Diagnosis: Labeotropheus chirangali differs from the robust Labeotropheus, except L. chlorosiglos and L. candipygia, due to its slender body, 26.6-33.2% of standard length vs. 35.2-41.6% in L. fuelleborni, 33.8-41.5% in L. aurantinfra, 35.2-41.5% in L. obscurus, 37.4-40.6% in L. alticodia and 34.3-42.0% in L. artatorostris; it has a slenderer body than L. chlorosiglos and L. candipygia, although its range of body depth partially overlaps with those of these species, 31.9-34.7% in L. chlorosiglos and 31.9-38.6% in L. candipygia (Ref. 128773). There are additional morphometric differences between L. chirangali and both L. chlorosiglos and L. candipygia, although some of the ranges overlap; it differs from both L. chlorosiglos and L. candipygia by shorter distances between the tip of the snout and the origin of the dorsal fin, 28.4-32.7% of standard length vs. 31.2-34.4% in L. chlorosiglos and 32.2-36.8% in L. candipygia, between the origin of the dorsal fin and the origin of the anal fin, 32.2-51.5% of standard length vs. 51.3-54.6% in L. chlorosiglos and 47.6-54.0% in L. candipygia, and between the origin of the dorsal fin and the attachment of the pelvic fins, 28.6-33.4% of standard length vs. 33.0-36.0% in L. chlorosiglos and 32.7-38.8% in L. candipygia; additionally, L. chirangali has a greater width between the opercular tabs, 15.1-17.8% of head length vs. 14.7-15.7% in L. chlorosiglos (Ref. 128773). Labeotropheus chirangali differs from the other slender-bodied Labeotropheus primarily due to the nuptial colouration of the males; male L. chirangali have a dark blue head, flank, and ventrum, and the scales in this region may have small ochreous-orange highlights; above this extensive dark blue patch, male L. chirangali have a bright sky-blue dorsum; this pigmentation extends onto the dorsal fin; the tips of the dorsal fin are yellow, as is the trailing edge of this fin; the anal fin and the pelvic fins are the same bright sky blue as the dorsal fin (Ref. 128773). Many of the morphometric and meristic values of L. chirangali overlap with those of the other slender Labeotropheus, although there are some distinctions; it differs from L. trewavasae due to a larger snout pad, 13.6-19.4% of head length vs. 10.3-14.2%, a wider lower jaw, 39.0-49.5% of head length vs. 34.7-43.9%, fewer rows of teeth in the lower jaw, 3-5 vs. 5-6, and more infraorbital neuromasts, 14-38 vs. 8-25; it differs from L. simoneae due to a greater rostral length, 39.2-47.6% of head length vs. 34.3-43.0%, a larger snout pad, 13.6-19.4% of head length vs. 9.5-15.9%, and fewer overlapping lateral line scales, 0-3 vs. 4-5; finally, L. chirangali differs from L. rubidorsalis due to a smaller distance between the tip of the snout and the origin of the dorsal fin, 28.4-32.7% of standard length vs. 31.4-35.0%, a greater distance between the insertion of the dorsal fin and the attachment of the pelvic fins, 54.1-58.8% of standard length vs. 49.5-55.1%, a smaller preorbital depth, 23.4-28.4% of head length vs. 26.6-32.9%, a larger snout pad, 13.6-19.4% of head length vs. 10.3-14.2%, and a greater number of ceratobranchial gill rakers, 7-10 vs. 5-8 (Ref. 128773).

Description: Body compressiform and slender; body depth 27.5-30.3% of standard length; flattened ovoid body shape, slightly deeper anteriorly than posteriorly; body wide, slightly cylindrical in transverse cross section (Ref. 128773). Scales on belly and anterior abdomen cycloid and tightly crowded; flank scales ctenoid; exposed portion of scale fan-shaped and approximately hexagonal; anterior lateral line overlapping posterior lateral line by 0-3 scales; anterior lateral line scales 23-25, posterior lateral line scales 11-15; dorso-lateral scale rows 7-11, pectoro-pelvic scale rows 9-13 (Ref. 128773). Dorsal fin of typical length for a Labeotropheus, 55.8-61.3% of standard length, 18-19 spines and 8-9 rays; origin of dorsal fin posterior to or overlapping opercular tab; dorsal-fin rays 3, 4, 5 long, reaching to hypural and beyond to caudal fin; anal fin angular anteriorly with slight rounding to membrane posteriorly; origin of anal fin opposite dorsal-fin spine 16; insertion of anal fin variable (anterior, opposite, or posterior) with respect to insertion of dorsal fin; anal-fin rays 3, 4, 5 reach past hypural in most males, these only reach to mid-caudal peduncle in females; caudal fin subtruncate; pectoral fin short, 19.3-24.7% of standard length, rounded, 13-14 rays; pelvic fin long, minimally reaching origin of anal fin and longer in the majority of specimens; pelvic-fin ray slightly produced and filamentous in males and females; pelvic-fin attachment opposite dorsal-fin spine 4 or 5 (Ref. 128773). Head short bu deep for a slender Labeotropheus; head profile moderately to strongly concave with prominent snout; snout of typical length but wide, 34.7-40.2% of head length, with protruding snout pad, 13.6-19.4% of head length; cheek with 3 scale rows; infraorbital pores 9-10, with 14-38 neuromasts among them; oral jaws long and wide; oral teeth tricuspid and closely set on both upper and lower jaws; 6-11 tricuspid teeth on lateral portion of left upper jaw (Ref. 128773). Gill rakers stout, triangular, and widely spaced; 7-10 ceratobranchial and 1-3 epibranchial gill rakers on first gill arch; all specimens with 1 raker between the cerato- and epibranchial rakers (Ref. 128773).

Colouration: Colouration of males: head and dorsum blue, varying among individuals from dark navy blue to lighter sky blue; ground colour of scales along flank and caudal peduncle blue, typically matching head and dorsum; i.e., males with sky blue head and dorsum have sky blue ground colour along flank; opercular tab black with metallic green sheen; 11 dark blue-black bars along flank and caudal peduncle; scales along flank and caudal peduncle typically with ochreous-orange dots near inserted portion, generally becoming more prominent on caudal peduncle; some individuals with ochreous orange on caudal peduncle only; dorsal fin blue, matching blue colour of dorsum, trailing edge and tips of dorsal fin ochreous orange; caudal fin blue suffused with orange, trailing edge ochreous orange; anal fin iridescent bluish white or bluish grey with 3-6 orange)yellow eggspots; posterior portion of pelvic fin very pale orange with white leading edge; prominent black stripe between leading edge and posterior pigment (Ref. 128773). Colouration of females: head and operculum brown; opercular tab black with faint green sheen; ground colour of flank and caudal peduncle light tan; 11 dark brown bars span flank and caudal peduncle; scales of flank and peduncle with small orange dot near insertion of scale; belly white; dorsal fin greyish brown or grey; caudal fin grey; thin orange trailing edge; spinous portion of anal fin white or grey, rayed portion greyish brown with orange trailing edge; 1-2 small orange-yellow eggspots present on rayed portion of anal fin; pelvic fin pale orange with white leading edge; thin black bar separates leading edge from posterior pigment (Ref. 128773). In preservative, males uniformly grey or brown with 11 dark bars spanning flank and caudal peduncle; females uniformly dark brown or grey with 11 faint vertical bars visible across flank and peduncle on some specimens (Ref. 128773).