Haplochromis quasimodo, Vranken & Steenberge & Heylen & Decru & Snoeks, 2022

Vranken, Nathan, Steenberge, Maarten Van, Heylen, Annelies, Decru, Eva & Snoeks, Jos, 2022, From a pair to a dozen: the piscivorous species of Haplochromis (Cichlidae) from the Lake Edward system, European Journal of Taxonomy 815, pp. 1-94 : 62-68

Haplochromis quasimodo sp. nov.

urn:lsid:zoobank.org:act:6AE722D9-3BF6-4DD5-8637-55B8400EDD11

Figs 1–2 , 35–37 ; Table 1

Differential diagnosis

Species with a piscivorous morphology; body rather deep [BD 33.5–41.7 (mean 37.4) % SL]; interorbital area narrow [IOW 40.5–48.7 (43.9) % HL]; outer oral teeth many and small [UOT 46–71 (median 58)]; dominant males light grey dorsally and blue-black ventrally.

Amongst piscivorous species from the Lake Edward system, H. quasimodo sp. nov. differs from H. latifrons sp. nov., H. mentatus , H. rex sp. nov., H. simba sp. nov., H. glaucus sp. nov., and H. aquila sp. nov. by the combination of small vs large outer oral teeth and a larger number of outer upper jaw teeth [UOT 46–71 (58) vs 22–47 (27–36)]; further from H. mentatus , H. rex sp. nov., H. simba sp. nov., H. glaucus sp. nov., and H. aquila sp. nov. by presence vs absence of a well-defined mid-lateral band.

It further differs from H. latifrons sp. nov. and H. mentatus by a deeper body [BD 33.5–41.7 (37.4) vs 27.2–32.3 (28.6–31.2) % SL]; further from H. rex sp. nov., H. simba sp. nov., and H. glaucus sp. nov. by a broader head [HW 42.0–48.1 (45.3) vs 36.8–41.6 (39.2–40.8) % HL].

It differs from H. kimondo sp. nov. and H. squamipinnis by a narrower interorbital area [IOW 40.5– 48.7 (43.9) vs 48.6–58.5 (51.9–52.8) % HW]; further from H. kimondo sp. nov. by the combination of a rhomboid vs pyriform body, a concave to weakly convex vs convex dorsal outline of head, a gentler sloping snout (30–40° vs 40–50°), and dominant males light grey dorsally and blue-black vs grey dorsally and yellow ventrally; further from H. squamipinnis by a gentler gape inclination (20–35° vs 30–45°), a shorter lower jaw [LJL 44.2–49.6 (47.1) vs 47.8–58.6 (52.5) % HL], mostly absence vs presence of minute scales on proximal part of dorsal fin (rarely few rows of 1–4 scales present on dorsal fin in H. quasimodo sp. nov.), and dominant males light grey dorsally and blue-black ventrally vs slate blue.

It differs from H. falcatus sp. nov. by the combination of a shorter head [HL 33.9–37.2 (35.5) vs 36.6– 39.6 (38.2) % SL], a longer pelvic fin [VL 26.2–33.7 (29.4) vs 21.6–25.7 (23.5) % SL], weakly recurved vs strongly recurved outer oral teeth, and dominant males light grey dorsally and blue-black ventrally vs olive-green with an orange-red anterior part of flank.

It differs from H. curvidens sp. nov. and H. pardus sp. nov. by a deeper cheek [ChD 24.8–32.9 (exceptionally 23.7 in one specimen) (mean 27.5) vs 20.8–24.9 (22.5–23.2) % HL]; further from H. curvidens sp. nov. by a deeper body [BD 33.5–41.7 (37.4) vs 29.0–32.0 (30.8) % SL] and presence vs absence of a well-defined mid-lateral band; further from H. pardus sp. nov. by a larger number of caudal peduncle scales (CPS 17–20, rarely 16 vs 16, rarely 17), a larger adult size (max. 165 vs 96 mm SL), and colour pattern of small specimens (<100 mm SL) light coloured vs speckled to uniformly black.

