Geophagus multiocellus, Mattos & Costa, 2018

Mattos, Jose L. O. & Costa, Wilson J. E. M., 2018, Three new species of the ' Geophagus ' brasiliensis species group from the northeast Brazil (Cichlidae, Geophagini), Zoosystematics and Evolution 94 (2), pp. 325-337 : 329-332

Geophagus multiocellus sp. n. Figs 4 , 5 , Table 3

Material.

Holotype. UFRJ 11764, 101.4 mm SL; Brazil: Bahia state: Iguaí municipality: Guaíra balneary, Rio Cambiriba , Rio Gongogi drainage, Rio de Contas Basin , 14 º 36′17′′ S 40 º 06′09′′ W, altitude about 345 m asl; W. J. E. M. Costa et. al., 18 June 2011.

Paratypes. UFRJ 8217, 6, 57.4-102.9 mm SL; UFRJ 8254, 5, 26.5-41.9 mm SL (DNA); CICCAA 01379, 2, 78.9-82.7 mm SL; collected with holotype. UFRJ 8222, 5, 63.3-68.4 mm SL; UFRJ 8246, 2, 35.1-35.7 mm SL (DNA); Brazil: Bahia state: Nova Canaã municipality: small stream crossing the road BA-262, between the villages of Nova Canãa and Poções, Rio de Contas Basin , 14 º 43′33′′ S 40 º 14′17′′ W, altitude about 545 m asl; W. J. E. M. Costa et. al., 18 June 2011 . MNRJ32263, 5, 7.8-9.6 mm SL, 1, 8.2 mm SL (C&S); Brazil: Bahia state: Poções municipality, stream of Rio Valentim drainage, Rio de Contas River Basin , 14°27'38"S, 40°03'34"W (approx.), altitude about 365 m asl; M. Cetra and M. Trindade. 02 February 2007 . MNRJ 22302, 47, 6.2-101.1 mm SL, 2, 7.2-7.9 mm SL (C&S); Brazil; Bahia state: Jequié municipality: Rio de Contas Basin , 13°51'22"S, 40°4'58"W (approx.), altitude about 270 m asl; P. A. Buckup, A. T. Aranda and F. A. G. Melo. 12 August 2001 .

Diagnosis.

Geophagus multiocellus is distinguished from all other species of the ' G. ' brasiliensis group by having small pale blue spots with minute bright blue dots on its centre, often vertically coalesced to form short bars on the caudal fin (vs. never a similar pattern). In addition, it is distinguished from G. rufomarginatus , G. obscurus and G. santosi by the absence of an oblique iridescent blue zone between humeral region and anterior portion of dorsal-fin base (vs. iridescent blue zone present); from G. rufomarginatus by having dorsal-fin lappets with grey or dark brown edges (vs. red); presence of denticles on gill-rakers of the first branchial arch (vs. absence); absence of longitudinal series of small light blue spots between anal-fin spines and rays (vs. presence); from G. santosi by having blue bands crossing anal-fin rays (vs. blue bands parallel to fin rays); from G. itapicuruensis by having XIV dorsal-fin spines (vs. XIII); lateral spot rounded (vs. elliptical); absence of a horizontal dark brown band on snout (vs. presence); and from G. brasiliensis by having longitudinal blue bands crossing the anal-fin rays (vs. transversal blue bands crossing the anal-fin rays); mouth subterminal (vs. subdorsal).

Geophagus multiocellus is also distinguished from all other species of the ' G. ' brasiliensis group by ten unique nucleotide substitutions: COI 279 (C> T), COI 363 (G> A), CYTB 30 (C> T), CYTB 147 (A> G), CYTB 195 (C> T), CYTB 841 (C> T), CYTB 873 (C> T), CYTB 945 (A> G), CYTB 1014 (T> C) CYTB 1023 (A> G); it is similar to G. itapicuruensis and G. santosi and distinguished from all other species of the ' G. ' brasiliensis group by three unique nucleotide substitutions: COI 678 (A> G), CYTB 114 (A> G), CYTB 927 (A> G).

Description.

Morphometric data appear in Table 3 . Medium sized species, largest specimen examined 102.9 mm SL. Body relatively slender and compressed. Dorsal profile slightly convex on head, convex from nape to end of dorsal-fin base, approximately straight on caudal peduncle; no adipose nuchal protuberance. Ventral profile convex from lower jaw to pelvic-fin insertion, nearly straight between belly and insertion of first anal-fin spine, about straight on anal-fin base, gently concave on caudal peduncle. Caudal peduncle approximately as deeper as long. Greatest body depth slightly anterior to first dorsal-fin spine insertion. Snout moderately pointed; nostrils located between tip of snout and anterior margin of orbit. Mouth subterminal, distal tip of maxilla not reaching vertical through anterior margin of orbit. Lower lip fold moderately deep. Lower jaw slightly shorter than upper one. Eye near dorsal profile of head. Opercle not serrated.

Insertion of first dorsal-fin spine slightly anterior to vertical line through posterior-most margin of opercular series. Tip of dorsal fin pointed, reaching 35-50% of caudal-fin length, shorter and rounded in specimens 41.0 mm SL or smaller. Tip of anal fin pointed, reaching 20-50% of caudal-fin length, shorter and rounded in specimens 41.0 mm SL or smaller. Caudal fin subtruncate. Pectoral fin trapezoidal with rounded extremity, posterior margin posteriorly reaching vertical through posterior margin of flank blotch.

