Lamprologus, Schilthuis, 1891, Schilthuis, 1891

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 : 3-5

KEY TO SPECIES OF CONGO RIVER LAMPROLOGUS

1. 32 or more scales in lateral line; 30 or more vertebrae; head length 34.6% SL or less.. .................................. 2

– 29–31 scales in lateral line; 28–29 vertebrae; head length 34.6–37.0% SL; four sensory pore openings on the lachrymal; no interdigitation at LPJ suture (fig. 1a); supraneurals absent; relatively elevated supraoccipital crest continuous with frontal ridge extending to median coronal pore (fig. 2a)....................... Lamprologus tumbanus

2. Flank scales irregular in size (fig. 3a), obscuring parallel rows; scaleless patch on head extending caudally well beyond dorsal fin origin (fig. 4a); supraoccipital crest low, no frontal ridge extending to median coronal pore (fig. 2c)...................... 3

– Flank scales are of uniform size (fig. 3b), arranged in parallel rows; nape scaled to dorsal fin origin or beyond (fig. 4b,c); supraoccipital crest variable............... 4

3. Eyes greatly reduced and covered by thick skin; body depigmented; head dorsoventrally flattened; body depth 17.9% SL; 43–49 scales in lateral line; four sensory pore openings on the lachrymal; strongly interdigitating LPJ suture (fig. 1b); supraneural absent................. Lamprologus lethops

– Eyes not reduced; body pigmented; head not flattened; body depth 22.5–27.4% SL; 35– 42 scales in lateral line; five sensory pore openings on the lachrymal; no interdigitation at LPJ suture (fig. 1a); supraneural polymorphic............ Lamprologus symoensi

4. Dark pigment around entire caudal edge of each scale, giving chain­link fence appearance of intersecting bands on sides of body; scales extend anteriorly onto nape, or at least to dorsal fin origin (in L. teugelsi , n.sp.); single supraneural present or polymorphic....... 5

– Dark pigment restricted to dorsal half of caudal edge of each scale, giving appearance of oblique parallel bands; nape and region just below dorsal fin origin scaleless (fig. 4b); supraoccipital crest low, no frontal ridge extending to median coronal pore (fig. 2c); supraneural absent.................................... Lamprologus mocquardi

5. Pelvic fin extending posteriorly beyond anus; interdigitation at LPJ suture strong; low or elevated supraoccipital crest, continuous with frontal ridge extending to median coronal pore (fig. 2a,b)................. 6

– Pelvic fin very seldom (only in some large L. werneri males) or never reaching to anus; interdigitation at LPJ suture weak or absent (fig. 1a); low supraoccipital crest, continuous with frontal ridge extending to median coronal pore (fig. 2b)............... 7

6. 32–35 scales in lateral line; 14 precaudal, 30– 31 total vertebrae; BD 21.0–27.8% SL; elevated supraoccipital crest, (fig. 2a); 5–6 dark vertical bars on flanks; nuccal hump of fatty tissue forms in adult males...................... Lamprologus congoensis

– 35–37 scales in lateral line; 14 precaudal, 31– 33 total vertebrae; BD 17.1–24.4% SL; low supraoccipital crest, (fig. 2b); 9–10 dark vertical bars on flanks............................ Lamprologus tigripictilis , n.sp.

7. 34–37 scales in lateral line; 15 precaudal, 31– 33 total vertebrae; 12–15 total gill rakers on first gill arch; shallow bodied, BD 17.3– 20.3% SL......... Lamprologus werneri

– 32–34 scales in lateral line; 14 precaudal, 30– 32 total vertebrae; 8–11 total gill rakers on first gill arch; relatively deep­bodied, BD 21.9–28.6% SL.................................. Lamprologus teugelsi , n.sp.