Metriaclima pambazuko, Stauffer Jr, Jay R., Black, Kristin & Konings, Adrianus F., 2013

Stauffer Jr, Jay R., Black, Kristin & Konings, Adrianus F., 2013, Descriptions of five new species of Metriaclima (Teleostei: Cichlidae) from Lake Malaŵi, Africa, Zootaxa 3647 (1), pp. 101-136 : 108-111

Metriaclima pambazuko , new species

Fig. 4 A–C

Metriaclima sp. ‘red top londo’ Konings 2007

Holotype. PSU 4900, adult male, 61.3 mm SL, 11° 49.552’ E 34°56.292’, Londo Bay, Lake Malaŵi, Mozambique, Africa, Konings & Stauffer Jr., 23 Feb 2006.

Paratypes. PSU 4901, 19, (51.9–73.2 mm SL), same data as holotype; PSU 4902, 19, 59.3–75.9 mm SL, Hongi, Lake Malaŵi, Tanzania, Konings & Stauffer Jr., 28 Jan 2004; PSU 4903, 18, AMNH 257793, 2, 61.8–74.7 mm SL, Lundo Island, Lake Malaŵi, Tanzania, Konings & Stauffer Jr., 29 Jan 2004.

Diagnosis. The presence of bicuspid teeth in the anterior portion of the outer row on both the upper and lower jaws and a moderately-sloped (37° in one uncatalogued specimen) ethmo-vomerine block with a swollen rostral tip place this species in Metriaclima . The yellow/orange dorsal fin of males in combination with distinct black bars on a blue ground color and the absence of a yellow chin distinguish this species from all other members of the genus except for M. emmiltos and M. pyrsonotos . The lateral bars of male M. pambazuko infiltrate the proximal portion of the dorsal fin and can form a solid band in males of the Lundo population, while the lateral bars of most males of M. emmiltos and M. pyrsonotos stop at the base of the dorsal fin. In some individuals of the latter species narrow bar extensions are visible in the dorsal fin but none have been encountered with black membranes in the soft-rayed part of the dorsal, which is another character of the color pattern of M. pambazuko . Also the anal fin of male M. pambazuko is darker and often black, while that of most male M. pyrsonotos and M. emmiltos is light blue.

Female M. pambazuko have a light brown to beige ground color while those of M. emmiltos and M. pyrsonotos are dark brown to blue-brown. M. pambazuko has more teeth in the outer row of the left lower jaw than M. emmiltos and M. pyrsonotos (13–23 vs. 8–12 and 4–10 resp.) and differs further from M. emmiltos by a larger distance between snout and pelvic-fin origin (35.3–44.2 % vs. 22.8–32.8 % SL).

Description. Morphometric and meristic data in Table 2 . Moderate compact species (mean BD 32.1% SL) with greatest body depth at about base of fifth dorsal spine. Dorsal body profile with gradual curve to caudal peduncle; ventral body profile slightly convex with similar, mirrored curve upward to caudal fin. Dorsal head profile straight between snout tip and interorbital, making about 45° angle with body axis, then rounding to dorsal fin origin; eye (mean 36.7% HL) almost twice depth preorbital and positioned in anterior half of head with posterior orbit margin on or slightly posterior of vertical median of head. Snout short with isognathous jaws; teeth on lower jaw in 2–4 rows with outer row bicuspid (some lateral teeth unicuspid) and inner rows tricuspid.

Dorsal fin with XVI or XVIII (mode XVII) spines and 8–10 (mode 9) soft rays. Anal fin with III spines and 7 or 8 (mode 8) soft rays. First 3 or 4 dorsal-fin spines gradually increasing in length posteriorly with first spine about ½ length of fourth spine; last 14 spines slightly increasing in length posteriorly with last spine longest; soft dorsal fin with rounded or subacuminate tip, third or fourth ray longest, about to middle of caudal fin in males and to base of caudal fin in females. Anal-fin spines progressively increasing in length posteriorly; fourth or fifth ray longest, length to almost middle of caudal fin in some males, to about base of caudal in females, length slightly shorter than dorsal fin. Caudal fin subtruncate to emarginate. Pelvic fin not reaching anal fin in females; length in males to first anal-fin rays. Pectoral fin rounded, paddle-shaped, short, reaching vertical through base of 10th or 11th dorsal-fin spine.

Flank scales large, ctenoid; abrupt difference to small scales on breast and belly; cheek with 3–6 rows of small scales. Dorsal and anal fins scaleless; tiny scales over proximal ¾ of caudal fin.

Live breeding males with blue ground coloration and 5–7 distinct black bars. Caudal peduncle blue/black; breast dark blue/black; belly gray/black. Head black with two blue interorbital bars; opercular spot gray-green/ black; throat black. Dorsal fin proximally blue/gray/black and distally yellow (Lundo Island population) to orange/ red (Londo Bay population); lateral bars extended onto proximal dorsal fin; dorsal fin with light-blue/white lappets in spinous portion. Caudal fin gray/black with wide, orange distal margin; proximal half of caudal-fin membranes black, distal half blue/gray. Anal fin black with 3–5 orange/yellow ocelli in rayed portion, with light-blue/white narrow margin. Pectoral fin with black/gray rays and clear membranes. Pelvic fin with narrow blue, white, or yellow leading edge; remainder black.