Small specimens (<90 mm SL) resemble H. schubotziellus Greenwood, 1973 in overall habitus and colour pattern. It differs from the holotype of H. schubotziellus (NHMUK 1972.6.2.351; ♀, 75.0 mm SL; Lake George, Kankurunga Island) by a smaller eye [ED 26.2–31.8 (29.2) vs 33.7% HL], a longer lower jaw [LJL 44.2–49.6 (47.1) vs 42.6% HL], a deeper cheek [ChD 23.7–32.9 (27.5) vs 24.0% HL], outer oral teeth with no to a small minor cusp vs a well-defined minor cusp, and inner oral teeth set in 1–2 weakly defined rows vs 2 well-defined rows in both jaws.

Etymology

Specific name from Quasimodo, hunchbacked character in Victor Hugo’s novel ‘Notre-Dame de Paris’ (1831); referring to rather shallow head and deep and rhomboid bodies of large specimens.

Material examined

Holotype UGANDA • ♂, 120.4 mm SL; Lake Edward; 0°21’31.7″ S, 29°43’17.7″ E; deep catch, open water ± 30 m deep; 1 Feb. 2018; HIPE3 exped. leg.; RMCA 2018.008.P.0336 .

Paratypes DEMOCRATIC REPUBLIC OF THE CONGO • 1 ♀, 147.8 mm SL; “Lac Edouard: 2–3 km ± 500 m au large à l’Ouest de Kiavinionge” [Lake Edward: 2–3 km ± 500 m offshore west of Kiavinionge ]; 0°11′39″ S, 29°32′31″ E (inferred); 1 Jun. 1953; KEA exped. leg.; IRSNB 13480 • 1 ♀, 164.9 mm SL; “Lac Edouard: Kaniatzi (partie N. du lac)” [Lake Edward: Kaniatzi (northern part of Lake)]; 1 Jun. 1953; KEA exped. leg.; IRSNB 13481 • 1 ♂, 147.6 mm SL; “Lac Edouard: 2–3 km à l’Ouest de Kiavinionge” [Lake Edward: 2–3 km west of Kiavinionge ]; 0°11′39″ S, 29°32′31″ E (inferred); 1 Jun. 1953; KEA exped. leg.; IRSNB 13485 • 2 ♀♀, 141.5 mm SL; “Lac Edouard: Vitshumbi (au Nord)” [Lake Edward: north of Vitshumbi ]; 0°40′50.6″ S, 29°23′22.6″ E (inferred); 02 Jul. 1953; KEA exped. leg.; IRSNB 13488 .

UGANDA – Lake Edward • 2 ♀♀, 2 ♂♂, 92.7–114.3 mm SL; Katoko breeding ground, soft substrate offshore of Katwe ; 0°09′43.2″ S, 29°53′16.8″ E; 20 Oct. 2016; HIPE1 exped. leg.; RMCA 2016.035.P.0208 to 0211 • 2 ♀♀, 83.4, 93.1 mm SL; Mukutu Kihinga, rocky offshore of Mweya ; 0°11′31.2″ S, 29°52′26.4″ E; 23 Oct. 2016; HIPE1 exped. leg.; RMCA 2016.035.P.0213 to 0214 • 1 ♂, 78.9 mm SL; Mukutu Kihinga, rocky offshore of Mweya ; 0°11′31.2″ S, 29°52′26.4″ E; 23 Oct. 2016; HIPE1 exped. leg.; RMCA 2016.035.P.0212 • 3 ♀♀, 79.4–110.1 mm SL; Rwenshama , rocky shore; 0°24′05.7″ S, 29°46′35.1″ E; 26 Mar. 2017; HIPE2 exped. leg.; RMCA 2017.006.P.0349 to 0351 • 1 ♂, 89.1 mm SL; islands near Katwe ; 0°10′04.9″ S, 29°52′27.4″ E; 18 Jan. 2018; HIPE3 exped. leg.; RMCA 2018.008.P.0334 • 1 ♀, 130.7 mm SL; 0°24′16.0″ S, 29°46′24.8″ E; 24 Jan. 2018; HIPE3 exped. leg.; bought at Rwenshama landing site; RMCA 2018.008.P.0335 • 1 ♀, 148.8 mm SL; 0°21′31.7″ S, 29°43′17.7″ E; 1 Feb. 2018; HIPE3 exped. leg.; deep catch, open water ± 30 m deep; RMCA 2018.008.P.0339 • 1 ♀, 1 ♂, 117.9, 126.2 mm SL; 0°21′31.7″ S, 29°43′17.7″ E; 1 Feb. 2018; HIPE3 exped. leg.; deep catch, open water ± 30 m deep; RMCA 2018.008.P.0337 to 0338 .

