New Species of Hemigrammocharax (Characiformes: Distichodontidae) from the Northwestern Congo River Basin Fernando C. Jerep1 and Richard P. Vari1 Copeia 2013, No. 1, 31–37 New Species of Hemigrammocharax (Characiformes: Distichodontidae) from the Northwestern Congo River Basin Fernando C. Jerep1 and Richard P. Vari1 Hemigrammocharax rubensteini is described from the northwestern Congo River basin in the Lékoli River of the Likouala River system, Republic of the Congo. The species differs from congeners in the combination of pigmentation pattern, meristics, and position of the dorsal fin. The presence of a well-developed pseudotympanum, a feature not previously reported in the Distichodontidae, is reported for H. rubensteini and other members of Hemigrammocharax and Nannocharax. S PECIES of the genus Hemigrammocharax inhabit the streams and rivers of major portions of sub-Saharan Africa including the Congo, Cunene, Okavango, and Zambezi river basins (Poll, 1973; Daget and Gosse, 1984). Hemigrammocharax was proposed by Pellegrin (1923) to host Nannocharax ocellicauda, a species which although sharing the other diagnostic features of the species then assigned to Nannocharax, nonetheless lacked poring of the lateral line along the posterior portion of the body contra the completely pored lateral line in the other species of Nannocharax. As now defined, Hemigrammocharax consists of nine species diagnosed among the genera of the Distichodontidae by the presence of a single row of teeth on the dentary and premaxilla and incomplete poring of the lateral line. Hemigrammocharax is hypothesized to form a natural lineage with Nannocharax inside the family Distichodontidae based on the common possession in those genera of a series of characters involving multiple body systems (Vari, 1979:331); however, the monophyly of Hemigrammocharax has yet to be assessed and indeed has been questioned (Vari and Géry, 1981:1082). We describe a new species from the Likouala River basin, a tributary on the Congo River in the northwestern portion of the basin that conforms to the present concept of Hemigrammocharax and is assigned to that genus pending the results of ongoing phylogenetic analyses. MATERIALS AND METHODS Measurements and counts conform to those used by Vari and Ferraris (2004) and Dunz and Schliewen (2009). Measurements were taken point-to-point on the left side of the specimens under a microscope using a digital caliper with a precision of 0.1 mm. Body measurements are given as a percentage of the standard length (SL), except for subunits of the head which are presented as percentages of the head length (HL). In the description, the frequency of a value is indicated by the number of specimens in parentheses. The value for the holotype is presented in square brackets. Details of dentition, infraorbitals, gill rakers, supraneurals, and scale ctenii were taken from two cleared-and-stained specimens prepared according to Taylor and Van Dyke (1985). Vertebral count was taken from cleared-and-stained specimens and radiographs and includes the four vertebrae of the Weberian apparatus and the terminal centrum. Presence of the pseudotympanum was verified on alcoholpreserved material by incident and/or transmitted light 1 under a microscope with pseudotympanum morphology assessed by removal of the overlying skin and adipose tissue of an alcohol-preserved specimen. Muscular nomenclature follows Winterbottom (1974). Museum abbreviations follow the listing in http://www.asih.org/node/204. Hemigrammocharax rubensteini, new species Figure 1, Table 1 Holotype.—CU 89502, 23.6 mm SL, Republic of the Congo, Cuvette-Ouest, Likouala River Drainage, Lékoli River at Mboko dock, Odzala National Park, 0u37930N, 14u549270E, J. P. Friel, S. Lavoué, J. P. Sullivan, 6 August 2002. Paratypes.