Lamprologus werneri Poll, 1959

SCHELLY, ROBERT C. & STIASSNY, MELANIE L. J., 2004, Revision of the Congo River Lamprologus Schilthuis, 1891 (Teleostei: Cichlidae), with Descriptions of Two New Species, American Museum Novitates 3451, pp. 1-40 : 18-22

Lamprologus werneri Poll, 1959

Figures 15–17 , Table 4, Plate 1d

Lamprologus werneri Poll, 1959 (part.): 108, pl. 19, figs. 2a–c (Type localities: MRAC 104003, MRAC 104004–104027, Regina Falls, near Kinsuka; MRAC 74905, Kalina, Léopoldville; MRAC 79195, Léopoldville, Stanley Pool; MRAC 118566–118567, Manianga (Stanley Pool); MRAC 118986–118988, Stanley Pool, rapids.

HOLOTYPE: MRAC 104003 , Regina Falls , near Kinsuka , 04 ° 20 ̍ S, 15 ° 13 ̍ E, 1/1/1955 – 12/31/1955, A. Werner .

PARATYPES: MRAC 74905, Kalina, Léopoldville, 04 ° 18 ̍ S, 15 ° 16 ̍ E, 1/1/1949 – 12/31/ 1949, J. Deheyn ; MRAC 79195, Léopoldville, Stanley Pool, 04 ° 18 ̍ S, 15 ° 18 ̍ E, 1/1/ 1952 – 12/31/1952, M.H. Pierret ; MRAC 104004–104027 (1 specimen c&s), Regina Falls , near Kinsuka, 04 ° 20 ̍ S, 15 ° 13 ̍ E, 1/1/ 1955 – 12/31/1955, A. Werner ; MRAC 118566–118567, Manianga (Stanley Pool), 04 ° 54 ̍ S, 14 ° 23 ̍ E, 8/17/1954, J. Mandeville ; MRAC 118986–118988, Stanley Pool, rapids, 04 ° 06 ̍ S, 15 ° 15 ̍ E // 04 ° 20 ̍ S, 15 ° 23 ̍ E, 4/ 1/1958 – 4/30/1958, P. Brichard .

ADDITIONAL MATERIAL EXAMINED: 220 specimens. Gombe or Ngombe, mainstream rapids of Congo River , about 20 km west of Kinshasa (4 ° 24 ̍ S, 15 ° 10 ̍ E) MCZ 50157 (N = 24), 6/23/1973, T.R. Roberts and D.J. Stewart. Kinshasa (Léopoldville) (04 ° 18 ̍ S, 15 ° 18 ̍ E) MRAC 44158–44177, 1/1/1935 – 12/31/1935, A. Tinant ; MRAC 47996, 1/1/ 1937 – 6/12/1937, A. Tinant ; MRAC 48004, 1/1/1937 – 6/12/1937, A. Tinant ; MRAC 55171–55185, 1/1/1937 – 12/31/1937, A. Tinant ; MRAC 73068.0087–0088, P. Brichard ; MRAC 79009.0970, 10/15/1961, P. Brichard. Kinsuka rapids, Kinshasa (04 ° 20 ̍ S, 15 ° 13 ̍ E) MRAC 177553, 1/1/1964 –12/31/ 64, P. Brichard ; MCZ 48002 (N = 4), 6/20/ 1971, T.R. Roberts. Manianga, Congo River rapids (04 ° 54 ̍ S, 14 ° 23 ̍ E) MRAC 98158– 98192, 8/12/1954, J. Mandeville ; MRAC 98193–98250, 9/24/1954, J. Mandeville. Regina falls , near Kinsuka (04 ° 20 ̍ S, 15 ° 13 ̍ E) MRAC 104003, 1/1/1955 – 12/31/1955, A. Werner ; BMNH 1977.1.11.25–29. Stanley Pool (04 ° 06 ̍ S, 15 ° 15 ̍ E // 04 ° 20 ̍ S, 15 ° 23 ̍ E) MRAC 98269–98317, 9/3/1954, J. Mandeville ; MRAC 118578, 8/10/1955, J. Mandeville. Rapids below Stanley Pool (4 ° 15 ̍ 2 ̎ S, 15 ° 25 ̍ 0 ̎ E) BMNH 1980.7.1.77.

DIFFERENTIAL DIAGNOSIS: Lamprologus werneri is unique among the Congo River congeners in having 15 (rather than 14 or rarely 13) precaudal vertebrae. Lamprologus werneri is further distinguished from L. lethops and L. symoensi by its regularly imbricating, large, uniformly sized flank scales (vs. irregularly sized flank scales), from L. mocquardi and L. tumbanus by the presence of a single supraneural (vs. absence of supraneurals), from L. congoensis , L. mocquardi , L. tumbanus , L. teugelsi , n. sp., and L. symoensi by a lower range for BD as a percentage of SL (17.3–20.3% vs., collectively, 20.6–28.9%), and from L. mocquardi by its uniformly dark pigment around the exposed margin of flank scales, giving appearance of chain mail. Lamprologus werneri is further distinguished from L. tigripictilis , n.sp., by presence of 5–6 rather than 9–10 dark vertical bars on flanks.

