Hyphessobrycon savagei Bussing, 1966, 1967

Ota, Renata R., Carvalho, Fernando R. & Pavanelli, Carla S., 2020, Taxonomic review of the Hyphessobrycon panamensis species-group (Characiformes: Characidae), Zootaxa 4751 (3), pp. 401-436 : 427-430

Hyphessobrycon savagei Bussing, 1966

(Figs. 19–20, Tab. 6)

Hyphessobrycon savagei Bussing, 1966: 215 [original description, type locality: “ Puntarenas: Río Ceibo (260m) at IH, 6 km W of Buenos Aires turnoff”]—. Géry, 1977: 463 [diagnosis in key; within group “b”]—. Bussing, 1987: 87 [ Costa Rica; diagnosis in key, brief description, photo, distribution]—. Bussing, 1998: 108–111 [ Costa Rica; diagnosis in key; brief description, photo, distribution]—.Lima et al., 2003: 140 [listed; distribution]—. Zarske & Géry, 2002: 25 [diagnosis from Hyphessobrycon columbianus ; key to species; color pattern in life]—. Angulo et al., 2013: 992 [listed, Costa Rica]—. Angulo et al., 2015: 376 [type catalog].

Diagnosis. Hyphessobrycon savagei differs from all congeners, except from H. compressus , H. diancistrus , H. otrynus , and those belonging to the H. panamensis species-group, by the presence of one large bony hook per fin ray, anterodorsally oriented and surrounded by a fleshy area, on last unbranched and first branched anal-fin rays of mature males (vs. absence of hooks, or presence of small and numerous hooks per fin ray). Hyphessobrycon savagei can be distinguished from H. compressus by the absence of a black blotch on the dorsal fin (vs. presence), by the presence of predorsal series (vs. absence), and by presenting 31–34 scales in longitudinal series (vs. 41–48). It can be distinguished from H. diancistrus and H. otrynus by presenting the caudal fin hyaline (vs. dark-brown blotches on caudal-fin lobes in H. diancistrus ; distal third of caudal fin darkened in H. otrynus ). It differs from the remaining species of the H. panamensis species-group by presenting two humeral blotches equally pigmented, extending two to four longitudinal scale rows below lateral line, with contours and margins always well-defined (vs. one diffuse humeral blotch, in H. daguae ; second humeral blotch less conspicuous than the first, extending up to two longitudinal scale rows below lateral line, with posterior margin as a concentration of melanophores concentrated along longitudinal midlateral stripe, in H. bussingi , H. columbianus , H. condotensis , and H. panamensis ). It can be further distinguished from H. columbianus by the absence of a silvery-blue iridescent coloration on dorsal region of flanks in life (vs. presence), and by a lower body depth (33.3–45.5% vs. 46.0–50.3% SL). It also differs from H. bussingi and H. condotensis by presenting 19–24 branched anal-fin rays (mode = 23) (vs. 23-27, modes = 24 and 25, respectively). It can be distinguished additionally from H. panamensis by presenting the first humeral blotch very conspicuous (vs. inconspicuous or less conspicuous).

Description. Morphometric data in Table 6. Body compressed, greatest body depth slightly anterior to vertical through dorsal-fin origin. Dorsal profile of body slightly convex from upper lip to vertical through anterior nostril; straight or slightly convex from this point to distal tip of supraoccipital process. Slightly convex from tip of supraoccipital process to dorsal-fin origin; slightly convex from this point to adipose-fin origin; and slightly concave along caudal peduncle. Ventral profile of body convex from lower lip to anal-fin origin; roughly straight along anal-fin base; and slightly concave along caudal peduncle.

Jaws equal, mouth terminal. Premaxillary teeth in two rows; outer row with 1(1), 2(6), 3(31), or 4(17) tricuspid teeth; inner row with 4(1), 5(42), 6(16), 7(1), or 8(1) conical to pentacuspid teeth. Posterior margin of maxilla extending to vertical through anterior margin of pupil. Maxilla with 2(4), 3(42), 4(13) conical, tri- to pentacuspid teeth. Dentary with 4(44), 5(13) large tri- to pentacuspid teeth, gradually decreasing in size, followed by 10 conical and abruptly smaller teeth. Central cusp longer than lateral ones.

Scales cycloid, with few radii (4-10); circuli markedly anterior and marginally (dorsally and ventrally). Lateral line incompletely pored with 8(2), 9(6), 10(12), 11(21), 12(5), 13(7), 14(3), or 16(1) perforate scales. Longitudinal series, including perforate scales, with 31(13), 32(14), 33(25), or 34(3). Scale rows between dorsal-fin origin and lateral line 6(24), 6½(3), or 7(32). Scale rows between lateral line and pelvic-fin insertion 5(32), 5½(18), 6(26), or 6½(6). Predorsal series with 9(13), 10(33), 11(11), or 12(1). Single row of up to 13 scales covering base of anteriormost anal-fin rays. Circumpeduncular scales 13(5) or 14(42).

Dorsal-fin rays ii(60) or iii(1), 8,i(7), or 9(53). First dorsal-fin pterygiophore located between neural spines of ninth and 10 th (2) vertebrae. Adipose fin present. Pectoral-fin rays i,11(6), 12(41), or 13(13), distal tip of rays reaching pelvic-fin origin. Pelvic-fin rays i,6(1), or 7(58), distal tip surpassing anal-fin origin. Anal-fin rays iii(4), iv(50), or v(6), 19(3), 20(9), 21(14), 22(9), 23(16), or 24(7). Anal fin of mature males with large bony hooks. Caudal fin bifurcate, lobes approximately of same size, i,9/8,i rays.