—All Republic of the Congo, Cuvette-Ouest: CU 97248, 8, 6 alc, 20.0–25.8 mm SL, 2 CS, 21.3–21.9 mm SL; AMNH 255311, 2, 20.1–21.9 mm SL; MRAC B2-05-P-1-2, 2, 20.0–22.8 mm SL; USNM 405306, 2, 20.3–22.1 mm SL, captured with holotype. CU 89498, 6, 20.8–24.6 mm SL, Likouala River drainage, small creek draining into Mambili River, Odzala National Park, J. P. Friel, S. Lavoué, J. P. Sullivan, 27 August 2002. CU 89499, 2, 19.7–19.8 mm SL, Likouala River drainage, Lékoli River, Odzala National Park, 0u369510N, 14u569110E, J. P. Friel, S. Lavoué, J. P. Sullivan, 8 August 2002. CU 89500, 4, 19.8–25.4 mm SL, Likouala River drainage, Pandaka River, Odzala National Park, 0u379260N, 14u559350E, J. P. Friel, S. Lavoué, J. P. Sullivan, 12 August 2002. CU 89501, 6, 20.1–24.1 mm SL, Likouala River Drainage, Lékoli River at Mboko dock, Odzala National Park, 0u37930N, 14u549270E, J. P. Friel, S. Lavoué, J. P. Sullivan, 13 August 2002. CU 97249, 1 (meristics and morphometrics not taken), 18.2 mm SL, Likouala River Drainage, Lékoli River, Odzala National Park, 0u369510N, 14u569110E, J. P. Friel, S. Lavoué, J. P. Sullivan, 8 August 2002. Diagnosis.—Hemigrammocharax rubensteini is distinguished from all congeners, except H. lineostriatus, by the presence of a dark, typically continuous, longitudinal band extending from the posterodorsal margin of the opercle to the dark spot overlying the caudal peduncle (versus a body pigmentation pattern consisting of several vertical bars in H. angolensis, H. machadoi, H. minutus, H. monardi, H. multifasciatus, and H. wittei or lacking a dark longitudinal band in H. ocellicauda and H. uniocellatus). In specimens of H. rubensteini in which the longitudinal band is variably Division of Fishes, Department of Vertebrate Zoology, National Museum of Natural History, Smithsonian Institution, Washington, D.C.; E-mail: (FCJ) fjerep@gmail.com; and (RPV) varir@si.edu. Send reprint requests to RPV. Submitted: 8 May 2012. Accepted: 24 September 2012. Associate Editor: D. Buth. F 2013 by the American Society of Ichthyologists and Herpetologists DOI: 10.1643/CI-12-059 32 Copeia 2013, No. 1 Fig. 1. Hemigrammocharax rubensteini, CU 89502, 23.6 mm SL, holotype; Africa, Republic of the Congo, Cuvette-Ouest, Likouala River drainage, Lékoli River at Mboko dock, Odzala National Park. interrupted, the pigmentation pattern somewhat resembles that of H. lineostriatus, in which the continuous dark longitudinal line has several short vertical bars along its length. Hemigrammocharax rubensteini differs from H. lineostriatus in having the dorsal-fin origin located anterior to the vertical through the pelvic-fin origin (versus the dorsalfin origin located posterior to the vertical through the pelvic-fin insertion), 18 to 30 perforated scales along the lateral line (versus 6 to 9), and 12 to 14 branched dorsal-fin rays (versus 9 to 11). Hemigrammocharax rubensteini has a variably discontinuous lateral line which in some instances has only a few unpored scales and thus approximates the completely pored lateral line characteristic of the species of Nannocharax. The new species differs from the member of that genus with a continuous dark midlateral longitudinal band both in the incompletely pored lateral line (versus completely pored) and the lower number of total scales along that series (35–38 versus 39 or greater in N. ansorgii, N. latifasciatus, N. lineomaculatus, N. parvus, and N. usongo). Description.