Description

Based on 21 specimens (78.9–164.9 mm SL); body average in depth in comparison to generalised H. elegans (but deep for a piscivorous species; Table 1 ) and rhomboid ( Fig. 35 ). Head average in width and with a concave to weakly convex dorsal outline; eye small; interorbital area very narrow; cheek and lacrimal deep; lacrimal somewhat convex and hereby protrudes somewhat laterally. Snout average in length, acute, and slopes gently at 30–40°; premaxillary pedicel long and prominent. Jaws isognathous, long, slim, narrow, and rounded in dorsal view; gape large and slopes gently at 20–35°; maxilla extends to between verticals through anterior margins of orbit and pupil. Lower jaw shallow and with a straight ventral outline in lateral view, mental prominence absent or weakly developed, and lower jaw side nearly flat with an inclination of 15–25° to horizontal in anterior view. Upper jaw not expanded. Lips and oral mucosa thin. Neurocranium average in depth, ethmo-vomerine block decurved to horizontally inclined, preorbital region shallow (21–24% NL), orbital region average in depth (30–32% NL), and supraoccipital crest deep and pyramidical or weakly wedge-shaped ( Fig. 36b ).

Outer oral teeth numerous and very small. Necks stout, conical, and straight; crowns weakly recurved, unicuspid in large specimens (> 80 mm SL), anteriorly unicuspid and posteriorly mostly bi-, weakly bi-, and weakly tricuspid in small specimens (<80 mm SL), all acutely pointed. Dental arcades rounded. Outer teeth closely and regularly set with neck-distances of ½–1 neck-width. In upper jaw, 1–3 posteriormost teeth slightly enlarged. Inner teeth small, straight, an admixture of acutely pointed unicuspids and weakly tricuspids. Tooth bands very slender crescent-shaped with 1–2 rows of inner teeth, and narrow posteriorly until only outer row remains past ⅔ length of tooth band. Inner teeth closely and regularly set on 1–3/2 outer neck-widths from outer row; implantation mostly recumbent; size uniform throughout tooth band.

Lower pharyngeal bone average in length, triangular, slim, and shallow over whole length ( Fig. 37 ). Pharyngeal teeth relatively large and slender; major cusps acutely pointed; cusp gaps nearly straight; minor cusps and cusp protuberances mostly absent. Teeth in two median longitudinal rows equal in size and form to lateral teeth, 11–13 in each row. Posterior transverse row with 20–21 teeth, implanted erectly with a lateral inclination; major cusps nearly straight, bluntly pointed, and laterally compressed; minor cusps mostly present.

Chest scales small; transition to larger flank scales gradual. Minute scales on proximal half of caudal fin.

Caudal fin emarginate; dorsal and anal fins reach to between verticals through caudal-fin base and two scales posterior to this vertical. In about half of all specimens (10 of 21 type specimens), some minute, ellipsoid scales present on basal part of membrane of anal fin; between some pairs of fin rays, up to two rows of 1–5 scales extend from body onto fin; scales very variable in distribution and invisible to naked eye ( Fig. 35 ). Dorsal fin rarely with a few isolated rows of 1–4 minute scales (in 3 of 21 type specimens). Pectoral fin long and reaches to between first anal-fin spine and second anal fin branched ray; pelvic fin reaches to between first and second anal-fin spine in females, to second anal fin branched ray in males; first branched pelvic-fin ray elongated in all specimens.

All gill rakers in outer row of first gill arch short, relatively stout, and mostly simple, but sometimes anvil-shaped or weakly bifid.