First gill arch with 6(34), 7(21), 8(1) rakers on epibranchial, 1(60) on intermediate cartilage, 10(21), 11(34), 12(3), or 13(1) on cerato+hipobranchial. Branchiostegal rays 4. Total vertebrae 32(1), 33(1), supraneurals 4(1) or 5(1) (Fig. 20).

Color in alcohol. Background coloration beige to yellowish. Dorsal portion of head and middorsal region of body with dense concentration of melanophores. Region above and below pupil darkened. Infraorbitals and opercle beige, with few scattered melanophores, evenly distributed. Lower portion of maxilla and gular region with few scattered melanophores, slightly more concentrated on upper half. Two dark-brown humeral blotches, vertically elongated, separated by light-beige area. First humeral blotch conspicuous, with melanophores slightly more concentrated on superior area, extending four to five longitudinal scale rows above and three to four below lateral line. Second humeral blotch conspicous, with melanophores equally distributed, extending three to four longitudinal scale rows above and one or two below lateral line. Body sides with melanophores evenly distributed, except on anteroventral half, with few or without melanophores. Brownish to silvery longitudinal midlateral stripe, from second humeral blotch to caudal peduncle, more conspicuous on posterior region. Fins hyaline, with few melanophores; anterior half of dorsal fin, distal third of anal fin, and median caudal-fin rays with more concentration of melanophores. Abdominal region, from pectoral-fin origin to pelvic-fin end, without melanophores.

Color in life. Background color silvery. Dark markings as in preserved specimens. Region above anal fin purple iridescent. Dorsal and caudal fins orange. Pelvic and anal fins (especially next to hooks) bright red. Adipose fin yellow. Females with less intense color pattern ( Bussing, 1966, 1998).

Distribution. Hyphessobrycon savagei is known from the río Pírris and río Térraba, Pacífic coast of Costa Rica (Figs. 4 and 21).

Sexual dimorphism. Mature males with one large bony hook by ray, antero-dorsally oriented and surrounded by fleshy area, from the last unbranched (on fifth or sixth segments) to the third branched (on the six segment) analfin ray of mature males ( Figs. 5c and 6c ). Small hooks on distal segments of anteriormost anal-fin rays were not observed. Mature males with distal margin of anal fin almost straight, and no evident elongation on dorsal fin, and females with distal margin of anal fin falcate, with anteriormost anal-fin rays longer than posterior ones, forming a lobe.

Ecology and habitat. Hyphessobrycon savagei lives in coastal areas of streams and rivers in altitudes between 0-70 meters a.s.l., in both stagnant waters and rapids, with water temperatures ranging between 24-30ºC. It feeds on aquatic and terrestrial insects ( Bussing, 1998).

Material examined. 180 specimens (23.8–42.1 mm SL). All from Costa Rica. Type material. UCR 42-1, paratypes of Hyphessobrycon savagei , 43 (rd, 15, 23.8 – 40.7 mm SL): San José, creek Paja de Agua, 8 km Southern San Isidro del General, north side of road Interamericana , 09°19’10’’N 83°39’54.1’’W; W. A. Bussing & M. I. Bussing, 29 Jul 1966 . Non-type material. Puntarenas, río Térraba basin: ANSP 164253 , 100 (30, 27.5-32.6 mm SL, 2 c&s, 29.2-29.3 mm SL), culvert pool at Inter American Highway, ca. 20 km S of Palmar Norte; D. Fromm, 10 Mar 1989 ; UCR 112012, 575 (40, 28.9 – 34.9 mm SL), creek 200 m Southeast of río Salamá Nuevo on road Interamericana , 08°50’10’’N 83°17’49.2’’W; W.A. Bussing & O. Blanco, 05 Jan 1967 ; UCR 114014, 60 (25, 27.1 – 42.1 mm SL), creek 36, 12 km West of village río Claro on road Interamericana , 08°42’50’’N 83°09’9.8’’W; W.A. Bussing & O. Blanco 05 Jan 1967 ; San José: UCR 40001, 54 (20, 25.9 – 29.7 mm SL), río Pedregoso, 3 km West of San Isidro del General on farm Villa Nueva , 09°22’35’’N 83°43’44.2’’W; O. Blanco, 19 Jul 1966 ; UCR 1942001, 139 (40, 25.8 – 32.5 mm SL), Corcovado National Park, río Camoral, next to Sirena station , 08°28’50’’N 83°35’20’’W; J. Lyons, 07 Mar 1987 . Puntarenas, río Pírris basin: UCR 304002, 164 (40, 28.3 – 35.4 mm SL), tributary of the río Jicote, 0.5 km Southern of Loma, on road Puriscal-Parrita , 09°32’25’’N 84°23’14.7’’W; W. A. Bussing, R. Nishimoto, J. Perry & C. Mata, 16 Jan 1969 .

Figures

FIGURE 5. Radiograph of anterior portion of anal fin of mature males, showing large bony hooks of: a) Hyphessobrycon bussingi (NUP 22294, 33.7 mm SL), b) H. panamensis (LBP 2759, 34.8 mm SL), c) H. savagei (UCR 4201, 24.7 mm SL). Very small hooks can be present on distal segments of most anterior anal-fin rays (white traces on a and b).

FIGURE 6. Large bony hooks on the anal fin of mature males, surrounded by fleshy area: a) Hyphessobrycon bussingi (NUP 22294, 33.7 mm SL), b) H. panamensis (LBP 2759, 34.8 mm SL), c) H. savagei (UCR 4201, 24.7 mm SL).