—Morphometric data presented in Table 1. Small body size with maximum length 25.8 mm SL. Body slightly Table 1. Morphometrics of Hemigrammocharax rubensteini, New Species. Range, mean, and standard deviation (SD) include values for the holotype. Holotype n Range Mean SD Standard length 23.6 33 19.7–25.8 21.7 1.7 Percentage of SL Head length Predorsal length Prepectoral length Prepelvic length Preanal length Head width Body width Head depth Body depth Dorsal-fin length Pectoral-fin length Pelvic-fin length Anal-fin length Caudal-peduncle length Caudal-peduncle depth 32.3 48.5 31.8 51.4 78.2 16.3 13.1 21.7 29.3 24.9 17.9 19.4 15.1 14.1 12.3 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 30.0–34.4 47.5–51.4 30.1–34.9 49.1–54.3 76.1–80.5 14.4–22.2 9.9–14.6 20.9–23.3 24.5–29.5 16.4–29.4 13.6–18.6 18.0–21.5 12.3–17.9 11.2–15.3 11.8–13.1 32.1 49.6 32.5 52.1 78.4 15.6 12.2 22.0 27.2 22.0 16.0 19.6 14.6 13.4 12.6 1.0 0.9 1.0 1.0 1.1 1.6 1.1 0.6 1.1 2.9 1.3 1.0 1.2 0.9 0.3 Percentage of HL Eye horizontal diameter Snout length Upper-jaw length Interorbital width 40.0 26.6 18.7 23.9 33 33 33 33 34.3–41.6 24.0–32.0 17.8–23.4 20.5–25.8 38.3 28.5 19.9 23.7 1.7 1.8 1.2 1.2 Jerep and Vari—Hemigrammocharax from Congo elongated and laterally compressed (Fig. 1). Dorsal profile convex from tip of snout to vertical situated slightly anterior to anterior nares, straight to slightly convex from that point to tip of supraoccipital spine. Dorsal profile convex from tip of supraoccipital spine to dorsal-fin origin; straight to slightly convex along dorsal-fin base; straight from insertion of last dorsal-fin ray to posterior terminus of adipose-fin base; and straight to slightly concave along caudal peduncle. Ventral profile of head convex along anterior portion of dentary; slightly convex from that point to isthmus. Ventral profile of body slightly convex from isthmus to pelvic-fin insertion; straight to slightly concave from pelvic-fin insertion to vertical situated anterior to urogenital papillae; concave from that point to anal-fin origin; slightly convex to straight along anal-fin base; and straight to slightly concave along caudal peduncle. Ventral surface of body flattened between pelvic-fin insertions. Head pointed in lateral profile with snout rounded. Mouth subterminal; located posteroventral of tip of snout. Premaxilla bearing one tooth row consisting of 6 elongate, bicuspid, slightly distally expanded teeth. Teeth on premaxilla gradually decreasing in size posteriorly; posteriormost tooth approximately one-half size of tooth proximate to symphysis. Contralateral premaxillae attached medially through syndesmotic articulation. Dentary bearing one tooth row consisting of 6 elongate, bicuspid, slightly distally expanded teeth gradually decreasing in size posteriorly, with posteriormost tooth approximately one-half size of symphyseal tooth. Contralateral dentaries medially attached through syndesmotic immovable articulation. Dentary movably articulated posteriorly with anterodorsal region of anguloarticular and lacking laterosensory canal segment. Maxilla toothless, flat and expanded posteriorly. Ventral margin of maxilla straight and posterior border rounded. Maxilla extending posteriorly to vertical through anterior margin of anterior nares. Posterior portion of maxilla lying medial to anterior portion of first infraorbital when mouth closed. Anterior naris rounded, separated posteriorly from triangular posterior naris by skin flap. Eye laterally situated with pupil ovoid and slightly extended anteriorly. Infraorbital series with infraorbitals 1 to 3 well developed, infraorbitals 4 and 5 absent, and infraorbital 6 limited to ossified laterosensory canal segment. Dorsal-fin origin located slightly anterior to middle of SL and anterior to vertical through pelvic-fin insertion. Distal profile of fin straight to slightly convex. Most branched dorsal-fin rays of same length other than few posteriormost rays progressively decreasing in size. Unbranched dorsal-fin rays ii (1), iii (17), iv (14), or v (1); branched rays 12(1), 13 (11), or 14 (21) [iii,14]. Pectoral fin pointed in profile. Tip of pectoral fin falling short of pelvic-fin insertion. Unbranched