Laemolyta fernandezi Myers, 1950: 197 Géry, 1964: 466 Géry, 1974: 157–159 Böhlke, 1953: 197 Eschmeyer, 1998: 574 Taphorn et al. , 1997:55–100 Lasso et al. , 2004:105–195 Laemolyta petiti Géry, 1964: 464 Santos et al ., 1984: 33 Eschmeyer, 1998: 1326 Anostomus ( Laemolyta ) fernandezi : Géry, 1977: 180 Revision of the South American freshwater fish genus Laemolyta Cope, 1872 (Ostariophysi: Characiformes: Anostomidae) Mautari, Kelly Cristina Menezes, Naércio Aquino Neotropical Ichthyology 2006 2006-03-31 4 1 27 44 6NRTL (Myers, 1950) Myers 1950 [278,682,1568,1592] Actinopterygii Anostomidae Laemolyta Animalia Characiformes 4 31 Chordata species fernandezi   Fig. 4      Laemolyta fernandezi Myers, 1950: 197, 198, [original description, typelocality: upper Orinoco];  Géry, 1964: 466[key to species];  Géry, 1974: 157–159, Fig. (3), p. 158 [complementary description, key to species];  Böhlke, 1953: 197[catalog of types];  Eschmeyer, 1998: 574[catalog]; Garavello & Britski, 2003: 73 [catalog];  Taphorn et al., 1997:55–100[catalog];  Lasso et al., 2004:105–195[list of species and distribution].     Laemolyta petiti Géry, 1964: 464, plate IV b [ typelocality: ilha do Bananal, upper rio Araguaia]; Santos & Jégu, 1989: 166, Fig. p. 196 [redescription];  Santos et al., 1984: 33[lower rio Tocantins];  Eschmeyer, 1998: 1326[catalog]; Garavello & Britski, 2003: 73 [catalog].     Anostomus( Laemolyta) fernandezi: Géry, 1977: 180[key to species, distribution].   Material examined.  93 specimens( 63.6–212.9 mmSL). Venezuela. Río Orinocosystem, upper Orinoco, 1925, C. Ternetz, CAS 116126, holotype, 73.1 mmSL. Anzoategui, río Orinocobasin, ANSP 166730, 5, 80.2–152.6 mmSL. Bolivar, río Orinocobasin, San Pedro de Tauca, ANSP 166532, 1, 137.0 mm SL. Bolivar, laguna Aricagua, floodplain, río Caura, Vispo Conrad, MHNLS 13061, 1of 2, 110.9 mmSL. Bolivar, laguna Guaiparo, San Felix, MHNLS 7063, 1of 3, 102.6 mmSL. Delta Amacuro, caño Guarguapo, in small tributary, approximately  500 mfrom mouth in río Orinoco, MZUSP 62448, 2, 80.6–109.8 mmSL. Brazil. Tocantins: upper rio Araguaia, ilha do Bananal, MHNG 2229.01, 1, 74.8 mmSL. Pará: Itupiranga, Tocantins, INPA 1546, 4, 136.1– 166.6 mmSL, INPA 1548, 5, 137.8– 156.7 mmSL, INPA 1888, 1, 141.5 mmSL. Rio Tocantins, Icangui, Projeto Tucuruí, INPA 1547, 7, 95.1– 141.7, INPA 12234, 14, 81.8–136.5 mmSL, INPA 15350, 6, 110.8– 162.2 mmSL. Rio Tocantinsbelow dam, Tucuruí, INPA 1549, 4, 168.3– 191.1 mmSL, INPA 16176, 2, 134.1– 164.2 mmSL. Rio Tocantins, poço do Paulo, below Tucuruí Dam, INPA 1889, 2, 87.5–89.3 mmSL. Rio Tocantins, Jatobal, above Tucuruí Dam, INPA 1890, 2, 183.2– 183.8 mmSL. Rio Tocantins, Tucuruímarket, INPA 1891, 2, 193.4– 201.3 mmSL. Rio Tocantins, INPA 15295, 2, 152.9– 191.3 mmSL. Rio Tocantins, reservoir above Tucuruí Dam, INPA 16176, 2, 134.1and 164.2. Rio Tocantins, lago Tauábelow Tucuruí, INPA 16177, 7, 132.5– 156.3 mmSL. Base Iof Tucuruíreservoir, INPA 16178, 5, 161.7– 193.7 mmSL. Base IVof Tucuruíreservoir, INPA 16179, 2, 198.3– 208.7 mmSL. Rio Xingu, Belo Monte, MZUSP 60180, 3, 172.8– 212.9 mmSL, MZUSP 60181, 4, 163– 178.7 mmSL. MZUSP 61947, 1, 164.9 mmSL. Mato Grosso: rio Araguaia, Santa Terezinha, MZUSP 20842, 7, 63.6–110.3 mmSL.   Diagnosis.  Laemolyta fernandeziis distinguished from all congeners by its deeper body (22.9–31.6 % vs.17.2–29.8 %, respectively, Fig. 5). It can be further distinguished from all  Laemolytaspecies, except  L. orinocensis, by having more lateral line scales (49–58 vs.40–47). Although  L. fernandezicannot be separated from  L. orinocensison the basis of this character, the latter species has a very conspicuous midlateral dark stripe, whereas in  L. fernandezithis stripe is inconspicuous and the transverse dark spots are much more evident than in  L. orinocensis.   Description. Morphometric and meristic data presented in Table 1. Body moderately large (SL = 63.6–212.9 mm). Dorsal profile of body straight or slightly concave from snout tip to end of supraoccipital spine, slightly convex from that point to origin of dorsal fin, straight and posteroventrally aligned along dorsal-fin base and straight or slightly convex from base of posterior most dorsal-fin ray to caudal peduncle. Ventral profile of body straight or slightly convex from anterior tip of lower jaw to region near isthmus and slightly convex from that point to anal-fin origin and slightly concave at region of pelvic-fin insertion. Upper limb gill-rakers 9–12 on first gill arch and 11–15 on lower limb.   