Gorongosa Killifish

description

Description. Morphology and general body shape similar to N. furzeri (Figs. 1 & 2, Table 1). A robust Nothobranchius species with a characteristic convex frontal region, in mature males sometimes exaggerated into a distinctive frontal hump. The dorsal fin 13 – 14 rays, anal fin 13 – 14 rays (up to 16 in females), pelvic fin 6 rays and pectoral fin 16 – 18 rays. In males, pectoral fins typically overlap with pelvic fins (50 % of the pectoral fin is beyond the anterior margin of pelvic fin). Pelvic fins reach or slightly overlap the base of the anal fin. The longest rays of dorsal and anal fins reach or extend beyond the anterior margin of the caudal fin. In females, the longest rays of the pelvic fin just reach the anal fin base. About 30 % of the pectoral fin extends beyond the base of the pelvic fin. The tip of female anal fin does not reach the caudal fin, but the dorsal fin sometimes reaches the caudal fin. The longitudinal series possesses 27 – 29 scales; one large male (50.2 mm SL) with 34 scales in the longitudinal series was recorded. Live colouration. Males. Colouration varies from deep red to light blue and appears to be continuous rather than falling into two discrete col

Nothobranchius kadleci (Cyprinodontiformes: Nothobranchiidae), a new species of annual killifish from central Mozambique

description

MZCS 08 / 92 19 ° 19.6 ' S 34 ° 18.5 ' E 24 173 33.5 50 The external morphology of Nothobranchius kadleci is similar to that of N. furzeri, but the two species clearly differ in their colouration (Figs. 2 & 3) and have apparently allopatric distribution. Many Nothobranchius species, including N. furzeri, occur in two distinct colour morphs. In other Nothobranchius species, more continuous colour variation is found (Wildekamp 2004). This appears to be the case in N. kadleci, with a continuous variation from fully red males with some light blue markings on body and fins to males with a larger extent of blue on their body and fins. Additionally, the amount of red also appears to increase with the age of the fish. Some female N. kadleci have irregular black dots on their bodies (especially at MZCS- 08 / 107, but also MZCS- 08 / 91) which is characteristic for some populations of N. orthonotus (especially in vicinity of the city of Beira), but lacking in all known N. furzeri populations. The Save River forms an apparent range boundary between N. kadleci (north of the Save) and N. furzeri (south of the Save). This is confirmed by a thorough sampling effort (Wood 2000; Terzibasi et al. 20

Nothobranchius kadleci (Cyprinodontiformes: Nothobranchiidae), a new species of annual killifish from central Mozambique

diagnosis

Diagnosis. Nothobranchius kadleci is distinguished from N. furzeri by the smaller depth of the dorsal fin (17.9 – 31.0 % SL vs. 27.4 – 37.7 % SL in N. furzeri in males, 14.9 – 17.6 % SL vs. 19.0 – 21.9 % SL in females) and smaller depth of the anal fin (17.4 – 25.8 % SL vs. 22.4 – 32.4 % SL in N. furzeri in males, 17.3 – 19.2 % SL vs. 19.3 – 24.5 % SL in females), larger preanal distance (64.0 – 65.8 % SL vs. 58.9 – 61.3 % SL in N. furzeri) in females and presence of red colour on gill membrane and lips and red pectoral fins (N. furzeri does not possess red colour on gill membrane and lips and typically have yellow pectoral fins), absence of black marginal band on caudal fin (present in some male N. furzeri), and a higher amount of red on caudal and dorsal fins and on body in males. It is distinguished from sympatric N. orthonotus (including putative N. kuhntae and N. mayeri) by the shape of the frontal region (convex in N. kadleci, flat in N. orthonotus), the presence of red pectoral fins with white margins, often with a bluish tint (N. orthonotus possess transparent or whitish pectoral fins with red margins), red background colour on the head covered with small to large light blu

Nothobranchius kadleci (Cyprinodontiformes: Nothobranchiidae), a new species of annual killifish from central Mozambique

distribution

Distribution. This new species was found in 12 populations from a relatively large area in central Mozambique, north of the Save River, including the basin of the Save, Gorongose, Pungwe and Zangue Rivers (Fig. 4, Table 2). The altitude of collections sites ranged from 24 – 82 m above sea level. The latitudinal extent of the range of N. kadleci is over 300 km primarily along the north-south axis. Habitats. All populations of N. kadleci were found in small temporary pools varying from 3.5 – 2150 m 2, with a maximum depth of 10 – 70 cm in 2008 and 50 – 100 cm in 2009, very turbid water and soft muddy bottom (Fig. 5, Table 2). Littoral vegetation was present in 50 % of the pools, with scarce Nymphaea sp. vegetation in two pools. Conductivity ranged from 68 – 300 ΜS. cm- 2 and water temperature during collection was 27.7 – 38.2 ° C. Sympatric fish species included N. orthonotus (10 cases), N. rachovii (2 cases), an unidentified small Barbus sp. (2 cases), Tilapia sp. (1 case), Protopterus sp. (1 case) and Clarias gariepinus (1 case).

Nothobranchius kadleci (Cyprinodontiformes: Nothobranchiidae), a new species of annual killifish from central Mozambique