pectoral-fin rays i (33); branched rays 8 (18), 9 (14), or 10 (1) [i,9]. Distal profile of pelvic fin straight to slightly convex. Tip of fin falling short of anal fin. Pelvic-fin rays i,7,i (33) [i,7,i]. Adipose fin well developed with origin situated along vertical slightly anterior to base of last anal-fin ray. Distal profile of anal fin straight to slightly convex. Unbranched anal-fin rays i (1), ii (21), or iii (11); branched rays 7 (7) or 8 (26) [iii,8]. Forked caudal-fin lobes short, distally rounded, and of similar size. Caudal-fin rays i,17,i (33) [i,17,i]. Scales ctenoid (sensu Roberts, 1993); covering all of body. Lateral-line scale at vertical through dorsal-fin origin bearing 24 ctenii formed of independent ossifications along posterior margin of scale. Scales on humeral region and 33 Fig. 2. Pseudotympanum of Hemigrammocharax rubensteini, CU 89498, 23.7 mm SL, left side, anterior to left. Overlying skin and adipose tissue removed. Narrow white band horizontally crossing pseudotympanum is lateral-line nerve. Arrow indicates first pleural rib. dorsal portion of body immediately posterior to head smaller than remaining body scales. Lateral line straight, but incompletely pored with 35 (6), 36 (11), 37 (13), or 38 (3) [36] scales; last one or two scales extending beyond point of flexure along posterior margin of hypural plate. Pored scales 18 (1), 19 (1), 20 (1), 21 (4), 22 (3), 23 (8), 24 (5), 25 (2), 26 (3), 27 (4), or 30 (1) [23]. Pored portion of lateral line discontinuous in five specimens with 1 (2), 2 (2), or 3 (1) sequential non-pored scales at positions 16, 17, 18, 19, 20, 23, 24, or 26. Scale rows between dorsal-fin origin and lateral line 5 (33) [5]. Scale rows between pelvic-fin origin and lateral line 4 (15), 4.5 (17), or 5 (1) [4]. Middorsal scales to dorsal-fin origin 8 (2), 9 (8), 10 (16), 11 (6), or 12 (1) [10]. Scales from posterior terminus of dorsal-fin base to adipose fin 8 (15), 9 (16), or 10 (2) [9]. Scales between anus and analfin origin 2 (11) or 3 (22) [3]. Scale rows around caudal peduncle 12 (33) [12]. First gill arch with 11 or 12 gill rakers; branchiostegal rays 4; supraneurals 5; vertebrae 35(1), 36 (15), or 37(2). Well developed pseudotympanum composed of three muscular hiatuses delimited medially by anterior swimbladder chamber and laterally by adipose tissue and skin (Fig. 2). Anterior muscular hiatus triangular; bordered dorsally by lateralis superficialis muscle, anteroventrally by obliquus superioris muscle, and posteriorly by anterior margin of first pleural rib. Middle hiatus pentagonal and margined anteriorly and posteriorly by first and second pleural ribs, respectively, dorsally by lateralis superficialis muscle, anteroventrally by obliquus superioris muscle, and posteroventrally by obliquus inferioris muscle. Posterior hiatus overall ovoid; delimited dorsally by lateralis superficialis muscle, anteriorly by posterior surface of second pleural rib, anteroventrally by obliquus superioris muscle, posteroventrally by obliquus inferioris muscle, and posterodorsally by obliquus superioris muscle. Coloration in alcohol.—Overall color of head and body yellowish; darker dorsally (Fig. 1). Head with darker pigmentation most intense over fontanels, posterior portion of cranium and opercular region due to higher concentration of melanophores. Band of dark pigmentation extending 34 Copeia 2013, No. 1 Fig. 3. Life coloration of Hemigrammocharax rubensteini, Likouala River drainage, Republic of the Congo. Photo: J. P. Sullivan. from tip of snout and upper jaw to anterior margin of eye. Scale pigmentation more intense over distal region of exposed portion of scales resulting in overall reticulated pattern. Region of anus and urogenital papillae dark brown with pigmentation sometimes extending over anterior portion of