Females with gray-blue or light-brown ground coloration and 4–6 gray bars; lateral scales brown with blue center. Caudal peduncle beige/brown; belly and breast white/gray. Head brown/gray; opercle with blue/green highlights; black opercular spot; throat gray. Dorsal fin proximally gray and distally orange/brown. Caudal-fin rays gray; membranes clear. Anal fin gray without ocelli or with very small yellow/orange spots. Pectoral fins with gray rays and clear membranes. Pelvic fins with first two membranes black/gray, remainder clear.

Distribution. Metriaclima pambazuko is known from Lundo and Hongi islands in Tanzania and from Londo Bay in Mozambique ( Fig. 1).

Etymology. The name pambazuko , from Swahili, means dawn or sunrise to note the orange/red dorsal fin of males, alluding to the orange/red sky of daybreak.

Remarks. The coloration of M. pambazuko most closely resembles that of Cynotilapia zebroides (formerly known as C. afra , but this turned out to be a different species (see Tawil 2011)), but the presence of bicuspid teeth in the anterior portion of the outer row of both the upper and lower jaws distinguishes members of Metriaclima from those of Cynotilapia , a genus characterized by widely spaced, unicuspid teeth in the outer jaws. Cynotilapia zebroides and M. pambazuko are sympatric in Londo Bay, Mozambique, as well as at the two islands, Lundo and Hongi, in Tanzania.

Figures

FIGURE 4. Metriaclima pambazuko. A. Holotype, PSU 4900, adult male, 61.3 mm SL, Mozambique: Londo Bay; B. Male in breeding coloration (approx. 70 mm SL) at Hongi Island, Tanzania; C. Female (approx. 55 mm SL) in Londo Bay, Mozambique.

Tables

TABLE 2. Morphometric and meristic data for Metriaclima pambazuko from Londo Bay, Mozambique (PSU 4900 – 4901); Lundo Island, Tanzania (PSU 4903); and Hongi, Tanzania (PSU 4902). Ranges include the holotype.

Metriaclima pambazuko Standard length, mm Head length, mm Percent standard length	Holotype Mean 61.3 64.3 19.5 20.4	Londo Bay range 51.9–73.2 16.8–23.2	Hongi Island range 59.3–75.9 18.6–24.0	Lundo Island range 61.8–74.7 19.6–23.8
Head length	31.8 31.7	31.7	31.3	31.8
Body depth Snout to dorsal Snout to pelvic Dorsal-fin base length	31.2 32.1 33.3 33.3 38.3 38.0 59.4 60.2	30.5–33.5 31.5–35.7 35.3–39.1 58.8–62.7	28.9–33.0 32.2–35.1 35.9–39.8 58.3–62.6	30.6–35.6 30.4–36.2 36.1–44.2 56.8–63.7
Anterior dorsal to anterior anal Anterior dorsal to posterior anal	50.1 49.4 62.3 62.7	46.9–52.4 61.8–64.7	46.6–52.7 61.2–65.3	47.3–52.3 59.4–66.6
Posterior dorsal to anterior anal Posterior dorsal to posterior anal Posterior dorsal to ventral caudal Posterior anal to dorsal caudal Anterior dorsal to pelvic-fin origin Posterior dorsal to pelvic-fin origin	29.1 29.8 15.9 16.2 18.4 18.3 22.4 22.1 36.3 35.6 57.7 56.9	28.7–32.3 15.4–17.3 17.4–19.6 21.0–23.7 33.6–37.9 55.8–59.6	27.0–30.4 14.9–17.0 16.5–19.0 21.2–23.1 32.1–37.2 55.3–60.3	27.7–31.1 15.0–17.9 16.8–20.9 20.0–23.3 32.4–38.6 52.4–58.4
Caudal-peduncle length Least caudal-peduncle depth	14.6 15.0 10.9 11.2	14.2–17.4 10.5–12.0	13.0–16.3 10.2–11.5	12.8–17.2 10.3–12.4
Percent head length Snout length	31.4 33.9	30.1–36.0	31.8–35.8	30.8–37.9
Postorbital head length Horizontal eye diameter	39.3 40.0 37.0 36.7	38.4–43.3 35.3–40.8	38.3–42.1 33.0–39.9	37.3–41.7 31.2–37.9
Vertical eye diameter Head depth Preorbital depth Cheek depth	35.4 35.9 81.4 84.3 22.1 20.7 24.3 25.3	35.0–41.3 78.2–88.5 18.9–22.7 22.5–30.8	32.4–38.3 76.2–90.1 18.6–22.2 22.3–26.4	32.1–37.8 81.7–92.4 18.5–22.7 22.8–29.3
Lower-jaw length Meristics Dorsal-fin spines Dorsal-fin rays Anal-fin spines Anal-fin rays Pectoral-fin rays Pelvic-fin rays	36.9 37.2 Holotype Mode 16 17 10 9 3 3 8 8 14 14 5 5	34.4–40.2 Londo Bay 16–17 8–10 3 7–8 13–14 5	35.4–40.0 Hongi Island 16–18 8–10 3 7–8 14–15 5	36.1–40.1 Lundo Island 16–18 8–10 3 7–8 14–15 5
Lateral-line scales Pored scales post lateral line Cheek-scale rows Gillrakers 1st ceratobranchial	31 31 1 1 4 4 12 12	30–32 0–1 4–6 11–14	29–32 0–1 3–5 11–18	29–32 0–1 3–5 11–13
Gillrakers 1st epibranchial Teeth in outer series of left lower jaw	3 3 20 17	2–3 16–22	2–4 17–23	2–4 12–22
Tooth rows in upper jaw Tooth rows in lower jaw	3 3 3 3	3 3–4	3–4 3–4	2–4 2–3