Tropheops kamtambo Li, Konings & Stauffer, 2016, new species

Tropheops kamtambo, new species

Fig. 6 A–C

Pseudotropheus elongatus ‘reef’, Ribbink et al. 1983 Tropheops sp. ‘ elongatus reef’, Konings 2007

Holotype. PSU 12771, adult male, 90.2 mm SL, S 13°46.240’, E 34°57.770’, Chimwalani Reef, Lake Malaŵi, Malaŵi, Africa, 12 Oct. 2006, A. F. Konings.

Paratypes. PSU 12772, 22, (58.7 mm – 92.6 mm SL), same data as holotype.

Diagnosis. The steeply sloped vomer (76.8° in holotype), a small mouth with retrognathic jaw and the presence of bicuspid teeth in the outer rows of the oral jaws and enlarged conical teeth at the back of the jaws place this species in Tropheops. Tropheops kamtambo (BD 26.6–30.8% SL) cannot reliably be distinguished from other Tropheops spp. on body depth (23.6–34.5%). Breeding male T. kamtambo have a blue ground coloration, while those of T. biriwira are green/light blue. Female T. kamtambo have a distinct black submarginal band on the dorsal fin, which is absent in females of T. kumwera and T. biriwira. Tropheops kamtambo can be distinguished from other Tropheops spp., except T. kumwera and T. biriwira, by the presence of fewer tooth rows (range 3–5 vs. 6–8) on both upper and lower jaws. The smaller eye (HED 26.3–30.2% HL; VED 24.0–29.7% HL) distinguishes T. kamtambo from T. biriwira (HED 30.8–40.4% HL; VED 29.6–35.4% HL). Tropheops kamtambo generally has a deeper head than T. kumwera (HD 79.4–97.1% HL vs. HD 70.2–84.5% HL in T. kumwera).

Description. Morphometric and meristic data in Table 5. Elongate species (BD 26.6–30.8% SL) with greatest body depth at fifth or sixth dorsal-fin spine. Dorsal body profile with gradual downward curve to soft-rayed portion of dorsal fin then more acute curve to posterior origin of dorsal fin, gradual taper to caudal fin; ventral body profile between pelvic and anal fins flat with upward curve from anterior point of anal fin to caudal fin. Head profile convex between snout tip and interorbital area, with premaxillary pedicel about 80–90° (82.7° in holotype) angle with body axis; dorsal head profile rounded to dorsal-fin origin. Teeth in outer rows bicuspid with large unicuspid teeth on posterior dentigerous arms of premaxilla, all inner rows tricuspid. Dorsal-fin spines progressively longer posteriorly from first to fourth spine, last spine slightly longer than fourth, and first spine about one fourth length of last spine. Soft dorsal fin with subacuminate tip, fourth ray longest, reaching to base of caudal fin in both male and female. Pectoral fin rounded, paddle-shaped. Anal fin with 3 spines progressively longer posteriorly; fourth ray longest, reaching to 1/3 of caudal fin in both males and females. Caudal fin subtruncate to emarginate. Pelvic fin not to anal fin in females; length in adult males to anal-fin base.

Flank scales large, ctenoid; abrupt shift to small cycloid scales on breast and belly; cheek with 4–6 (mode 5) rows of small scales. Dorsal fin and anal fin with narrow proximal band of tiny scales; tiny scales on 2/3 of caudal fin.

Color notes and photos of live breeding adults (PSU 12773).

Males in territorial color with blue ground coloration and 9–10 distinct black bars, posterior 1–3 bars often vague. Head black with 2 dark blue interorbital bars; throat light blue; cheek and preopercle dark blue. Anal fin dark gray/black with 4–6 orange ocelli. Pectoral-fin with gray rays and clear membranes (Fig. 6 B).

Females blue/green ground coloration with 7–8 brown bars; belly and breast light brown. Head with brown coloration and 2 faint blue/green interorbital bars; dark brown opercle spot with green highlights. Anal-fin spines black; rays gray; with 1–3 yellow ocelli. Pectoral fin with gray rays and clear membranes (Fig. 6 C).

Distribution. Tropheops kamtambo occurs at Chimwalani (S 13°46.240', E 34°57.770') and Luwala (S 13°45.975', E 34°56.255') reefs, and a very similar form has been reported (Konings 2007) from the area between the Mozambique-Malaŵi border and the Nsinje River, but no specimens were available to confirm their possible conspecificity.

Etymology. The name kamtambo is a noun in apposition and means “blue” in Chichewa (Nyanja). It refers to the blue coloration of breeding males.