anal-fin base. Dark brown longitudinal band extending along lateral surface of body from posterodorsal margin of opercle to dark caudal-peduncle spot. Anterior portion of longitudinal band darker and narrower than generally fainter posterior portion. Posterior portion approximately two scales high. Longitudinal band divided in some individuals to varying degrees into seven or eight dark blotches. Spot on caudal peduncle dark brown, rounded and extending onto bases of middle caudal-fin rays but falling short of dorsal and ventral margins of caudal peduncle. Dorsal, pectoral, and caudal fins with dark pigmentation along margins of rays but otherwise hyaline. Pelvic and anal fins with dark pigmentation densely scattered over interradial membrane. Coloration in life.—Melanophores on head, body, and fins as in alcohol-preserved specimens (Fig. 3). Dorsal portion of head olive brown and ventral region white. Eye and opercular region brownish with iridescent copper overlay. Dorsal and posterior regions of body olive brown. Abdominal region white with few melanophores and fainter reticulation pattern than dorsal portion of body. Caudal spot round, black, and extending slightly onto bases of middle caudal-fin rays. Base of dorsal and ventral caudal-fin lobes white with yellowish tint. Dorsal fin slightly yellow. Pelvic, anal, and caudal fins hyaline overall other than for scattered melanophores. Pectoral fin hyaline. Distribution.—Hemigrammocharax rubensteini is currently known from small tributaries of the Likouala River within the Odzala–Kokoua National Park, Republic of the Congo, in the northwestern portion of the Congo River basin (Fig. 4). Etymology.—The species name, rubensteini, is in recognition of David Rubenstein who generously funded the Rubenstein Fellowships of the Encyclopedia of Life at the National Museum of Natural History. Fig. 4. Map of central and northwestern portion of Congo River basin showing type locality of Hemigrammocharax rubensteini in Likouala River drainage. Dashed line represents borders of Republic of the Congo. Remarks.—Hemigrammocharax rubensteini fits the definition of the genus within the Distichodontidae in the combination of the presence of a single row of teeth on the jaws and an incomplete lateral line. Monophyly of the Hemigrammocharax–Nannocharax lineage is well supported by multiple morphological synapomorphies and retrieved in the molecular analysis by Calcagnotto et al. (2005). The monophyly of each genus is, however, questionable (Vari, 1979; Vari and Géry, 1981; Coenen and Teugels, 1989; Vari and Ferraris, 2004). Hemigrammocharax is now discriminated from Nannocharax in the incomplete versus complete poring of the lateral line, respectively; however, as discussed by Vari and Géry (1981), the distribution of these conditions is incongruent with that of several other synapomorphies proposed by Vari (1979). Degree of lateral-line poring is also variable Jerep and Vari—Hemigrammocharax from Congo 35 in some species of those genera (e.g., Hemigrammocharax multifasciatus, Nannocharax ansorgii, and N. maculicauda) and other species in the Characiformes (Roberts, 1967; Jubb and Gaigher, 1971; Vari and Géry, 1981), highlighting the possibility of independent reduction in the extent of poring. Hemigrammocharax rubensteini possesses 11 of the 12 synapomorphies proposed by Vari (1979:331) for the Nannocharax–Hemigrammocharax clade, lacking only the vertical expansion of the posterior strut of the lateral ethmoid contacting the orbitosphenoid (Vari, 1979:fig. 7, synapomorphy 101). Hemigrammocharax rubensteini largely lacks any ossified process or expansion on the posterior surface of the lateral ethmoid with a resultant lack of an articulation with the orbitosphenoid, although a narrow, poorly developed, posterior bony projection