Labrochromis mawe Mahulu & Seehausen, 2025, sp. nov.

Labrochromis mawe sp. nov. Haplochromis (Labrochromis) “stone”: Witte et al. 1992; Seehausen 1996; Seehausen and Bouton 1996; Seehausen et. al. 1997; Seehausen et al. 1999; Seehausen and van Alphen 1999. “ Haplochromis ” “stone”: Bouton et al. 1997. Type material. Holotype. • NMBE 1111880, male, 127.8 mm SL, Lake Victoria, Python Island, Mwanza Gulf, Tanzania, O. Selz, July 2010. Paratypes. • 35 Specimens 77.6–124.3 mm SL. All specimens are from Lake Victoria, Tanzania, Mwanza Gulf. • NMBE 1111864, 104.4 mm SL, NMBE 1111865, 91.3 mm SL, NMBE 1111866, 86.2 mm SL and NMBE 1111867, 81.6 mm SL, 4 females, Python Island, O. Seehausen, 01 st Dec 1993. • NMBE 1111868 116.0 mm SL, NMBE 1111869, 107.0 mm SL, NMBE 1111881, 112.7 mm SL and NMBE 1111878, 115.6 mm SL, 4 males, Python Island, O. Selz, 21 st June 2010. • NMBE 1111870, 90.5 mm SL and NMBE 1111872, 85.5 mm SL, 2 males, Python Island, O. Seehausen, 01 st Dec 1993. • NMBE 1111871, 116.7 mm SL and NMBE 1111873, 113.6 mm SL, 2 males, Python Island, O. Seehausen, 12 Nov. 1995. • NMBE 1111886, 120.0 mm SL, NMBE 1111887, 105.0 mm SL and NMBE 1111888, 106.1 mm SL, 3 females, Kissenda Island, O. Selz, 9 th June 2010. • NMBE 1111883, 111.5 mm SL and NMBE 1111897, 95.2 mm SL, 2 females, Kissenda Island, O. Selz, 9 th June 2010. • NMBE 1111891, 124.3 mm SL and NMBE 1111898, 108.3 mm SL, 2 males, Kissenda Island, O. Selz, 9 th June 2010. • NMBE 1111894, 115.0 mm SL, one male, Kissenda Island, O. Selz 7 th July 2010. • NMBE 1111895, 91.1 mm SL, one male, Kissenda Island, O. Selz 13 th July 2010. • NMBE 1111893, 106.1 mm SL, one male, Kissenda Island, O. Selz, 9 th June 2010. • NMBE 1111884, 99.1 mm SL, 1 female, Kissenda Island, O. Selz, 9 th June 2010. • NMBE 1111882, 115.7 mm SL, 1 male, Python Island, O. Selz 21 st June 2010. • NMBE 1111876, 115.2 mm SL, one male, Python Island, O. Selz, 17 th July 2010. • NMBE 1111877, 121.3 mm SL, one male, Python Island, O. Selz, 10 th July 2010. • NMBE 1111892, 82.8 mm SL, one male, Kissenda Island, O. Selz, 13 th July 2010. • NMBE 1111899, 96.0 mm SL, one male, Kissenda Island, O. Selz, 13 th July 2010. • NMBE 1111885, 99.2 mm SL, one female, Kissenda Island, O. Selz, 9 th June 2010. • NMBE 1111879, 111.0 mm SL, 1 male, Python, 10 th July 2010. • NMBE 1111874, 77.6 mm SL, one male, Python Island, O. Seehausen, 01 st Dec 1993. • NMBE 1111875, 87.8 mm SL, one male, Python Island, O. Selz, 10 th July 2010. • NMBE 1111890, 103.0 mm SL, 1 male, Kissenda Island, O. Selz, 13 th July 2010. • NMBE 1111896, 113.3 mm SL, one male, Kissenda Island, O. Selz, 1 st July 2010. • NMBE 1111889, 86.3 mm SL, one male, O. Selz, 14 th Nov. 2014. Description. Based on 36 specimens from Python and Kissenda islands including the holotype. Morphometric, meristic, and dentition characters are given in Table 1. Habitus. Large growing robust and deep-bodied species with a blunt and wide head, few wide bars and conspicuous red (in males) or brown (females) maculae in the soft part of dorsal fin. Dorsal head profile decurved to moderately concave with heavy head appearance. Snout slightly longer than broad, the mouth oblique, and the lips not thickened. Lateral snout outline with isognathous jaws and obtuse. Oral teeth. The teeth in the outer tooth row (Fig. 6 A, C) are unicuspid to weakly bicuspid, short, stout, distantly spaced, and implanted in an upright position. The inner series teeth are small, tricuspid, and are arranged in two rows anteriorly and anterolaterally in both jaws. Dental arcade and tooth band. Dental arcade rounded, not square shaped. Inner rows in both jaws are usually separated from the outer row by a moderate gap. Lower pharyngeal bone and dentition. The lower pharyngeal bone is strongly hypertrophied and stout with strongly enlarged molariform pharyngeal teeth (Fig. 6 B, D). Scales and squamation. The flank is entirely scaled with ctenoid scales. Scales are ovoid with vertical long axis, slender and slightly higher than wide. Operculum: