The Rare “Furred-Tongue” Uraspis Uraspis (Gunther) from South Africa, and Other New Records from There
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DEPARTMENT OF ICHTHYOLOGY Rhodes University, Grahamstown ICHTHYOLOGICAL BULLETIN No. 26 ISSUED OCTOBER, 1962 The Rare “Furred-Tongue” Uraspis uraspis (Gunther) from South Africa, and other new records from there by J. L. B. SMITH Research Professor and South African Council for Scientific and Industrial Research Fellow in Ichthyology Illustrations by Margaret M. Smith (Published by the Department of Ichthyology, Rhodes University, Grahamstown, South Africa) ACKNOWLEDGMENTS The main funds covering numerous extensive expeditions in the Western Indian Ocean, on which much of this work is based, were provided by the South African Council for Scientific and Industrial Research, who also made a special grant for the publication of this Bulletin. We are grateful to Rhodes University for a special grant to cover postages on type specimens. We acknowledge also extensive facilities and assistance received in the Western Indian Ocean from the authorities of Mozambique, Tanganyika, Kenya, Zanzibar, Pemba, Seychelles and all islands (excepting French terri tories) there, also from numerous private persons and collectors. I am greatly indebted to Mr. R. Liversidge, M.Sc., of Port Elizabeth, for the specimen of Uraspis and for a photograph of the live fish. Special thanks are due to Dr. W . I. Follett, California Academy of Sciences, and to Dr. W. Klausewitz, Frankfurt, for the loan of valuable types. To Dr. A. W right, of Durban, we are indebted for many valuable specimens. ft The Rare "FURRED-TONGUE" URASPIS URASPIS (Gunther), from South Africa, and other new records from there (W ith Plates 73 and 74) by J. L. B. SMITH Research Professor and South African Council for Scientific and Industrial Research Fellow in Ichthyology, Rhodes University, Grahamstown, South Africa. The strong westerly Indian Ocean sub-Equatorial Current washes the tip of Madagascar and strikes Africa at about Cape Delgado. Here it divides, the southerly branch, a powerful stream, known as the Mozambique current, flows southwards along the coast of East Africa, its effects distinct as far as the Cape of Good Hope. One result of this warm current is that tropical species are carried further south than almost anywhere else in the world, and species commonly occurring only in low latitudes are constantly being found surprisingly far south. During early 1962 the flow of the Mozambique current was unusually strong and temperatures far above normal have been recorded along the South African coast to and beyond Algoa Bay. W ith this there have been numerous discoveries there of tropical species not before found south of Mozambique. Below are described the most outstanding. FAMILY CARANGIDAE. During the past century at odd mostly long intervals there have appeared records and descrip tions of certain rather small Carangid fishes, characterised by edentate white furred tongue and inside of mouth, and sometimes by the unusual armature of the straight part of the lateral line. These have almost always been single specimens, most rather small. Until recently records have been from the western north Atlantic (5), Red Sea (1), Persian Gulf (1), Western Pacific (5), Hawaii (3), Australia (2). In 1961 W illiams reported 3 small specimens from equatorial East Africa, the first from the western Indian Ocean. Recently a specimen has been found at Algoa Bay, the first from South Africa, fortunately still alive, and of particular interest as being the smallest ever described. These fishes fall in the genus Uraspis Bleeker, 1855.* Uraspis Bleeker, 1855. The Furred-Tongues. (Plate 73). T ype Uraspis carangoides B leeker, 1855 (E. In die s) = Caranx uraspis Gunther, 1860 (new name, carangoides homonym in Caranx). In most respects similar to Caranx Lacepede 1802, differing in the absence of teeth from palate and tongue, in having a thick white membrane on tongue, roof and floor of mouth (the rest dark), and in the different nature of the armature of the straight part of the lateral line, the scutes sometimes more or less ankylosed, the lateral spinose projection of each with age more keel-like than in Caranx and with the apices sometimes directed forwards. Snout rather blunt. A sharp median predorsal ridge to snout. In each jaw irregularly curved sharp stout or slender caniniform teeth, usually biserial or triserial in juveniles, uniserial with age, palate and tongue edentate. Two dorsal fins, the first of 6-8 feeble spines, front 2 anal spines mostly obsolete at relatively early stage. Pectoral short in the young, longer with age, pelvics may be elongate in young, shorter with age. Breast naked. These fishes plainly undergo considerable changes with growth and as they are widespread in the oceans but nowhere more than occasional rarities, most specimens found have been named as new, the latest, juveniles from East Africa described by W illiams 1961, 66. Although