occurs on the left lateral ethmoid of one cleared-and-stained specimen in a location homologous with the posterior process found in most of the Distichodontidae. The lack of direct contact between the lateral ethmoid and the orbitosphenoid was observed by Vari (1979) in the distichodontid genera Nannaethiops and Neolebias, a hypothesized secondary loss within the context of the hypothesis of phylogenetic relationships within the Distichodontidae. We similarly hypothesize that the absence of the same posterior process in Hemigrammocharax rubensteini is a secondary loss under the phylogenetic hypothesis proposed by Vari (1979). The description of Hemigrammocharax rubensteini increases to ten the total number of valid species in the genus (Daget and Gosse, 1984; Coenen and Teugels, 1989). Members of Hemigrammocharax are widely distributed in the Congo, Cunene, Okavango, and Zambezi river basins but with 80% of the species occurring in the Congo basin: H. angolensis, H. lineostriatus, H. minutus, H. multifasciatus (also inhabiting the Zambezi System), H. ocellicauda, H. rubensteini, H. uniocellatus, and H. wittei (Daget and Gosse, 1984; Poll, 1973). Among these, only H. uniocellatus is sympatric and syntopic with H. rubensteini in the Lékoli River. evolutionary lineages (Malabarba, 1998) among South American characiforms; however, very little is known about the presence and morphology of this structure among African characiforms. Within the African family Alestidae, a pseudotympanum occurs only in Lepidarchus, which has a triangular hiatus in the musculature anterior to the first pleural rib (Zanata and Vari, 2005:88). The more complex pseudotympanum in Hemigrammocharax rubensteini spans more than two ribs with only the relatively small component anterior to the first pleural rib positionally comparable to that of Lepidarchus. That opening is complemented by a second portion between the first and second pleural ribs and a third component posterior to the second pleural rib. An extension of the hiatus to between the first and second ribs comparable to that in Hemigrammocharax rubensteini was described by Weitzman and Malabarba (1999:16) as a synapomorphy for Spintherobolus in the Neotropical characiform subfamily Cheirodontinae. This is an obvious convergence given the phylogenetic distance between these genera. The species of Spintherobolus additionally lack the muscular hiatus posterior to the second pleural rib found in H. rubensteini. We observed forms of the pseudotympanum similar to that occurring in Hemigrammocharax rubensteini in H. machadoi, H. multifasciatus, H. ocellicauda, and H. uniocellatus. Among members of Nannocharax, a pseudotympanum was observed in N. ansorgii, N. brevis, N. elongatus, N. fasciatus, N. intermedius, N. latifasciatus, N. lineomaculatus, N. macropterus, N. maculicauda, N. niloticus, N. occidentalis, N. parvus, N. procatopus, N. pteron, N. reidi, N. rubrolabiatus, N. schoutedeni, N. seyboldi, N. taenia, and N. usongo. Although not assessed in this study, it is probable that the remaining species of both genera possess a reduction or gap in the musculature in the pseudotympanum area. An evaluation of the morphological variation of the pseudotympanum and its phylogenetic significance in the Hemigrammocharax– Nannocharax clade is beyond the scope of this study. Pseudotympanum.