Curimatella meyeri (Steindachner 1882)

Dorsal soft rays (total): 11 - 12; Analsoft rays: 9 - 10; Vertebrae: 35 - 37

Detritivore (Ref. 76754).

Curimatella meyeri (Steindachner)

Figures 14–19; TABLES 2, 5

Curimatus Meyeri Steindachner, 1882:113, pl. 1: fig. 4 [type locality: Peni: Río Huallaga].—Vari, 1989a, tables 2, 3 [phylogenetic relationships].

Curimatus serpae Eigenmann and Eigenmann, 1889a:7 [type locality: Brazil: Serpa (= Rio Amazonas at Itacoatiara)]; 1889b:418 [more extensive species description]; 1891:46 [reference].—Vari, 1989a, tables 2, 3 [phylogenetic relationships].

Curimatus meyeri.—Eigenmann and Eigenmann, 1889b:418 [Brazil: Óbidos, [reference].

Curimatella meyeri.—Fowler, 1906:296, fig. 3 [Peru].—Eigenmann, 1910:420 [reference].—Fowler, 1940:252 [Peni: Contamana]; 1942:207 [reference].—Eigenmann and Allen. 1942:291 [reference].—Fowler, 1945:115 [reference]; 1950:297, fig. 357 [literature compilation].—Ortega and Vari, 1986:11 [Peru: Amazon drainages; based on Fowler, 1950].

Curimatus (Curimatella) serpae.—Pellegrin, 1909:148 [Brazil: Santarém].

Curimatella serpae.—Eigenmann, 1910:420 [reference].—Femández-Yépez, 1948:25, fig. 7 [reference].—Fowler, 1950:297 [literature compilation]; 1975:364 [reference]. [New synonymy.]

Curimata reticulata Allen in Eigenmann and Allen, 1942:295, pl. 14: fig. 2 [type locality: Peru: Lago Cashiboya; additional material: Pera: Río Ucayali near Orellana].—Fowler, 1945:116 [Pera, reference]; 1950:290 [literature compilation]; 1975:364 [erroneously placed as a synonym of Anodus alburnus Müller and Troschel).—Vari, 1989a, tables 2, 3 [phylogenetic relationships].—Vari and Howe, 1991:19 [location of portion of type series). [New synonymy.)

Apolinarella meyeri.—Femández-Yépez, 1948:22, fig. 5 [designated as type species of Apolinarella Femández-Yépez).—Fowler, 1975:363 [reference].

Apolinarella reticulata.—Femández-Yépez, 1948:23 [assignment to Apolinarella].

Curimalella alburna serpae.—Géry, 1964a:36, fig. 37 [Peruvian Amazon).

DIAGNOSIS.—The 35 to 37 vertebrae of Curimatella meyeri discriminate the species from C. lepidura, C. dorsalis, and C. immaculata, which have 33 or fewer vertebrae. The 35 to 39 lateral-line scales to the hypural joint in C. meyeri and the relative depth of the caudal peduncle (0.11–0.12 of SL) further discriminate that species from C. immaculata, which has 33 or fewer lateral-line scales and a relatively deeper caudal peduncle (0.13–0.14 of SL). Curimatella meyeri lacks the distinctive mid-lateral spot on the caudal peduncle characteristic of C. dorsalis. Curimatella meyeri has 6 or 7 scales in a transverse series from the lateral line to the origin of the dorsal fin, in contrast to 9 to 10 scales in that series in C. lepidura. Curimatella meyeri differs from C. alburna in greatest body depth (0.30–0.36 of SL versus 0.37–0.41), depth of the caudal peduncle (0.11–0.12 of SL versus 0.13–0.14), and less discretely in the numbers of lateral-line scales to the hypural joint (35 to 39 versus 32 to 35), scales in a transverse series from the lateral line to the origin of the dorsal fin (6 or 7 versus 5 or 5), and number of vertebrae (35 to 37, most commonly 36, versus 33 to 35, most commonly 34).

DESCRIPTION.—(Available meristic and morphometric values for the holotype (see “Remarks”) are taken from the original species description (Steindachner, 1882) or are estimated from the accompanying illustration of the species (reproduced herein as Figure 14)).