DESCRIPTION: Counts and measurements of 20 specimens, including seven paratypes from MRAC 104004–104027, are given in table 4. Lamprologus werneri , like L. lethops , is gracile with shallow body depth (17.3–20.3%, mean 18.7% SL). Greatest body depth at dorsal fin origin. Head length 29.1–32.9%, mean 30.6% SL. Dorsal head profile convex, rising at angle of about 40 °, gently curving to horizontal along dorsum; only slightly and indistinctly curving ventrally at caudal peduncle. Ventral body profile mostly straight except for very slight concavity at caudal peduncle. Nuccal hump absent in males and no obvious sexually dimorphic features present except that males achieve larger body size (largest male 91.5 mm SL, largest female 58.6 mm SL).

Fins: Dorsal fin XVIII–XX (mode XIX) 7–9 (mode 9). Anal fin V–VII (mode VI) 5– 7 (mode 6). Spines in both fins of gradually increasing length posteriorly. Filamentous extensions of soft dorsal and anal fins extending to about middle of caudal fin. Caudal fin large, rounded, and paddle­shaped, with 14 branched rays; often appears lanceshaped, subacuminate in preserved specimens. Pectoral fins short, not reaching vertical through anus. Pelvic fins reaching anus only in larger males; pelvic fins terminate anterior to anus in females and small males (pelvic fin length 19.0–24.4%, mean 21.6% SL). Second ray of pelvic fin longest in fin in both sexes.

Teeth: Jaws isognathous, but with lower lip sometimes protruding slightly; both outer and inner row teeth unicuspid and sharply pointed. Single series of 8 greatly enlarged, recurved, procumbent canines situated anteriorly; lateral­most canines considerably larger than inner canines. Inner teeth in 5–8 poorly defined rows of tightly packed, small, recurved caniniform teeth anteriorly. Tooth rows on each jaw reduced to single rows of medium sized caniniform teeth posteriorly, extending almost entire length of both dentary and premaxilla.

Gill Rakers: Slender, elongate, and nondenticulate. Gill rakers number 8–9 (mode 9) along hypobranchial and ceratobranchial of first arch; in most cases single raker occupies angle of arch. Epibranchial of first arch has 3–5 (mode 4) rakers.

Lower Pharyngeal Jaw: Wider than long, interdigitation along ventral suture absent or very slight. Most posterior row with 26–28 teeth. Median teeth enlarged, even slightly molariform; lateral teeth slender and beveled or bluntly hooked.

Scales: Flank scales ctenoid, of uniform size. Lateral line scales 34–37 (mode 35). Upper and lower branches of lateral line may or may not overlap. Cheek naked; opercle and subopercle partially scaled. Gradual transition to small scales on belly and above lateral line near dorsal fin origin, with small, embedded scales extending beyond dorsal fin origin onto nape. Dorsal and anal fins scaleless. Small scales occur over most of caudal fin.

Vertebrae: 31–33; 15 + 16 (1), 15 + 17 (17), 15 + 18 (2).

Additional Osteology (fig. 16): Infraorbital series comprised of broad, platelike lachrymal with 5–6 sensory canal openings and 1– 2 tubular infraorbitals adjacent to lachrymal. Dermosphenotic absent. Single supraneural present. Supraoccipital crest low and poorly developed, but extends anteriorly as low frontal ridge to median coronal pore (NLF0). Coronal pore borne on anterior elevation of frontal ridge in most specimens examined.

Coloration: Live coloration unknown. In alcohol, base body coloration yellowish brown. Five or six broad, dark vertical bars along flanks. Dorsal, anal, and sometimes caudal fin darkly pigmented, but lacking conspicuous pattern of spots or striations. Individual flank scales with dark pigment distributed uniformly around exposed posterior margin, creating intersecting rows of thin, oblique bands of pigment that present appearance of chain­link fence or chain mail. Adult males with iridescent spots in posterior field of most flank scales (adjacent to overlapping edge of previous scale).

DIET: Gut short and simple, with length about 55% of SL. Fish scales and disarticulated insect parts were recovered.

DISTRIBUTION (fig. 17): Known from Malebo Pool and the rapids immediately downstream, with one collection as far west as Manianga.

REMARKS: In their collections from the rapids below Kinshasa, Roberts and Stewart (1976) mentioned two color varieties among material they considered to be L. werneri . While a few small lots from their upstream collections are in fact L. werneri , most of their material is recognized herein as L. tigripictilis , n.sp.

Figures

Plate 1. (a) Lamprologus congoensis, MRAC 118140–53, male, 104 mm SL; (b) Lamprologus tumbanus, MRAC 100851–53, male, 51 mm SL; (c) Lamprologus mocquardi, AMNH 5897, male, 78 mm SL; (d) Lamprologus werneri, MRAC 98158–92, male, 56 mm SL.

Fig. 15. Lamprologus werneri, male, 123 mm TL, modified from Poll (1959).

Fig. 16. Lamprologus werneri, MRAC 104004–27: (a) neurocranium and first vertebra; (b) lachrymal and adjacent infraorbitals.

Fig. 17. Collection localities of Lamprologus werneri.