Nothobranchius janpapi

description

Description. General body features illustrated by Figures 2 A – D. Morphometric and meristic characters of examined material are summarized in Table 3. Male: Small Nothobranchius species, maximum examined size 33.7 mm SL. General body shape laterally compressed. Greatest body depth at vertical in front of pelvic-fin origin (27.4 – 31.0 % SL). Greatest body width at pectoral-fin base with body progressively narrowing towards caudal-fin base. Dorsal profile slightly convex to straight from tip of snout to dorsal-fin origin, straight to slightly concave on caudal peduncle. Ventral profile convex from lower jaw to base of last anal-fin ray, straight to slightly concave on caudal peduncle. Caudal peduncle moderately deep, length 133 – 140 % of its depth. Anus situated directly in front of anal-fin origin. Head moderately long (25.6 – 30.6 % SL), laterally compressed, deeper than wide (head width 74 – 81 % of its depth). Snout distinctly pointed, smaller than eye diameter. Mouth supraterminal, slightly oblique in profile. Jaws subequal, lower jaw longer than upper, posterior end of rictus at same level or slightly ventral to centre of eye. Premaxilla and dentary with many irregularly dis

A review and redefinition of the subgenus Aphyobranchius Wildekamp, 1977, in the seasonal killifish genus Nothobranchius Peters, 1868 (Teleostei: Nothobranchiidae), from ephemeral wetlands of eastern Tanzania

diagnosis

Diagnosis. Nothobranchius janpapi belongs to the N. janpapi species group within the subgenus Aphyobranchius by presenting the following combination of characters in the male: light blue body colouration with narrow red scale margins and yellow-brown to yellow-green dorsum stripe; rearward positioned dorsal fin with predorsal length of 63.3 – 67.9 % SL and predorsal length 109 – 115 as percentage of preanal length; dorsal fin relatively small with low number of rays, 12 – 14; cephalic sensory system at supraorbital level in an undivided, slightly curved, almost flat, shallow groove with three exposed neuromasts and pronounced lobes (Fig. 3 a). Both sexes with central 2 – 3 rays of the caudal fin slightly elongated forming a mild posterior lobe (vs. central lobe absent). Nothobranchius janpapi is distinguished from the other members of the N. janpapi species group by male colouration of anal fin with slender orange-red distal band and narrow light blue margin (vs. slender yellow subdistal band with narrow red distal band); caudal fin base and proximal zone olive, with light grey to translucent subdistal band and narrow dark grey distal band (vs. base and proximal zone grey to light

A review and redefinition of the subgenus Aphyobranchius Wildekamp, 1977, in the seasonal killifish genus Nothobranchius Peters, 1868 (Teleostei: Nothobranchiidae), from ephemeral wetlands of eastern Tanzania

distribution

Distribution. Nothobranchius janpapi is endemic to seasonal freshwater habitats in coastal Tanzania and is the most common, but second most widespread, member of the Aphyobranchius subgenus, occurring mainly in the Ruvu and Rufiji river systems (Fig. 1). It occurs in the middle and lower reaches of the latter and throughout most of the former but dominantly in the lower reaches. The westernmost locality known to date is in the Kisaki area on the floodplain of the Mgeta River, a tributary of the upper Ruvu River system. There is currently a lack of range data available for the middle reaches of the Ruvu River, but this can probably be attributed to a lack of investigation in that area. The northern extent of distribution is in the southern part of the Wami River delta where it merges with the coastal plains associated with the Ruvu River. The southernmost occurrences are in the coastal floodplains immediately south of the Rufiji delta, probably extending to the lower Matandu River system where a population of what has provisionally been referred to as “ N. cf. janpapi ” is present. The affiliation of this southern population is presently being studied. A single, relatively isolated,

A review and redefinition of the subgenus Aphyobranchius Wildekamp, 1977, in the seasonal killifish genus Nothobranchius Peters, 1868 (Teleostei: Nothobranchiidae), from ephemeral wetlands of eastern Tanzania

materials_examined

Material examined. RMCA 77 - 16 - P- 19, holotype, male, 33.7 mm SL; – RMCA 77 - 16 - P- 20, female, 28.9 mm SL; – RMCA 77 - 16 - P- 21 - 23, 2 females, 28.2 – 28.6 mm SL; Tanzania: Ruvu drainage, Kwaraza, approx. 06 ° 41.8 ’ S, 38 ° 42 ’ E; R. Wildekamp, T. Steinfort, J. Lourens, R. van Haarlem; 12 June 1976; field code: T 76 - 8. Additional material examined. 1 male, 27.7 mm SL; Tanzania: Ruvu drainage, Kwaraza; 06 ° 40.818 ’ S, 38 ° 39.829 ’ E; B. Nagy; 12 January 2009; field code: TZN 09 - 4. – 1 male, 28.4 mm SL; Tanzania: Ruvu drainage, Soga; 06 ° 50.14 ’ S, 38 ° 50.80 ’ E; B. Watters, J. Rosenstock, M. Agnew, F. Larsen; 29 May 1998; field code: TAN 98 - 14. – 1 male, 32.6 mm SL; Tanzania: Ruvu drainage, Soga; 06 ° 50.19 ’ S, 38 ° 50.78 ’ E; B. Watters, R. Wildekamp, B. Cooper; 12 June 1997; field code: TAN 97 - 45. – 1 male, 32.0 mm SL; Tanzania: Rufiji drainage, Kitonga; 08 ° 03.110 ’ S, 39 ° 00.510 ’ E; B. Watters, B. Cooper, W. Bishopp; 29 May 2003; field code: TAN 03 - 22. – 5 males, 22.2 – 25.6 mm SL, 2 females, 21.1 – 23.5 mm SL; Tanzania: Ruhoi drainage, Ngulakula; 07 ° 48.073 ’ S, 38 ° 48.739 ’ E; B. Watters, B. Cooper, O. Schmidt; 4 June 2002; field code: TAN 02 - 1

A review and redefinition of the subgenus Aphyobranchius Wildekamp, 1977, in the seasonal killifish genus Nothobranchius Peters, 1868 (Teleostei: Nothobranchiidae), from ephemeral wetlands of eastern Tanzania