scaled, scales cycloid; cheek: fully scaled, scales cycloid; caudal peduncle: scales moderately ctenoid, chest: entirely scaled; scales cycloid, somewhat deeply embedded, though not as deeply as in many other rock-dwelling cichlids such as Neochromis greenwoodi Seehausen & Bouton, 1998 and Mbipia mbipi Seehausen, Lippitsch & Bouton, 1998 and smaller than on flank. The size transition to the chest is gradual. The belly; is fully scaled, scales moderately ctenoid and not distinctly smaller than on flanks. Dorsal fin; scaleless, caudal fin; partially scaled with cycloid scales, anal fin; scaleless and pectoral fin scaleless. Coloration. Melanin pattern in both sexes: Males and females exhibit four to six broad vertical bars on their flanks (note that these can be hard to see in preserved specimens that have bleached slightly). Preserved specimens of both sexes exhibit a brownish coloration, with some individuals retaining their vertical bars (Fig. 3 A). Male nuptial coloration: Labrochromis mawe sp. nov. exhibits male nuptial color polymorphism and found in two distinct color morphs. One morph is entirely blue on the flanks, including the spinous part of the dorsal fin (Fig. 2 A, D). The other morph is reddish on the dorsal head surface, and red on operculum, anterior flanks and anterior dorsum with the remaining flanks appearing yellowish and greyish towards the posterior dorsum (Fig. 2 B, E; Seehausen and Bouton 1996; Seehausen et. al. 1999). Both morphs possess numerous characteristic red maculae in the soft part of the dorsal fin (Fig. 2). A nape band, nostril, forehead, supraorbital, intraorbital, hind-eye, preopercular and lachrymal stripes (Seehausen et al. 1999) may be visible or not depending on behavioral context; lower lip with a blue sheen. The caudal fin is translucent grey with red streaks and maculae, grading to solid red towards the edge, while the anal fin is proximally blue grey, distally faint red to solid red, with 2–6 orange egg dummies. In the red morph, the red color can extend into the spinous part of the dorsal fin. Females have yellowish-brown coloration. Distribution and ecology. Labrochromis mawe sp. nov. is known from the northern and central Mwanza Gulf in Lake Victoria, Tanzania. The species has been collected at Anchor, Kissenda, Kilimo, Python, Gabalema, Nyamatala and Hippo islands, Bwiru point, Karumo bay, Nyegezi rocks, Amranda point, Ngoma point, and Capri point (Fig. 1). The species inhabits moderately steep to steep slopes, with medium sized to very large rock boulders (Fig. 7). Subadult individuals are commonly caught in shallow inshore waters between rock boulders while adults inhabit greater depths. At the moderately steep Python Islands, they are found somewhat offshore at depths ranging from 3 meters to at least 8 meters. In very steeply sloping areas, such as Anchor Island and Nyegezi rocks, they are located inshore and at depths starting from 1.5 meters downwards (Seehausen 1996). Food. The diet of Labrochromis mawe sp. nov. is predominantly snails but insect larvae are eaten as well (Bouton et al. 1997; Seehausen 1996). Breeding. Like all Lake Victoria haplochromines, Labrochromis mawe sp. nov. is a female mouthbrooding care giver, wherein the female carries her eggs as well as the hatched larvae inside her mouth, providing them with a safe and nurturing environment until the larvae have resorbed the yolk sac and develop into independent, free-swimming juveniles. Spawning takes place throughout the year as far as we could ascertain. Mouthbrooding females are probably residing in the deeper part of the depth range and are not usually observed among shallow water boulders. Diagnosis and affinities. The nature of its pharyngeal dentition places Labrochromis mawe sp. nov. on the same level of structural modification as other described Labrochromis species (L. ishmaeli, L. humilior, L. pharyngomylus, L. teegelaari, L. mylergates, L. ptistes, L. mawepili sp. nov.). Labrochromis mawe sp. nov. differs from all