Triportheus albus Cope, 1872

Malabarba, Maria Claudia S. L., 2004, Revision of the Neotropical genus Triportheus Cope, 1872 (Characiformes: Characidae), Neotropical Ichthyology 2 (4), pp. 167-204 : 184-186

Triportheus albus Cope, 1872

Fig. 13

Triportheus albus Cope, 1872: 264 (type-locality: “from the Ambyiacu”).

Chalcinus albus . Garman, 1890:6 (description, Chalcinus knerii Steindachner, 1876 as synonym). Fowler, 1906:447 (description; type-material listed). Jordan, 1919:363 (designation of “logotype”). Triportheus albus . Fowler, 1945:154 (listed; synonyms).

Chalcinus knerii Steindachner, 1876:50 (type not seen) typelocality: Tefé [rio Solimões].

Chalcinus rotundatus iquitensis Nakashima, 1941:65 (type locality: Porto de Iquitos).

Diagnosis. An elongate Triportheus species reaching 151 mm SL (depth at dorsal-fin origin, 23.2-30.4, mean = 27.6% SL, n = 81; depth at pectoral-fin insertion, 24.2-33.2, mean = 28.8% SL, n = 79). The presence of 1 longitudinal scale row between the pectoral-fin insertion and the ventral keel distinguishes this species from all deep-bodied Triportheus species all of which have 2 longitudinal scale rows between the pectoral-fin insertion and the ventral keel. The combination of the possession of 32-35 lateral line scales, 24-28 branched anal-fin rays, and 30-39 gill rakers on the lower limb of the first gill arch distinguish T. albus from elongatebodied congeners except T. brachipomus . T. albus is distinguished from T. brachipomus by the length of the postorbital region of the head (43.3-48.9% of HL, mean = 45.8,n = 30 versus 36.1-44.6% of HL, mean = 39.9, n = 30 in T. brachipomus ), and the distance from the insertion of posterior most dorsal-fin ray to the adipose-fin origin (20.2-23.2% of SL, mean = 21.4, n = 30 versus 14.5-21.2% of SL, mean = 17.4, n = 30 in T. brachipomus )

Description. Morphometric data for Triportheus albus presented in Table 9. Body elongate and compressed laterally. Greatest body depth located slightly posterior to vertical through pectoral-fin insertion. Dorsal profile of head convex from upper lip to nares; nearly straight from nares to rear of head. Dorsal profile of body gently convex from rear of head to dorsal-fin origin; posteroventrally slanted along dorsal-fin base; straight from posterior terminus of dorsal-fin base to caudal peduncle; slightly concave along caudal peduncle. Dorsal portion of body transversely rounded.

ventrally, completely pored from supracleithrum to base of

caudal-fin rays. Thirty-two to 35 (mean = 33.6, n = 75) scales

in lateral line (50% of specimens with 34 scales); 5 scale series

between lateral line and dorsal-fin origin; 1-2 scale rows from

lateral line to pelvic-fin insertion. A series of large scales

between pectoral-fin insertion and midventral keel; 9-14 (mean

= 11.5, n = 68) scales along mid-dorsal line between tip of

supraoccipital process and dorsal-fin origin. Four or 5 rows

of scales on caudal peduncle.

Dorsal-fin rays ii,9; anal-fin rays iii,24-28 [26] (mean = 25.4,

n = 78); pectoral-fin rays i,10-13 [10] (mean = 11.1, n = 78);

pelvic-fin rays i,6. Dorsal-fin margin straight, situated on pos-

terior one-half of body; base of last dorsal-fin ray located

PROOFS rior Caudal tending

anterior branched fin over to emarginate vertical proximal anal-fin through rays one-third or forked much anal-fin of; scaled longer pelvic origin only than fin.. Pectoral basally Five following most. Middle fin anterays ex-.

caudal-fin rays terminate at or slightly beyond posterior mar- Ventral profile of head vertically straight from dorsal bor- gin of remainder of fin. der of lower lip to anteroventral margin of dentary; very Total vertebrae 38 [37]. slightly convex from that point to isthmus. Ventral profile of body distinctly convex from isthmus to pelvic-fin insertion; Coloration in alcohol. Overall ground color yellowish brown. nearly straight from that point to anal-fin origin; Body with diffuse, mid-lateral, silver stripe extending posteriposterodorsally slanted along anal-fin base; slightly con- orly from supracleithrum to caudal peduncle; stripe expandcave along caudal peduncle. Prepelvic region ventrally ex- ing vertically posteriorly. Body brownish dorsal to midlateral panded with midventral keel. stripe; light yellow ventral to stripe. Pectoral fin dark pig- Head obtusely pointed in profile; snout nearly straight in mented along first rays. Dorsal and anal fin sparsely pigprofile. Mouth terminal; lower jaw equal to upper jaw. Nos- mented with dark chromatophores. Distal tips of anal-fin rays trils of each side close together; anterior opening circular; dark. Caudal-fin darkly outlined; series of chromatophores posterior kidney-shaped. Eye large, without adipose eyelid. distributed on anterior one-third of caudal-fin rays. Gill rakers thin and close together; gill-rakers length about one-half of branchial filament length; gill rakers on Distribution. Rios Amazonas, Tocantins and Araguaia balower limb of first gill arch 30-39 [32] (mean = 35.2, n = 74). sins ( Fig. 12 ).