these East African specimens agree in all determinable characters of any importance with the diagnosis of U.carangoides Blkr, 1855 ( = U.uraspis Gunther, 1860) W illiam s describes them as new. He has taken a great deal of trouble to give a detailed and critical' analysis on the basis of a world review, but his references to literature are in an unusual form in convenient to others. He had apparently not known of the Australian specimens, for otherwise, apart from their identity with uraspis Gnthr, he could scarcely have failed to see that his own speci mens are identical with Caranx hullianus McCulloch, 1909 from Australia (Sydney), thoroughly described and well figured from a specimen 112mm length (PI 73, C). Scute counts as quoted by W illiams 1961 are rather variable, but that is probably due to different methods of counting. The number of protruding spines is always lower than the total of individual scutes of all sizes taken from the origin of the straight part of the L.l. to its end on the tail. *S ee Note p. 508 505 PLATE 73 A - D . Uraspis uraspis (Gnthr). A. 56mm (Algoa Bay). B. Same, alive. (Photo: R. Liversidge), C. 112mm. After McCulloch (Australia). D. Type of U.reversa J. E. & W. 315mm (Hawaii). E. U. helvola (Forster) 235mm (Red Sea). Type of Caranx micropterus Ruppell, 1835. The overall systematic picture involving the various stadia from the Indo-Pacific is complicated by comparable specimens from the Atlantic, all so far identified as Uraspis Heidi Fowler, 1938. These agree in almost every respect w ith uraspis Gunther, 1860, and while Williams maintains his w akiyai 1961 as distinct from Heidi Fowler, the data leaves only the following distinction, quoted from W illiams 1961, 83: “ (a) Dark cross bands on body do not reach on to second dorsal and anal fins Heidi (A tla n tic ) (b) Dark cross bands on body reach on to the second dorsal and anal fins w akiyai (Indo-Pac).” This is a slender and scarcely tenable basis for differentiation at specific level in Carangid fishes where banding is a common juvenile phase and lost at highly variable stages in growth. After an exhaustive study of descriptions, including the Australian specimen, of the data compiled by W illiams, of my own specimen and of one of the types of Uraspis reversa Jordan, Evermann & W akiya, 1927 from Hawaii (kindly lent by Dr. W . I. Follett), it does not seem possible to distinguish clearly b e tw e e n uraspis Gunther, 1860, hullianus McCulloch, 1909, Heidi Fowler, 1938 and w akiyai W illiams, 1961. None of the characters on which different species have been based, i.a. uniserial or biserial teeth, antrorse or retrorse scute points, variation in fin and gillraker counts and lengths of pectoral and pelvics, appear to be singly of significance at specific level. They are accountable as develop mental change and to not unusual variability in Carangid fishes. W illiam s’ view that uraspis G u n th e r is inadequately defined because the type is missing is scarcely tenable. The original description w ith later material for reference amply defines the species. Caranx helvolus Forster, 1833 plainly falls in this genus. It was stated by the author to have been found at Ascension Island, Atlantic, but most investigators cast doubt on this, and it is signifi cant that all further comparable specimens have come from the Red Sea and Indo-Pacific.* W illiams 1961, 83 distinguishes helvola Forster, from Heidi Fowler, and w akiyai W illiams (which latter fall in uraspis Gnthr, as here defined): (a) Teeth in jaws biserial, except that posteriorly in lower jaw may be uniserial. Majority of points of lateral line scutes directed anteriorly. D ark cross bands on b o d y ................................................................................................ (uraspis) (b) Teeth in jaws uniserial. Points of lateral line scutes normal, i.e. directed posteriorly. No cross bands on body ............................................... Helvola" Unfortunately both the small S. African specimen and the 315mm Hawaiian fish described below cut clean across this differentiation for while the smaller has pleuriserial teeth, its scute points are lateral; and the larger has uniserial teeth but also antrorse scute points. By kindness of Dr. W. Klausewitz I have been able to examine the 235mm type of Caranx micropterus Ruppell, 1835 from the Red Sea. This is in excellent condition and is described and shown below. W hile clearly congeneric with the other specimens described here, it differs funda mentally, and agrees with the general diagnosis of helvola Forster. These two apparent forms are so closely related in almost all general features and meristic counts that were it not for the fact that differences show clearly from the earliest known stadia, the possibility of sexual dimorphism might be suspected. From available data the two appear to be distinguishable at all stadia as follows: A. Pelvic always longer than half length of pectoral. Some teeth distinctly and strongly curved.