Fishes of the lVester?i North Atlantic 79 



of axils of pelvics by a distance about half as great as distance from origin of first dorsal 

 to origin of caudal and about as long as interspace between the two dorsals. Interspace 

 between first and second dorsals about 1.5— 1.6 times as long as base of first dorsal. 

 Interspace between base of second dorsal and origin of caudal about as long as base 

 of second dorsal. Upper and lower origins of caudal about opposite one another; caudal 

 axis horizontal or bent slightly upward; upper margin nearly straight and nearly as 

 long as distance from origin of first dorsal to origin of second; lower posterior margin 

 evenly rounded, without separate lower lobe; height of caudal above termination of 

 axis about 1.3 times as great as depth below the latter. Pelvics broadly rounded out- 

 wardly, decreasing to narrowly blunted tips, their inner margins weakly concave, their 

 extreme length from origin to tip about twice as great as length of interspace between 

 first and second dorsals; their axils separated by a distance about as great as breadth 

 of mouth in females, but only about ^\^ that great in juvenile male. Claspers of mature 

 male slender, as in Rhinobatos^ their tips somewhat swollen, extending back about to 

 level of rear end of base of first dorsal. 



Rostral cartilage broad basally, tapering anteriorly to narrow tip close to ex- 

 tremity of snout; its lateral ridges low, inconspicuous, far apart at base but converging 

 toward tip. Anterior rays of pectorals extending for only a short distance anterior to 

 level of front of orbital region of cranium, thus falling far short of extremity of snout. 



Color. Preserved specimens olive to brownish gray above, without definite markings; 

 dorsals and caudal somewhat darker than general ground tint; margins of pectorals 

 and pelvics paler; space on either side of rostral cartilage also pale, possibly translucent 

 in life. Lower surface grayish or yellowish white, the posterior corners of pectorals and 

 tips of pelvics more or less dusky. 



Size. The largest specimen recorded was about 2 i inches long (540 mm),*^ but 

 it is not unlikely that Z. brevirostris may reach as great a size as Z. exasperata of the 

 Pacific, a length of about three feet.'" 



Developfnental Stages. It is probable that development is ovovivi parous, but 

 neither the embryos nor the newborn young have been reported. 



Habits. Nothing whatever is known of the habits of this Ray to distinguish it from 

 the Guitarfishes of the genus Rhinobatos. 



Range. Known so far from Brazil alone, where it has been taken near Rio de 

 Janeiro and near Bahia. Apparently it is not common though occasionally trawled in 

 some numbers. 



Synonyms and References: 



Rhinobatus {Syrrhind) brevirostris MuUer and Henle, Plagiost., 1841: 114, 192, pi. 36 (descr., meas., ill., 



Brazil); Castelnau, Anim. Nouv. Rares Amer. Sud, Poiss., 1855: 100 (listed, Rio de Janeiro); Dumeril, 



Hist. Nat. Poiss., I, 1865: 489 (descr., size, Brazil). 

 Platyrhina sinensis (in part) Gray, List Fish. Brit. Mus., j, 1851: 98 (specimen from Brazil, but not refs.). 

 Rhinobatus brevirostris Giinther, Cat. Fish. Brit. Mus., 8, 1870: 447 (descr., size, Brazilian specimen pre- 



69. Dumeril, Hist. Nat. Poiss., i, 1865: 490. 



7c. Ribeiro (Fauna brasil., Peixes, 2 [i] Fasc. i, 1923: pi. 12) gives an excellent photograph of a male with fully devel- 

 oped claspers but without stating the size. 