Body elongate, moderately compressed. Dorsal profile of head convex from upper lip to vertical line through posterior nostril, straight or very slightly convex from that line to tip of supraoccipital spine in larger specimens, somewhat more convex overall in smaller individuals. Dorsal profile of body smoothly curved from tip of supraoccipital spine to origin of dorsal fin; straight and posteroventrally slanted at base of dorsal fin, straight from base of last dorsal-fin ray to caudal peduncle; degree of convexity somewhat variable (compare Figure 14 to Figure 18). Dorsal surface of body with indistinct median keel anterior to dorsal fin, smoothly rounded transversely posterior to fin. Ventral profile of body gently curved from tip of lower jaw to caudal peduncle. Prepelvic region transversely rounded anteriorly, very obtusely transversely flattened proximate to pelvic fin insertion; with median series of scales near base of pelvic fin. Scales of prepelvic region approximately of same size as those on adjoining regions of body. Obtuse median keel present posterior to pelvic fin insertion. Secondary obtuse keel on each side of postpelvic portion of body about two scale rows dorsal of ventral midline.

Greatest body depth at origin of dorsal fin, depth 0.29–0.36 [0.29], specimens from the western portions of the species range somewhat more slender-bodied than those from central Amazon; snout tip to origin of dorsal fin 0.44–0.50 [0.44]; snout tip to origin of anal fin 0.81–0.88 [0.82]; snout tip to insertion of pelvic fin 0.51–0.56 [0.52]; snout tip to anus 0.75–0.81; origin of dorsal fin to hypural joint 0.56–0.61 [0.59]. Margin of dorsal fin rounded distally, last unbranched and first branched rays approximately two to two and one-half times length of ultimate ray. Margin of pectoral fin pointed distally; length of pectoral fin 0.17–0.21, extends about one-half to two-thirds of distance to vertical line through insertion of pelvic fin. Pelvic fin pointed in profile, length of pelvic fin 0.20–0.24 [0.20], reaches about three-quarters distance to origin of anal fin in smaller individuals, somewhat less than two-thirds of distance in larger specimens. Caudal fin forked; rays of both lobes with exception of middle rays largely covered with dense sheet of small scales in all specimens above 60 mm SL. Scales overlying caudal fin distinctly smaller than those on posterior portions of caudal peduncle. Adipose fin well developed. Border of anal fin emarginate, anteriormost branched rays two and one-half to three times length of ultimate ray. Caudal peduncle depth 0.11–0.12 [0.11].

Profile of head distinctly pointed anteriorly, head length 0.28–0.33 [0.28]; upper jaw slightly longer than lower, mouth subterminal; snout length 0.29–0.36 [0.33]; nostrils of each side of head very close, anterior circular, posterior crescent-shaped with aperture closed by thin flap of skin separating nares; orbital diameter 0.27–0.34 [0.33]; adipose eyelid moderately developed, with broad, vertically ovoid opening over center of eye; length of postorbital portion of head 0.38–0.44 [0.44]; gape width 0.28–0.34; interorbital width 0.45–0.50 [0.45].

Pored lateral-line scales from supracleithrum to hypural joint 35 to 39 [35 or 36]; all scales of lateral line pored, canals in scales straight; 3 to 7 pored scales extend beyond hypural joint onto caudal fin base; 6 to 7 [6] scales in transverse series from origin of dorsal fin to lateral line; 4 to 5 [5] scales in transverse series from lateral line to origin of anal fin.

Dorsal-fin rays ii,9 or iii,9 [ii,9]; anal-fin rays ii,7 or iii,7 [ii,7]; pectoral-fin rays 14 to 16; pelvic-fin rays i,8 or 9 [i,8] (i,9 rare).

Total vertebrae 35 (9), 36 (98), 37 (3).

COLOR IN ALCOHOL.—Overall coloration of specimens retaining guanine on scales silvery-olive; ground coloration distinctly darker dorsal of lateral line. Ground coloration of specimens lacking guanine on scales tan ventral of lateral line, much darker dorsally. Scales dorsal of lateral line with crescent-shaped patch of dark chromatophores on exposed surface. Proportion of exposed surface of scale covered by dark pigmentation somewhat variable (see Figures 16–18). One lot of specimens from the Río Ucayali basin Peru (USNM 261499) very dark overall, with ground coloration masking patch of dark pigmentation on each scale. Mid-dorsal region of body immediately posterior of tip of supraoccipital spine with deep-lying, longitudinally elongate, dusky spot. Second, less elongate, deep-lying middorsal dusky spot immediately anterior of origin of dorsal fin. Two middorsal spots less apparent in larger specimens; masked by overall dark ground pigmentation and/or guanine on scales in some specimens. Median fins peppered with small chromatophores, particularly distally. Paired fins hyaline.