Colouration in life

Dominant males: body and dorsal part of head light grey with faint yellow sheen; ventral half of body blue-black; belly and chest black; cheek, lower jaw, and lips white; snout dusky; eye with (dark) grey outer ring and silver inner ring ( Fig. 36c ). Flank with a well-defined mid-lateral band, an interrupted dorsal-lateral band, and 5–6 vertical stripes; lacrimal and vertical preopercular stripes well-defined; posterior margin of operculum black. Pectoral fin hyaline; pelvic fin black; dorsal fin dusky and with black lappets, base, and posterior part; anal fin black and with 2–7 very large egg spots (i.e., three times distance between rays) with dusky rings; caudal fin dusky and with black base, hyaline distal part, and maculated dorsal part.

Females and juveniles: body and head uniformly white, except for light grey dorsum and dorsal part of head and a dusky snout; eye with (dark) grey outer ring and silver inner ring ( Fig. 36d ). Flank with faint to well-defined mid-lateral and interrupted dorsal-lateral bands. Pectoral and dorsal fins hyaline; dorsal fin with black lappets and dusky base and distal part; anal and caudal fins yellow; anal fin with 3–5 spots resembling egg spots; caudal fin with a dusky base and a dusky and maculated dorsal part.

Preserved colouration

Body and operculum with yellowish dorsal part, white ventral part; transition gradual; in dominant males, ventral part of body overlain black ( Fig. 36a ). Flank with mostly mid-lateral and interrupted dorsal-lateral bands; in dominant males, with 5–6 vertical stripes. Cheek yellowish, snout dusky, and lower jaw whitish. Nostril and interorbital stripes and nape band faint in all specimens; lacrimal stripe faint in females, broad and well-defined in males; vertical preopercular stripes well-defined in males. Pectoral fin hyaline; pelvic and anal fins yellowish in females and black in males; anal fin with 2–7 large egg-spots in males. Caudal and dorsal fins dusky and dorsal fin with black lappets; in males, base of caudal fin and posterior part of dorsal fin black.

Distribution and ecology

Endemic to Lake Edward system; found in offshore, benthic areas in shallow and deep waters. Based on its morphology, most probably a piscivorous species.

Figures

Fig. 1. The Lake Edward system, consisting of Lakes Edward and George that are connected through the Kazinga Channel. The catch localities of all examined specimens are indicated: Haplochromis sp. ‘latifrons’ (), H. mentatus Regan, 1925 (), H. sp. ‘rex’ (), H. sp. ‘simba’ (▼), H. sp. ‘glaucus’ (), H. sp. ‘aquila’ (), H. sp. ‘kimondo’ (●), H. sp. ‘falcatus’ (), H. sp. ‘curvidens’ (), H. sp. ‘pardus’ (), H. sp. ‘quasimodo’ (▲), and H. squamipinnis Regan, 1921 (█). The type localities of H. mentatus and H. squamipinnis are not shown as the exact locations are unknown.

Fig. 2. a. Differences in total number of outer teeth and premaxillary dentition between the macro- and microdontic groups of piscivores from the Lake Edward system.b. Schematic presentation of the dominant male colour patterns in life, in the various groups studied. For H. sp. ‘latifrons’ the female and for H. sp. ‘curvidens’ the non-dominant colour patterns are shown, as those of dominant males are unknown.

Fig. 35. Haplochromis quasimodo sp. nov., holotype, ♂, 120.4 mm SL (RMCA 2018.008.P.0336). Drawn by N. Vranken.

Fig. 36.Haplochromis quasimodosp. nov. a. Photograph of preservedholotype (RMCA 2018.008.P.0336; 120.4 mm SL). b. X-ray image of holotype. c–d. Photographs of freshly caught specimens. c. Dominant male (RMCA 2018.008.P(HP3072); 123.7 mm SL). d. Female (RMCA 2018.008.P(HP3064); 116.6 mm SL) to illustrate the live colour patterns. The contrast was slightly enhanced.

Fig. 37. Haplochromis quasimodo sp. nov. (RMCA 2018.008.P.0337; 126.2 mm SL). a. Dorsal view of the lower pharyngeal jaw. b. Lateral view of the lower pharyngeal jaw.