Metriaclima glaucos, Ciccotto, Patrick J., Konings, Adrianus & Stauffer, Jay R., 2011

Ciccotto, Patrick J., Konings, Adrianus & Stauffer, Jay R., 2011, Descriptions of five new species in the genus Metriaclima (Teleostei: Cichlidae) from Lake Malaŵi, Africa, Zootaxa 2738, pp. 1-25 : 9-11

Metriaclima glaucos , new species

Fig. 4A –C; Table 3

Metriaclima sp. " aurora blue": Konings 2001: 155.

Holotype. PSU 4487, 69.2 mm SL; Mozambique: Lake Malaŵi: Cobwé, 12° 8.243' S, 34° 45.391' E; A.F. Konings & J.R. Stauffer, 18 Feb 2002.

Paratypes. PSU 4488, 16; UMBC 15, 1; AMNH 246003, 2; 53.0– 67.4 mm SL; data as for holotype.

Diagnosis. A moderately-sloped head and bicuspid teeth in the outer row of the jaws place this species in Metriaclima . The absence of a black submarginal band in the dorsal fin in conjunction with a yellow gular region and branchiostegal membranes, and the light-brown colored females that have yellow fin margins distinguish M. glaucos from other members of Metriaclima , except M. chrysomallos and M. benetos . There are generally fewer teeth in the outer row of the lower left jaw (mode 16, range 14–19) of M. glaucos compared to M. chrysomallos (mode 22, range 15–25) and more compared to M. benetos (mode 12, range 9–13). On the basis of color pattern, females of M. glaucos cannot reliably be distinguished from those of most other members of the Aurora group, but they differ from those of M. xanthos new species by a shorter lower jaw (mean 30.8, range 28.8–32.8 % HL vs. mean 35.4, range 34.6–36.7 % HL) and from those of M. aurora by 8–11 vertical bars below the dorsal fin vs. 6 in M. aurora .

Description. Morphometric and meristic data in Table 3 . Dorsal snout profile slightly concave to straight; mouth cleft slightly downward to horizontal; jaws isognathous. Teeth on dentary in 2-3 rows, on premaxilla in 2 or 3 rows; outer row teeth typically bicuspid anteriorly and unicuspid posteriorly, middle rows when present tricuspid, innermost row unicuspid; lower pharyngeal jaw with numerous slender teeth with teeth in posterior row slightly larger. Portion of upper dental arcade normally exposed when mouth closed. Tips of teeth in premaxilla and dentary in V-shaped line with anteriormost in upper and lower jaw furthest apart and not touching in closed mouth. Lateral scales ctenoid.

Breeding males light blue/gray laterally with 7 dark gray bars below dorsal fin and white belly. Head light blue/gray with preorbital, cheek, and operculum light blue; darker blue opercular spot; yellow gular region and brachiostegals. Dorsal fin blue with white lappets. Caudal-fin rays gray with white/blue membranes. Anal fin gray with 1–4 yellow ocelli. Pelvic fin with white leading edge, first ray gray and remainder clear. Pectoral fin clear.

Metriaclima glaucos

n=20

Lateral coloration of females gray dorsally and white ventrally. Head gray with gray cheeks, blue/gray operculum with green highlights, gray/black opercular spot, and white gular region. Dorsal fin gray with yellow/orange lappets. Caudal-fin rays gray with clear membranes and faint yellow/orange spots. Anal fin gray proximally and yellow distally without ocelli. Pelvic fin with white leading edge and black submarginal band, membranes yellow to clear. Pectoral fins clear.

Distribution. Metriaclima glaucos was collected at Cobwé, Mozambique, and is only known from the type locality ( Fig. 1 ).

Etymology. The specific epithet, glaucos , is Greek for bluish gray, in reference to the blue-gray body and fin coloration. It is treated as a noun in apposition.

Figures

FIGURE 1. Map of Lake MalaŴi showing the locations of species discussed throughout the text.

FIGURE 4. A. Metriaclima glaucos, holotype, PSU 4487, 69.2 mm SL; Mozambique: Lake MalaŴi: Cobwé. B. M. glaucos, male in habitat at Cobwé, Mozambique; approx. 65 mm SL; not preserved. C. M. glaucos, female in habitat at Cobwé, Mozambique; approx. 55 mm SL; not preserved.

Tables

TABLE 3. Morphometric and meristic values of Metriaclima glaucos from Cobwé. Mean and range include holotype.

	holotype	mean	range
Standard length, mm Head length, mm Percentage of standard length Head length	69.2 21.0 30.3	61.4 18.7 30.5	53.0–69.2 16.1–21.0 29.4–31.9
Snout to dorsal Snout to pelvic	32.7 37.4	33.4 38.2	31.7–34.6 35.9–40.4
Greatest body depth Caudal peduncle length Least caudal peduncle depth Dorsal-fin base length	31.9 14.6 10.9 64.4	32.8 14.2 11.0 61.9	31.8–34.0 12.5–15.5 9.9–12.3 59.8–64.4
Anterior dorsal to anterior anal Anterior dorsal to posterior anal	52.5 66.3	53.6 64.4	50.8–55.8 62.9–66.5
Posterior dorsal to anterior anal Posterior dorsal to posterior anal Anterior dorsal to pelvic-fin origin Posterior dorsal to pelvic-fin origin Percentage of head length Horizontal eye diameter	29.6 14.9 36.6 59.1 30.8	29.3 15.1 37.2 58.7 33.7	27.1–30.9 14.4–16.5 35.2–39.5 55.6–60.7 30.7–36.6
Vertical eye diameter Snout length Postorbital head length Preorbital depth	32.0 28.1 42.0 21.5	33.7 28.9 41.8 21.9	31.0–36.9 25.4–30.8 38.5–43.3 19.2–23.6
Lower-jaw length Cheek depth	29.3 25.0	30.8 23.8	28.8–32.8 21.4–26.7
Head depth Meristics Dorsal-fin spines Dorsal-fin rays Anal-fin spines Anal-fin rays	92.5 18 8 3 8	91.0 mode 18 9 3 8	86.5–95.9 range 17–19 8–10 3–3 7–8
Pelvic-fin rays Pectoral-fin rays Lateral line scales Pored scales posterior to lateral line Cheek scales Gill rakers on first ceratobranchial	5 14 30 1 6 11	5 14 30 2 6 11	4–5 14–15 29–32 0–2 4–7 10–11
Gill rakers on first epibranchial Teeth in outer row of left lower jaw Teeth rows on upper jaw Teeth rows on lower jaw	3 16 3 3	3 16 3 3	2–4 14–19 2–3 2–3