Genus Galeus

Author: Rafinesque, 1810

Field Marks:
Usually firm-bodied scyliorhinids with caudal crests of enlarged denticles, usually rather long and wedge-shaped snouts, short labial furrows, subocular ridges virtually obsolete, large pectoral fins, large anal fin, elongated caudal fins, often barred and blotched colour pattern.

Diagnostic Features:
Body not tadpole-shaped, slender and subcylindrical to rather compressed, tapering slightly to considerably to caudal fin; body firm and thick-skinned, with well-calcified dermal denticles; stomach not inflatable; tail varying from fairly short to moderately long, length from vent to lower caudal origin about 2/5 to 5/6 of snout-vent length. Head slightly depressed, narrowly pointed-rounded in lateral view and somewhat wedge-shaped or not; head short to moderately long, between 1/4 and 1/5 to less than 1/5 of total length in adults; snout fairly short, to moderately elongated, 2/3 to about equal to mouth width, thick to rather thin and flattened, bluntly to almost acutely pointed in lateral view; snout not expanded laterally, broadly to narrowly rounded-parabolic and usually bell-shaped in dorsoventral view; ampullal pores not greatly enlarged on snout; nostrils of moderate size, with incurrent and excurrent apertures only partly open to exterior; anterior nasal flaps broadly triangular and rather low, without barbels, well separate from each other and falling well anterior to mouth; internarial space about 0.7 to 1.2 times the nostril width; no nasoral grooves; eyes virtually lateral on head, subocular ridges below eyes narrow or obsolete; mouth angular or semiangular, moderately long, with lower symphysis well behind upper so that upper teeth are exposed in ventral view; labial furrows present along both upper and lower jaws, these very short to moderately long but ending well behind level of upper symphysis of mouth; branchial region not greatly enlarged, distance from spiracles to fifth gill slits 1/3 to 1/2 of head length; gill slits lateral on head. Two equal-sized dorsal fins present, origin of first varying from over the first third of the pelvic bases to about over their insertions; origin of seond dorsal varies from about over to slightly behind the anal midbase; pectoral fins large, their width somewhat less to considerably greater than mouth width; inner margins of pelvic fins not fused or variably fused and forming an 'apron' over claspers in adult males; claspers short to moderately long, fairly thick and distally pointed and often twisted, extending from less than a fifth to about half of their lengths behind the pelvic fin tips; anal fin large and more or less elongated, about as large as pelvic fins or larger, and considerably larger than the dorsals; its base length 1.6 to slightly over 3 times second dorsal base; origin of anal close to far behind pelvic bases, and its insertion separated from lower caudal origin by a narrow notch to a broad space nearly equal to the anal base; caudal fin more or less elongated, over or somewhat less than a fourth of total length in adults. A well-developed crest of denticles on the dorsal caudal margin and sometimes the upper edge of the caudal peduncle, and in some species on the preventral margin and lower edge of the caudal peduncle, dorsal crest flat on its upper surface and symmetrical; small median denticles between upper crest denticles usually in less than five rows; supraorbital crests absent from cranium. Colour light grey or brown, with or without a conspicuous colour pattern of dark saddles and blotches.

Remarks:
Orkin (1952) advocated the rejection of Galeus Rafinesque, 1810 because of prior selection of a type species, Galeus mustelus, by Jordan and Evermann (1896), which antedates Fowlers' (1908) selection of G. melastomus Rafinesque, 1810, as the type of Galeus. If Orkin's recommendation is followed, Galeus Rafinesque, 1810 becomes a junior synonym of Mustelus Linck, 1792 and Pristiurus Bonaparte, 1834, must be used for this genus. As a present expedient I prefer to follow Fowler's type designation because G. melastomus is the only species of Galeus mentioned in Rafinesque's (1810) account that has a description. The other three species, Galeus vulpecula, G. mustelus and G. catulus, although "identifiable" (Orkin, 1952), are mentioned in name only, without references or characters. Since Galeus has received considerable usage since Bigelow and Schroeder's (1948) review of the genus (up to and including its recent revision by Springer, 1979), continued use of Galeus is preferable to its substitution by Pristiurus for promoting nomenclatural stability. Pristiurus has had considerable usage in the older literature. The subgenus Figaro was proposed by Whitley (1928) for a new Australian catshark, Pristiurus boardmani that differed from well-known species of Galeus by having an additional crest of enlarged denticles on the preventral caudal margin. Whitley (1939) raised the rank of Figaro to genus, but Fowler (1941) and Bigelow and Schroeder (1948) synonymized it with Galeus. Springer (1966) recognized Figaro without comment, but later included it in Galeus. Recently Chu et al. (1983) revived Figaro for Pristiurus boardmani Whitley, 1928, Dichichthys melanobranchius Chan, 1966, and the new Figaro piceus Chu _ al. 1983 (a possible synonym of D. melanobranchius); they defined the genus primarily by its suboaudal denticle crest. Two additional species have subeaudal crests: Pristiurus murinus Collett, 1904, usually placed in Galeus; and Parmaturus pilosus Garman, 1906, the type-species of the genus Parmaturus. If all these species are placed in the genus Figaro it becomes a heterogeneous assemblage defined by a single character; moreover, Figaro becomes a junior synonym of Parmaturus, and species of Parmaturus without the subsaudal crest (P. xaniurus and P. campechensis) become orphans, even though they are phenetically more similar to P. pilosus and D. melanobranchius than to P. boardmani. Hence a temporary solution to the problem, that advocated by Springer (1979), is adopted here: to not recognize Figaro and include P. boardmani in Galeus and D. melanobranchius and F. piceus in Parmaturus. The problem with Springer's (1979) arrangement is that Galeus and Parmaturus may ultimately prove to be generically inseparable. Although typical species of Galeus, such as G. melastomus, are strongly differentiated from typical Parmaturus such as P. pilosus, some of the other species in these genera, including G. boardmani, G. murinus, G. schultzi, and P. melanobranchius, are more or less intermediate. Hence the characters separating these genera as given in the key to genera and in the diagnostic features may not work for all species. Reviews of this genus are in Bigelow and Schroeder (1948), Springer (1966), Springer and Wagner (1966), and Springer (1979). There may be an undescribed species of Galeus, of more typical form than G. boardmani, in Australian waters.

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