Type-material remarks. Cope (1872: 264) did not provide a catalog number for the type material of Triportheus albus , but only described it as “total length m..061; length to basis of dorsal fin.0292; from D.I to basis caudal.02” and refers to the type locality as “the Ambyiacu”. Subsequently, Fowler (1906:447) listed the type as ANSP 21234. The holotype is a very damaged young specimen lacking the ventral margin of the body.

No type was designated for Chalcinus rotundatus iquitensis by Nakashima (1941) and the synonymy of that species into T. albus in this paper is based on information in the original description, in particular the 31 lateral line scales and 17+35 gill rakers (“branquiespinas”). Chalcinus rotundatus iquitensis is an homonym of Chalcinus elongatus iquitensis Nakashima (1941:63) described in the same paper.

The types of Chalcinus knerii could not be located at NMW (H. Wellendorf pers. comm., Feb.1999). The single lot identified as Chalcinus knerii in that collection (NMW 12562- 63), is not labeled as type, and contains two specimens, instead of the one described by Steindachner. Although one of these specimens fits the length provided in the original description of C. knerii , it was collected in rio Negro, rather than “ Amazonas (bei Teffe?)” as cited in the original description. Nonetheless, some data in the original description (lateral line scales 34, anal-fin rays 29, scale series above lateral line 5) suggests that C. knerii is a junior synonym of Triportheus albus .

Type- material. Triportheus albus , holotype, ANSP 21234 , 54.4 mm SL, Peru, río Ambyiacu , J. Hauxwell .

Non-type material. Bolivia: Beni: UMMZ 204248 (10), río Itenez (= rio Guaporé ), opposite Costa Marques (12º29’S, 64º16’W) . Brazil: Amazonas : INHS 66933 (11), lago Marchantaria (4°4’S, 59°7’W) ; INHS 65906 (7) lake Terra Preta , about 8 km SW Manaus (4°12’S, 59°57’W) ; INHS 73035 (1 of 4), lago Marchantaria , Camaleão Inlet, about 12 km S Manaus (4°4’S, 59°7’W) ; MZUSP 58853 (8), rio Negro, São Gabriel da Cachoeira (0°7’S, 67°5’W) ; MZUSP 5852 (10 of 14), rio Negro, Manaus (3°10’S, 60°0’W) . Roraima: MZUSP 30509 (5), rio Branco , Marara (1°2’N, 62°10’W) . Goiás: MCP 17210 (4 of 5), lakes of rio Araguaia , near Luis Alves (13º14’S, 50º35’W) . Mato Grosso: MZUSP 53590 (4), rio Araguaia, furo near Aldeia Fontoura. Pará: MCP 15160 (1), rio Tapajós , in the Centro Educacional Boas Novas, Itaituba (4°16’S, 55°59’W) ; FMNH 56496 (8), Santarém (0°57’S, 46°59’W) . Ecuador: Napo: FMNH 103053 (8), río Napo at Destacamento Tiputini (0º47’S, 75º33’W) ; FMNH 94414 (3), río Napo, at Coca , beach in middle of river just upstream from bridge (0º27’S, 76º54’W) ; FMNH 103052 (6 of 11), río Yasuni , laguna Jatuncocha (1º0’S, 75º29’W) ; FMNH 103054 (1), río Tiputini , near mouth in río Napo and Quebradas (0º49’S, 75º31’W) . Peru: Loreto: INHS 38943 (8 of 9), Iquitos at Requena (03°44’S, 73°14’W) ; INHS 43617 (1), río Napo and Quebradas . Madre de Dios: USNM 295169 (2), Parque Nacional Manu, Pakitza and vicinity (7°16’S, 76°46’W) ; USNM 264028 (1), shore of island about 15 km downriver of junction of río Tambopata and río Madre de Dios (12°30’S, 69°8’W) ; MUSM 9676 (4), río Madre de Dios, Tambopata (12°30’49”S, 68°47’44”W) . Ucayali: USNM 280577 (1), Província Coronel Portillo, main channel and side pools of río Ucayali, 10 km upstream of Pucallpa (8°31’S, 74º22’W) .

Figures

Fig. 13. Triportheus albus, MUSM 9676, 114.64 mm SL, Peru, Madre de Dios, río Madre de Dios, Tambopata.

Fig. 12. Map of central and northern South America showing geographic distribution of T. culter (circles; asterisk = type-locality), T. albus (squares; asterisk = type-locality), T. nematurus (triangles; diamond = type-locality) and T. venezuelensis (lozenges; white square = type-locality) (some symbols represent more than one locality or lot of specimens).