other species except L. mawepili sp. nov. by eye size (smaller among compared species (21.3–25.9 vs 23–33), (Table 3), and habitat association. Specifically, L. mawe sp. nov. restricted to rocky substrates, unlike other species inhabiting sand and / or mud bottoms. L. mawe sp. nov. possess shorter head (31.7–34.9 % SL) compared to L. ptistes (34.2–37.6 % SL) and narrower interorbital width (25.0–30.2 % HL) compared to L. mylergates (26.0–33.0 % HL). L. mawe sp. nov. and L. mawepili sp. nov. share the habitat (rocky substrate) but L. mawe sp. nov. possess shorter and stouter teeth than L. mawepili sp. nov., wider interorbital width (24.0–31.8 % HL) as L. mawepili sp. nov. 23.3–27.9 (means 24.6–25.4) % HL, and broader lower jaw (22.7–34.9 % HL) as L. mawepili sp. nov. (20.2–27.5 % HL). L. mawe sp. nov. possesses 31 or 32 scales in the lateral line whereas L. mawepili sp. nov. 32 or 33 scales (Table 1). L. mawe sp. nov. exhibits broad vertical bars and no traces of lateral stripes while L. mawepili possesses broken midlateral and dorsolateral bands that are typically as distinct as or more distinct vertical bars. L. mawe sp. nov. exhibits color polymorphism with two color morphs (Seehausen and Bouton 1996): one morph is entirely blue on the flanks, including the spinous part of the dorsal fin. The other morph is reddish on the dorsal head surface, and red on operculum, anterior flanks and anterior dorsum with the remaining flanks yellow and greyish towards the posterior dorsum. Both morphs possess numerous characteristic red maculae on the soft part of the dorsal fin. The caudal fin is translucent grey with red streaks and maculae, grading to solid red towards the edges. The anal fin is proximally blue grey, distally faint red to solid red, with 2–6 orange egg dummies. Male nuptial coloration of L. mawepili sp. nov. is comparable to the blue morphy of L. mawe sp. nov. However, L. mawepili sp. nov. possesses 5–10 orange egg dummies in the anal fin. Male nuptial colouration of L. pharyngomylus is blue-grey overlying silver, with a distinct coppery sheen on the flanks. The dorsal fin is hyaline with pinkish lappets and a pink margin in the soft part. The anal fin is hyaline with yellow egg dummies, while the caudal fin is hyaline with a pink flush, most intense distally and on the ventral half of the fin (Greenwood 1981). The male nuptial coloration of L. humilior is dark silvery-grey with intense dusky blotches. A coppery flush extends over the cheek, operculum, and flank up to the origin of the anal fin. The anal and caudal fins are light red, with the color intensifying along the margins of both fins. The anal fin bears two or three yellow egg dummies (Greenwood 1981). Breeding males of L. teegelaari have a purplish-grey dorsum, with the purple color more intense anteriorly. The flanks, chest, and belly are bright red, while the caudal peduncle is yellow with a faint red overlay. Traces of 4–6 vertical bars are visible on the flanks. The dorsal head surface is grey with a red flush, and the rest of the head is bright red, except for the lower lip and branchiostegal membrane, which are white. The lachrymal bar is faint, and a dark bar is present on the vertical preopercular limb. The dorsal fin is light grey with a faint red flush, dark grey lappets, and red maculae on the soft part. The anal fin is light red anteriorly and greyish posteriorly, with egg dummies orange to reddish. A nape band, supraorbital, intraorbital, hind-eye, preopercular and lachrymal stripes faint; the caudal fin is hyaline, yellowish proximally, and has red maculae and streaks (Greenwood 1981). Etymology. Species name mawe from the Swahili word, for stone, referring to the habitat occupation of the species that is confined to rocks. Published as part of Mahulu, Anna & Seehausen, Ole, 2025, Two new cichlid species of the genus Labrochromis from rocky reefs of Lake Victoria, Tanzania (Perciformes, Cichlidae), pp. 117-137 in ZooKeys 1240 on pages 117-137, DOI: 10.3897/zookeys.1240.125699