DISTRIBUTION.—Middle and upper Amazon basin (Figure 19).

DISTRIBUTION.—Rio Amazonas and Rio Tocantins basins (Figure 24).

MATERIAL EXAMINED.—136 specimens (55, 56.5–185.0).

GUYANA. Rupununi: no exact locality, CAS-IU 12289, 3 (66.2–82.6, formerly IU 12289). See Amucu (= Lake Amucu), ZMB 3527, 1 (75.8, lectotype of Anodus alburnus). Twoca Pan between Rupununi and Pununike.

BRAZIL. Pará: Santarém, USNM 148500, 1 (132.5). Santarém, Rio Maicá, MZUSP 9171, 1 (136.1). Lagoa along margin of Rio Tocantins, near Baião, MZUSP 21267, 31. Roraima: Rio Branco, Maraá, USNM 242141, 4 (129.7–159.0); USNM 268028, 3 (1, 71.5). Amazonas: Rio Negro, below Rio Daraá, USNM 311166, 2 (112.5–114.4). Paraná de Janauacá, USNM 229178, 1 (68.3). Lake Hyanuary (= Paraná do Janauari), MCZ 20267, 2 (139.1–151.9); MCZ 20346, 1 (91.5). Lago Janauari, near Manaus, MZUSP 6862, 6 (3, 84.4–145.7). Rio Negro, near Manaus, MZUSP 6687, 14 (2, 89.0–139.7). Manacapuru (= Lago Grande de Manacapuru), MCZ 20205, 11 (4, 151.0–179.9). Lago Jacaré, right bank of Rio Solimões, above Manacapuru, MZUSP 6452, 2 (98.0–123.3). Teffe (= Tefé), MCZ 20257, 1; MCZ 20253, 2. Rio Tefé, Mucura, USNM 242143, 1 (140.9). Igarapé Chefe, cabeceiras do Lago Beruri, MZUSP 6425, 1 (94.2). Lago Beruri, Rio Purus, MZUSP 6371, 1 (80.4). Lago Castro, mouth of Rio Purus, MZUSP 6309, 4 (86.5–96.4; 1 specimen cleared and counterstained for bone and cartilage). Lago Urini, mouth of Rio Japurá, MZUSP 36238, 1 (135.6). Coary (= Lago do Coarí), MCZ 20185, 1. Igarapé Xicanga, 5 km E of Humaitá, on Transamazonian Highway, USNM 311156, 1 (68.9). Jutahy (= Rio Jutaí), MCZ 20297, 1 (68.1, holotype of Curimatus alburnus lineatus); MCZ 20300, 1. Hyavary (= Rio Javarí along Brazilian-Peruvian border), MCZ 20234, 2. Mato Grosso: Rio Guaporé, Vila Bela de Santíssima Trindade, MZUSP 37515, 3 (160.0–170.0). Rio Branco, tributary of Rio Guaporé, above bridge along highway BR 364 between Cuiabá and Porto Velho, Município de Pontes e Lacerda, MZUSP 37422, 12.

PERU. Loreto: Río Ampiyacu, SU 36589, 1 (61.0, now in CAS). Río Yavari system, Río Yaquerana, NRM 26465, 1.

BOLIVIA. Río Guaporé, NMW 16366, 1 (185.0). Beni: Río Guaporé, AMNH 37706, 3 (67.5–82.9). Río Mamoré at 13°35′S, AMNH uncat., 5 (56.5–75.5). Río Madre de Dios, Laguna San Luis, MZUSP 27835, 3 (75.2–103.4). Río Blanco, USNM 278585, 2; USNM 278580, 5 (1, 93.8; specimen cleared and counterstained for cartilage and bone).

Porções altas e centrais da bacia amazônica.