Field Identification Guide to the Living Marine Resources in Kenya
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Batoid Fishes 68 BATOID FISHES The ‘‘Guide to Orders and Families’’, includes a total of 4 Orders and 7 Families. The latter are arranged by order using the classification adopted by Eschmeyer & Fricke (2011) which best reflects current use. Page numbers refer to those families that are treated in more detail in the species identification guide. The ‘‘Guide to Species’’, includes 19 species belonging to 7 families. TECHNICAL TERMS AND MEASUREMENTS pectoral fin alar spines (in males) thorns of median row 1st spiracle dorsal fin orbit nd pelvic fin, anterior lobe 2 dorsal fin alar thorns pelvic fin, posterior lobe caudal fin clasper of males lateral tail fold inner margin of length pelvic fin of snout, preorbital dorsal view axil of pectoral fin length of disc length of snout, mouth preoral anus width of disc nasal apertures length of tail ventral view gill slits Guide to Orders and Families GUIDE TO ORDERS AND FAMILIES 69 Order PRISTIFORMES – Sawfishes § Body shark–like with a saw–like elongated snout bearing a row of strong lateral teeth on each side. PRISTIDAE Page 72 Sawfishes § To 7.3 m. Demersal in shallow marine waters and estuaries, enters freshwaters. Two species are included in the Guide to Species. snout extremely prolonged, blade–like, armed with tooth–like structures Order TORPEDINIFORMES – Electric rays § § Pectoral fins greatly expanded and fused with head and trunk, forming a large oval disc; tail stout, without a spine. A large electric organ on each side of head, usually visible through the skin as a pattern of hexagonal markings. TORPEDINIDAE Page 72 Electric rays §§ To 1.3 m. Demersal, from shallow waters to depths of 200 m. One species is included in the Guide to Species. electric organ on each side of head Order RAJIFORMES – Guitarfishes and Skates § Body elongate and shark–like with pectoral fins expanded and fused with head and trunk; tail stout not marked off from body, and without a spine. RHINOBATIDAE Page 73 Guitarfishes § To 3 m. Demersal, in shallow coastal waters. Two > species are included in the Guide to Species. / body elongate and shark–like without a distinct lowercaudal lobe fin Batoid Fishes 70RAJIDAE Page 73 Skates § usually 2 reduced dorsal fins and a reduced caudal fin To 65 cm TL. Demersal, rare in tropical shallow waters or near coral reefs. One species is included in the Guide to Species. disc quadrangular to rhomboidal; mouth transverse to arched, with numerous teeth; 5 pairs of ventral gill slits oftenskin prickly in a row in alongmost species,midline the of prickles back Order MYLIOBATIFORMES – Stingrays – Butterfly rays – Manta rays § Pectoral disc rhomboid, oval, or triangular in outline, elaborated into shaped wings in some forms; tail moderately stout to very slender; most species have one or more saw–edged spines or stings on the dorsal surface of the tail. DASYATIDAE Page 74 no dorsal or Stingrays § caudal fins To 2 m disc width. Demersal, in coastal marine waters, enters freshwaters. Seven species are included in the Guide to Species. 1 or more poisonous spines GYMNURIDAE Page 76 Butterfly rays § To 2.5 m disc width. Demersal, inshore waters and offshore banks. One species is included in the Guide to Species. disc at least 1.5 times broader than long tail slender shorter than disc spine usually present Guide to Orders and Families 71 MYLIOBATIDAE Page 76 Eagle rays §– Cownose rays § Manta rays § §– Devil head marked off lobes from trunk rays § 1 or 2 subrostral Myliobatinae: – often swim above the bottom in coastal waters. Two to 2.3 m disc width; demersal, but Mobulinae: species are included in the Guide to Species. at least 6.7 m disc width; pelagic, in coastal and oceanic waters. Three species are included in the Guide to Species. spine present in cephalic fins some species Myliobatinae Mobulinae Batoid Fishes 72 - Pristidae - Torpedinidae PRISTIDAE § Pristis pectinata Sawfishes FAO names: § § Smalltooth sawfish (En) Local name(s): Latham, 1794§ § Poisson–scie tident (Fr) Habitat: N: Papa busefu, Papa upanga; S: entersPapa upanga freshwater. (M/K). Fisheries: Shallow bays, lagoons and estuaries; Distinctive Characters: Bottom trawls, Lines. Long, flat, blade–like rostrumlower lobe. with 24 to 32 pairs of evenly spaced teeth Colour:along edges; caudal fin large and oblique with no yellowish below. Underside of head Size: Dark grey to blackish above, white to To 760 cm Pristis zijsron FAO names: § Longcomb sawfish (En) Local name(s): Bleeker, 1851 § § Habitat: N: Papa busefu, Papa upanga; S: Papa upanga (M/K). Fisheries: a ' Distinctive Shallow Characters: waters; entersRostral freshwater. teeth of basal Bottom trawls, Lines. Colour:pairs distinctly more spaced than anterior pairs; sub–caudal lobe absent. Greenish–grey above, white below. Size: To 730 cm TORPEDINIDAE § Torpedo sinuspersici Electric rays FAO names: § Variable torpedo ray (En) Local name(s): Olfers, 1831 § Taa § Habitat: Inshore N:waters Shepwa over kifizasandy mkonobottoms; S: down (M), Taa (K). Fisheries: Distinctiveto 200 m. Characters: Bottom trawls, Hooksst and Line. Eyes smaller than spiracles; at least half of the 1 dorsal fin behind Colour:posterior end of pelvic–fin base; small caudal fin; papillae around the spiracles. blackish Brightbackground colour dorsally. pattern of cream or golden circles and irregular marks on dark red, brown or Size: To 90 cm (DW), 130 cm (TL) Guide to Species RHINOBATIDAE Rhinobatidae - Rajidae - 73 § Shovelnose rays § Guitarfishes– Rhina ancylostoma FAO names: § Angelot § Bowmouth guitarfish (En) Local name(s): Bloch & Schneider,§ 1801 § (Fr) § § Habitat: N: Papa kiharere; S: Papa wame (M), Papa usingizi (K). Fisheries: Inhabits Bottom coastal trawls. areas and on coral reefs, Distinctiveclose inshore Characters: from 3 m to 90 m. Snout rounded; heavy Colour:ridges with greatly enlarged denticles on back, over eyes and spiracles. Grey above, white below; numerous white spots dorsally on fins, body and tail; black spots on Size: head and shoulders but no eyespots or ocelli. To 270 cm (TL) Rhynchobatus djiddensis FAO names: § § Giant guitarfish (En) Local name(s): (Forsskål,§/Simbe 1775)§ Poisson paille à pois (Fr) wame§ § § Habitat: N: Papa kiharere ; S: Papa Fisheries:(M), BottomPapa usingizi trawls. (K). Distinctive Coral Characters: reefs, close inshore down to 50 m. Snout pointed and lower Colour:caudal lobe short; mouth small and containing flattened, pavement-like teeth. Olive-green above, white below; large black eyespots on pectoral–fin bases; a distinctive Size: black cross between the eyes, and rows of small white spots on upper body. To 300 cm (TL) RAJIDAE Skates § Raja miraletus FAO names: Brown ray § Raie miroir § (En) Local name(s): Linnaeus, 1758 (Fr) Habitat: Soft bottoms of the shelf and the N & S: No information. Fisheries: Bottom trawls. Distinctiveuppermost slopeCharacters: from 17 Snoutto 300 shortm. and bluntly Colour:pointed; disc angular; upper surface prickly only in young, nearly smooth in adults; underside smooth. Upper surface ochre to reddish–brown with scattered dark spots, underside white; two bright blue eye–spots centered on the pectoral bases; may have a small dark spot on tip of snout. Size: To 64 cm (TL) - Dasyatidae Batoid Fishes 74 DASYATIDAE Stingrays § Himantura gerrardi FAO names: § Sharpnose stingray (En) Local name(s): (Gray, 1851) Habitat: Shallow N: inshore Shepwa watersyedatuvi; over S: Taa sandy nyenga, and Taa karuwe (K). Fisheries: Distinctivemuddy bottoms Characters: down to 50Disc m. slightly wider than Lines, Seines, Bottom trawls. long, mostly naked, with a mid–dorsal band of small flattened denticles in adults, extending on to Colour:tail base; tail several times longer than disc without transverseupper or lower bands folds. of dark and light brown on tail Light brown above, white below; numerous (may be obscure on large individuals). Size: To 200 cm (TL) Himantura uarnak FAO names: § § Honeycomb stingray (En) Local name(s): (Gmelin,§ 1789)Taa chui§ Pastenague léopard (Fr) Taa karuwe§ Habitat: N: Shepwa tuvi; S: (M), Fisheries: (K). Distinctive Coastal Characters: environments down to 50 m. Lines. Snout sharply pointed; disc with narrowly rounded outer corners; tail long, slender and nearly 3 times body length when intact, with no caudal finfolds; disc slightly wider than long, without thorns but with band of Colour:flat denticles along midback (in adults); usually 1 medium–sized sting on tail. Conspicuous dark spots on a light brown disc;tail marked spots well–spacedwith bands of in black young and but white. crowded to Size: form a reticulated pattern in adults, white ventrally; To 600 cm (TL) Neotrygon kuhlii FAO names: § Blue–spotted stingray (En) Local name(s): (Müller & Henle,§ Taa 1841) nyenga § Taa karuwe§ Habitat: N: Shepwa yeda; S: , Fisheries: (K). Distinctive Rather Characters: deep coastal Snout waters very down short to 90 and m. Lines, Bottom trawls. broadly angular; disc slightly wider than long, largely naked; tail naked, length equal to, or slightly Colour:greater than disc; a small dorsal finfold above the ventral fold; lower tail fold slender. Disc reddish–brown with blue centered brightwhite rings.ocelli and scattered black spots dorsally, white ventrally; tail with conspicuous black and Size: To 70 cm (TL) Dasyatidae - Guide to Species 75 Pastinachus sephen FAO names: Cowtail stingray § § (En) Local name(s): (Forsskål, 1775) Pastenague plumetée (Fr) Habitat: N: Shepwa shepwekuti; S: Taa (M), Taa maji (K). Fisheries: Coastal Bottom waters trawls. in lagoons, reef flats, and Distinctivereef faces and Characters: estuaries down to 60 m. A large, plain, dark stingray with an angular snout and pectoral disc; tail long and broad–based, less than twice body length, and with no upper caudal finfold but with high lower caudal finfold, 2 to 3 times of tail depth butstingrays. not reaching tail tip; no large thorns; 1 or 2 long Colour:stings on tail, further behind tail base than in most Disc dark–brown or black above, white below; tail black with no conspicuous markings.