Tip of pelvic fin pointed, short, reaching insertion of 3rd anal-fin spine in larger specimens; shorter and rounded in specimens 50.0 mm SL or smaller, reaching between urogenital papilla and insertion of first anal-fin spine. Pelvic-fin filaments absent. Anal-fin origin at vertical between insertion of 13th dorsal-fin spine and 1st dorsal-fin ray. Dorsal fin XIV-XV + 11-12 (26); anal fin III + 8-9 (26); pectoral-fin rays 14-15 (26); pelvic fin I + 5 (26). Caudal-fin rays vi + 16 + iii (4).

Side of head covered with cycloid scales, ventral surface of head and snout without scales. Chest, trunk and caudal peduncle covered with ctenoid scales. Scales on head smaller than scales on chest and flank. Dorsal and anal fins without scales. About one fourth of caudal fin covered with small delicate scales. Two scale rows between lateral lines. Scales of dorsal-fin origin row 5; scales of anal-fin origin row 6; longitudinal series of scales 26; cheek scale row 5; upper lateral line scales 18, lower lateral line scales 11 + 2; circum-peduncular scale rows 16.

Premaxillary teeth conical, hyaline with red tip, slightly curved posteriorly; one regular, outer row of teeth, increasing in size on symphysis; proximal teeth smaller and irregularly arranged. Dentary teeth with similar arrangement, but slightly smaller. Five branchiostegal rays. Urohyal with strong anterior constriction. Gill-rakers on first branchial arch: first ceratobranchial 11, articulation 1, first epibranchial 8. Ceratobranchial rakers short, blunt and denticulated, except on fourth ceratobranchial proximal margin and fifth ceratobranchial distal margin, conical and non-denticulated. Anterior teeth of third pharyngobranchial and fifth ceratobranchial small, thin and slightly curved anteriorly, posterior teeth larger, robust and circular in cross section. Distal posterior teeth of the fifth ceratobranchial laterally compressed and with one or two cuspids. Five or six dentigerous plate on fourth pharyngobranchial, with three or four fused. Fifth ceratobranchial subtriangular, with concave posterior margin. One supraneural. Proximal radial of dorsal fin 25 + 1; proximal radial of anal fin 8 + 1; pleural ribs 12; epipleural ribs 12; vertebrae 14 + 14.

Colouration in life.

Flank greyish brown with seven broad dark brown bars and one dark brown longitudinal stripe; dark brown bars and stripe often overlapped and without visible limits in live specimens, conspicuously delimited in preserved specimens. Longitudinal rows of golden spots on ventral part of flank, between pectoral-fin insertion and caudal-fin base; spots approximately occupying ventral half-length of scales. Rounded dark brown spot on fifth trunk bar, similar and smaller spot on middle of caudal peduncle. Humeral region with three metallic blue spots arranged in oblique row. Dorsum greyish brown, chest and belly greyish white.

Head greyish brown, ventral region lighter, branchiostegal region greyish white. Infra-orbital area with oblique row of small metallic greenish blue spots. Opercular region background colour greyish brown. Absence or up to five small elliptical metallic greenish blue spots spread through opercle. Iris golden brown, with greenish blue iridescence on anterior and posterior portions, and dark brown bar through orbit aligned with sub-orbit al stripe. Pale brown supra-orbital stripe extending from dorsal profile to postero-dorsal margin of orbit, and dark brown infra-orbital stripe, approximately vertical, running from ventral margin of orbit to sub-opercle. Dorsal fin brownish red; anterior portion with short, oblique metallic blue stripes, posterior region with transverse rows of small pale blue spots; dark brown pigmentation concentrated at first two dorsal-fin spines and distal half of third spine. Anal fin brownish red, with oblique metallic blue stripes, posterior-most region with longitudinal rows of small, elongated pale blue spots. Caudal fin brownish red with small pale blue spots with minute bright blue dots on its centre, often vertically coalesced to form short bars. Pectoral fin pale yellowish hyaline. Pelvic-fin spine light yellowish brown, anterior pelvic-fin rays light yellowish brown with metallic bluish stripes parallel to rays, region around last rays hyaline.

Colouration in alcohol.

Similar to colouration in life, except for metallic blue marks becoming dark brown on flank and light grey on fins; red and dark brown pigmentation faded.

Distribution.

Known only from the middle section of the Rio de Contas Basin, in altitudes between about 270 and 545 m above sea level, Bahia state, northeast Brazil (Fig. 3 ).

Etymology.

From the Latin multum (several) and ocellus (little eyes, jewels), an allusion to the presence of small pale blue spots with minute bright blue dots on its centre on the caudal fin.

Figures

Figure 3. Geographical distribution of the ' Geophagus ' brasiliensis species group in northeast Brazil: red star, G. itapicuruensis; red triangle, G. obscurus; yellow triangle, G. diamantinensis; red circle, G. santosi; black diamond, G. multiocellus; yellow circle, G. rufomarginatus. Raw data set source was obtained from Natural Earth public domain (http: // www. naturalearthdata. com).

Figure 4. Geophagus multiocellus, UFRJ 11764, holotype, 101.4 mm SL; Brazil: Bahia: Rio de Contas Basin. Scale bar 10 mm. Photograph by J. L. O. Mattos.

Figure 5. Caudal fin colour pattern. A Geophagus multiocellus, UFRJ 8217, topotype. B Geophagus santosi, UFRJ 9998, topotype. Scale bar 10 mm. Photographs by J. L. O. Mattos.