorine features likely arose via convergence and pointed to 

 a suite of 17 other cranial and post-cranial features that allied Cystophora with the 

 "northern" seals and Mirounga spp. with the "southern" seals. McLaren (1975) later 

 ascribed the convergent cystophorine features [also found in the fossil pinniped Allodesmus 