—As mentioned above, Hemigrammocharax rubensteini is characterized by a well developed muscular hiatus in the humeral region, an opening referred to as the pseudotympanum. Such reductions or eliminations of portions of the body musculature lateral to the anterior portion of the swim bladder likely facilitate sound transmission to the anterior chamber of the swimbladder with sound vibrations then conveyed to the inner ear via the Weberian apparatus (Malabarba, 1998). Within the Characiformes, a pseudotympanum has been documented in multiple Neotropical taxa including some species of Characidium, family Crenuchidae (da Graça and Pavanelli, 2008; Silveira et al., 2008), and within the Characidae in some members of the subfamilies Aphyoditeinae (Aphyocharacidium, Microschemobrycon, and Tyttobrycon; Géry, 1973), Characinae (Acestrocephalus, Charax, Galeocharax, Phenacogaster, and Roeboides; Malabarba and Lucena, 1995; Lucena, 2003, 2007; Menezes, 2006; Lucena and Malabarba, 2010), across the subfamily Cheirodontinae (Malabarba, 1998; Weitzman and Malabarba, 1999; Bührnheim et al., 2008), and various incertae sedis species (Hyphessobrycon elachys, Leptagoniates pi, Paracheirodon axelrodi, Psellogrammus kennedyi, Rhoadsia altipinna, Tetragonopterus chalceus, and some representatives of the rosy tetra clade; Malabarba, 1998; Mirande, 2010). Details of pseudotympanum form and position have been used to diagnose species (Menezes, 2006) and define MATERIAL EXAMINED Hemigrammocharax angolensis: MRAC P.158822, paratypes, 3, 25.1–31.9 mm SL, Angola, Luita River, Xa-Ua, poste de Cuilo. Hemigrammocharax lineostriatus: MRAC P.159945–159949, paratypes, 5, 17.6–19.4 mm SL, Angola, mare Tchifuca. Hemigrammocharax machadoi: AMNH 215607, 10, 20.5– 21.8 mm SL, Zambia, Western Province, Kataba stream on Mongu-Senanga highway; MRAC P.159969, paratypes, 2, 20.5–20.7 mm SL, Angola, Longa River, tributary of Luena River, Nharicumbi village. Hemigrammocharax multifasciatus: AMNH 215614, 2, 31.2– 31.5 mm SL, Zambia, Western Province, Litoya stream on Mongu-Senanga highway; AMNH 217445, 4, 26.5–33.0 mm SL, Botswana, Ngamiland, Okavango River delta, Thamalakane River at Matlapenang bridge. Hemigrammocharax ocellicauda: CU 87637, 30, 22.3–30.9 mm SL, Republic of the Congo, Cuvette-Ouest, Likouala River Drainage, Lékoli River, Odzala National Park; CU 89163, 1, 24.2 mm SL, Republic of the Congo, Cuvette-Ouest, Likouala River Drainage, Lékoli River, Odzala National Park. Hemigrammocharax uniocellatus: CU 89494, 7, 23.6–26.1 mm SL, Republic of the Congo, Cuvette-Ouest, Likouala River 36 Drainage, Lékoli River, Odzala National Park; CU 89495, 7, 20.2–26.9 mm SL, Republic of the Congo, Cuvette-Ouest, Likouala River Drainage, small canal around island in Lékoli River, Odzala National Park. Hemigrammocharax wittei: MRAC P.36247–36311, cotypes, 65, 27.1–34.9 mm SL, Kando River de Tenke. Nannocharax ansorgii: AMNH 228534, 3, 23.6–25.4 mm SL, Central African Republic, Chaine Des Bongos, control zone of Sangba, Bamingui river confluence with Ivingou River, 60 km downstream of Sangba base; NRM 38317, 9, 16.2– 21.2 mm SL, Gambia, MacCarthy Island, Gambia River drainage, ca 2 km NW Bansang, Farida Creek. Nannocharax brevis: CU 91688, 1, 38.3 mm SL, Central African Republic, Basee-Kotto, Oubangui River drainage, Oubangi River downriver from Mobaye; CU 91690, 3, 39.1– 50.7 mm SL, Central African Republic, Basee-Kotto, Oubangui River drainage, Oubangi River shoreline at uncompleted bridge at Mobaye. Nannocharax elongatus: CU 91667, 1, 50.6 mm SL, Central African Republic, Basee-Kotto, Oubangui River drainage, Oubangi River shoreline at uncompleted bridge at Mohaye. Nannocharax fasciatus: USNM 303754, 5, 26.2–32.3 mm SL, Cameroon, Southwest Province, Manyu, Cross System, main Cross River downstream of Mamfe, Mamfe River junction with Cross River; USNM 303756, 2, 36.0–41.3 mm SL, Cameroon, Southwest Province, Manyu, Cross System, main Cross River downstream of Mamfe, main Cross River ca 23 km below Mamfe. Nannocharax intermedius: MCZ 32508, 1, 47.9 mm SL, Ja River at Bitye; SU 15579, 4, 39.0–45.5 mm SL, Cameroon, Menyoo River, Ntem River Drainage, Ambam. Nannocharax latifasciatus: USNM 303996, 3, 32.8–49.5 mm SL, Cameroon, Southwest Province, Manyu, Cross System, main