The type locality of this species is a cool, briskly flowing, upland stream less than 4 m wide and less than 1.5 m maximum depth; substratum was reported to consist of large, granitic boulders interspersed among deposits of coarse sand, mud, and leaf litter (Ref. 85844).
This species is distinguished from its congeners except D. chappuisi and D. stilicauda, by having the dorsolateral and ventrolateral vertebral processes extending through the dermis to form longitudinal bony ridges from the base of the adipose fin posteriorly to the caudal-fin base and from slightly posterior of the anal-fin origin to the caudal-fin base. The exposed processes are in the shape of longitudinal bars with slightly corrugated surfaces that together form an irregular longitudinal ridge. D. reidi differs from differs from D. chappuisi in having caudal-peduncle length 31% SL (vs. 22-29%); the posterior extent of the adpressed pelvic fin in specimens over 90 mm extending distinctly beyond anterior limit of the anal fin (vs. falling short of that point); the anterior extent of the exposed vertebral processes along the ventral surface of the body extending to the area lateral to the anal-fin base (vs. extending to slightly posterior of pelvic-fin origin); and, the pigmentation pattern of the dorsal surface of the unbranched rays of the pectoral and pelvic fins with a series of irregular dark spots against a lighter background (vs. uniformly pigmented). Doumea reidi differs from D. stilicauda in predorsal length 33% SL (vs. 27-30%); head length 18% SL (vs. 15-17%); caudal-peduncle length 31% SL (vs. 35-41%); and, caudal-peduncle depth 11.8 times in caudal-peduncle length (vs. 19.6-25.8 times) (Ref. 85844).
Holotype for Doumea reidi Catalog Number: USNM 337914 Collection: Smithsonian Institution, National Museum of Natural History, Department of Vertebrate Zoology, Division of Fishes Collector(s): G. Reid Year Collected: 1994 Locality: Mayo Malafa. a Stream Tributary On the Border Between Nigeria and Cameroon Which Drains To Cameroon (Evidently To the River Banyo and Then To the River Mbam, a Main Branch of the River Sanaga). Altitude ca 1525 m (5000 Ft), Nigeria, Africa
Holotype: Ferraris, C. J., et al. 17 Dec 2010. Copeia. 2010 (4): 709, Figs. 2, 3.