Galeus

Blackmouth catshark Galeus melastomus, photographed by Pierluigi Angioi.


Belongs within: Carcharhiniformes.

Galeus is a genus of catsharks with a caudal crest of enlarged denticles and large pectoral fins (Compagno 1984).

Characters (from Compagno 1984): 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 second 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.

<==Galeus Rafinesque 1810 [incl. Figaro Whitley 1928, Pristidurus Bonaparte 1838, Pristiurus Bonaparte 1834] C84
    |--*G. melastomus Rafinesque 1810 C84 (see below for synonymy)
    |--G. arae (Nichols 1927) (see below for synonymy) C84
    |--G. boardmani (Whitley 1928) [=Pristiurus (*Figaro) boardmani; incl. Figaro boardmani socius Whitley 1939] G84
    |--G. eastmani (Jordan & Snyder 1904) [=Pristiurus eastmani] G84
    |--G. murinus (Collett 1904) [=Pristiurus murinus, G. melastomus murinus; incl. P. jenseni Saemundsson 1922] C84
    |--G. nipponensis Nakaya 1975 C84
    |--G. piperatus Spriner & Wagner 1966 C84
    |--G. polli Cadenat 1959 C84
    |--G. sauteri (Jordan & Richardson 1909) [=Pristiurus sauteri] C84
    `--G. schultzi Springer 1979 C84

Nomina nuda: Galeus catulus Rafinesque 1810 C84
             Galeus mustelus Rafinesque 1810 C84
             Galeus vulpecula Rafinesque 1810 C84

Galeus arae (Nichols 1927) [=Pristiurus arae; incl. G. arae antillensis Springer 1979, G. cadenati Springer 1966, G. arae cadenati] C84

*Galeus melastomus Rafinesque 1810 C84 [incl. Squalus annulatus Nilsson 1832 C84, Scyllium artedii Risso 1820 C84, Pristiurus atlanticus Vaillant 1888 C84, Squalus (Scyliorhinus) delarochianus Blainville 1816 (n. n.) C84, Scyllium melanostomum Bonaparte 1834 C84, Pristiurus melanostomus PP64, Sq. prionurus Otto 1821 C84, Pristiurus souverbiei LaFont 1866 C84]

*Type species of generic name indicated

REFERENCES

[C84] Compagno, L. J. V. 1984. FAO Species Catalogue vol. 4. Sharks of the World: An annotated and illustrated catalogue of shark species known to date. Part 2—Carcharhiniformes. United Nations Development Programme, Food and Agriculture Organization of the United Nations: Rome.

[PP64] Peres, J. M., & J. Picard. 1964. Nouveau manuel de bionomie benthique de la mer Mediterranee. Recueil des Travaux de la Station Marine d'Endoume, Bulletin 31 (27): 5–137.

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