Cross River downstream of Mamfe, Northern Munaya River junction with Cross River. Nannocharax lineomaculatus: MHNG 2433.045, 10 of 16, 21.9–32.6 mm SL, Central African Republic, BaminguiBangoran, river in Gounda, along route Ndele-Birao. Nannocharax macropterus: AMNH 247845, 1, 65.9 mm SL, Democratic Republic of Congo, Kasai Occidental, Lulua, Nsanga Nyembo; AMNH 247846, 2, 43.9–56.5 mm SL, Democratic Republic of Congo, Kasai Occidental, Lulua, Ntumba Shambuyi; MCZ 48055, 2, 35.9–37.6 mm SL, Ghana, Ongwa, and Prah rivers at or near Twifu Prasu. Nannocharax maculicauda: CU 80621, 1, 30.6 mm SL, Gabon, Woleu-Ntem, Ngomo River where it crosses road from Oyem to Bitam; USNM 224524, 3, 23.5–28.7 mm SL (1 CS), Gabon, Ogooue Ivindo, still arm of upper Ivindo River opposite Bourassie, Gabon, at juncture of Djouah and Karouaga rivers. Nannocharax niloticus: AMNH 50826, 4, 29.3–37.7 mm SL, Egypt, Nile River; FMNH 54288, 2, 36.8–36.9 mm SL, Egypt, Nile at Luxor. Nannocharax occidentalis: CU 91678, 2, 26.9–38.5 mm SL, Central African Republic, Nana-Grébiz, Gribingui/Chari drainage, Grinbingui River at Kanga Bandoro. Copeia 2013, No. 1 Nannocharax parvus: MRAC 90-57-P-2159-161, 3, 31.8– 40.4 mm SL, Congo Brazzaville, Ngoombi River, tributary of Dola River, Loc Dinga basin. Nannocharax procatopus: MHNG 1248.26, 1, 58.2 mm SL, Congo, Kalubadi, Lulua River. Nannocharax pteron: ANSP 65560, holotype, 45.5 mm SL, Central African Republic, Tomi River, tributary of Ubangi, at Fort Sibut, Ubangi-Shari, French Equatorial Africa. Nannocharax reidi: USNM 304046, holotype, 62.7 mm SL, Cameroon, Cross River system, southern Munaya River draining northern Korup, on Basep River at junction with Munaya River; USNM 375193, paratypes, 16, 34.3–59.0 mm SL, 2 CS, Cameroon, Cross River System, southern Munaya River draining northern Korup, on Basep River at junction with Munaya River. Nannocharax rubrolabiatus: MRAC 95-22-P-1-7, 7, 45.4– 59.8 mm SL, Cameroon, Mi River, tributary of Lom River, Sanaga River basin, igoum. Nannocharax schoutedeni: AMNH 241889, 5, 22.9–29.7 mm SL, Democratic Republic of Congo, Salonga National Park, Ifumu, Luilaka River just downstream from Monkoto; AMNH 241891, 14, 14.4–39.3 mm SL, Democratic Republic of Congo, Salonga National Park, Luilaka River, Monkoto. Nannocharax seyboldi: USNM 118757, holotype, 32.9 mm SL, Liberia, Bellyella; USNM 118758, paratypes, 3, 34.8–41.3 mm SL, Liberia, Bromley. Nannocharax taenia: CU 91682, 3, 29.6–31.2 mm SL, Central African Republic, Ouaka, Ouaka/Oubangui drainage, Mbourou River at AXMIN Ndassima mine camp; CU 91684, 1, 35.0 mm SL, Central African Republic, Ouaka, Ouaka/Oubangui drainage, Baı̈dou River, above and below pontoon crossing. Nannocharax usongo: USNM 303795, 1, 27.7 mm SL, Cameroon, Southwest Province, Manyu, Cross System, main Cross River downstream of Mamfe, Mam River junction with Cross River. ACKNOWLEDGMENTS This project was made possible by support from the National Museum of Natural History, Smithsonian Institution and the Herbert R. and Evelyn Axelrod Chair in the Division of Fishes of the National Museum of Natural History. We thank B. Brown (AMNH), J. Friel (CU), and E. Vreven and M. Parrent (MRAC) for the loan of specimens. S. Raredon, J. Clayton, and L. Palmer provided assistance at USNM. Figure 1 was prepared by T. Griswold, Figure 2 by D. Johnson, Figure 3 by J. Sullivan, and Figure 4 by M. Tsuchiya. LITERATURE CITED Bührnheim, C. M., T. P. Carvalho, L. R. Malabarba, and S. H. Weitzman. 2008. A new genus and species of characid fish from the Amazon basin—the recognition of a relictual lineage of characid fishes (Ostariophysi: Cheirodontinae: Cheirodontini). Neotropical Ichthyology 6:663–678. Calcagnotto, D., S. A. Schaefer, and R. DeSalle. 2005. 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