Fig. 4.  Laemolyta fernandezi, CAS116126, holotype, 73.1 mm SL; Venezuela, upper río Orinoco.   Fig. 5.Scatter plot of body depth on standard length for all species of  Laemolyta. Scales small, 49–58 (51*, usually 53, Table 2) perforated along all of lateral line. Longitudinal scale rows from lateral line to dorsal-fin origin 7–8 (8*, usually 8), scale rows from lateral line to anal-fin origin 5–7 (7*, usually 6). Predorsal scales irregularly arranged. Scales rows around caudal peduncle 17–20 (19*, usually 18). Dorsal fin rays ii,10–12 (10*, usually 11); distal margin of fin slightly rounded. Anal fin short, slightly falcate, with ii–iii (iii, rarely),8–10 (8*, rarely 10) rays. Pectoral fin rays i,11–15 (14*, usually 14). Pelvic fin rays i,8; distal margin of fin truncate. Vertebrae 39–42 (42*, usually 39, N=30).  Color in alcohol.Adult specimens usually with dark, but sometimes very inconspicuous, longitudinal stripe, covering 1.5 to almost 3 longitudinal scale rows. Stripe extends from posterior region of opercle to caudal peduncle where it usually ends in form of darker triangular or oval spot. Upper region of body usually dark, with dark coloration extending ventrally to below midlateral dark stripe. Ventral region of body unpigmented from ventral limit of dark midlateral stripe on body to midventral one. Body with 4 transverse dark but sometimes inconspicuous bars or blotches, sometimes inconspicuous. First series situated between opercle and dorsal fin, but closer to opercle; second below dorsal fin, and usually more conspicuous; third located between pelvic and anal fins and last, anterior to adipose fin. First and second series usually more conspicuous and last series usually diffuse ( Fig. 6). Young specimens ( Fig. 7) with midlateral longitudinal stripe indistinct, extending from anterior part of snout to rear of caudal peduncle and usually finishing in form of triangular spot. Four transverse bars or blotches present in adults absent. Upper part of body sometimes with approximately 14 narrow transverse dark bars extending ventrally to near lateral line. Adult specimens sometimes retain faded transverse bars. Adult specimens from río Orinoco basin ( Fig. 8) with bars faded and midlateral longitudinal stripe on body very conspicuous. Dorsal, pectoral, and ventral fins hyaline with scattered dark chromatophores. Dark chromatophores also scattered along fin margin and over median rays of caudal fin. Adipose fin usually dark. Some specimens with 4 transverse dark bars quite evident, with dark blotch present on caudal peduncle and dark midlateral stripe on body faded ( Fig. 9).  Common name: Venezuela: Mije ( Lasso, 1992).   Distribution: Río Orinoco and Amazon basin (rios Xingu, Tocantinsand Araguaia) ( Fig. 10).   Remarks.  Laemolyta fernandezi Myers, 1950, was described based on a young specimen ( 73.1 mmSL), that was considered to be a new species in having a compressed body and more longitudinal scale rows (8/7) than  L. garmani,  L. proximaand  L. taeniata(4–6/4–7). According to Myers the specimen was collected in the upper río Orinoco, but the precise locality was not provided.   Fig. 6.Adult specimen of  Laemolyta fernandezi, INPA16178, 173.4 mm SL; Brazil, Pará, Base I Tucuruí Reservoir.   Fig. 7.Young specimen of  Laemolyta fernandezi, MZUSP20842, 63.6 mm SL; Brazil, Mato Grosso, rio Araguaia, Santa Terezinha.   Fig. 10.Geographic distribution of  Laemolyta taeniata(black dots; open circle = type-locality) and of  Laemolyta fernandezi(black squares; open squares = type-locality).   Fig. 8.Adult specimen of  Laemolyta fernandezi,ANSP166532, 137 mm SL; Venezuela, Bolivar, rio Orinoco basin, San Pedro de Tauca, L. Madera.   Fig. 9.Adult specimen of  Laemolyta fernandezi,INPA16177, 156.3 mm SL; Brazil, Pará, rio Tocantins, Lago Tauá below Tucuruí. The description of  L. petiti Géry, 1964, is also based on a young specimen ( 76.4 mmSL), collected in the rio Araguaia. When Géry (1964)described his new species he recognized its similarity with  L. fernandezi, but noted that a comparison between the two nominal forms was impossible because of the succinct description and lack of illustration of  L. fernandezi. Later on Géry (1974)redescribed  L. fernandeziand compared the data he obtained with those of  L. petitiand found that  L. fernandezihas fewer longitudinal scale rows (7–7 ½ / 6–6 ½), more lateral line scales (55) and a deeper caudal-peduncle than did  L. petiti.   Thecomparison of meristic and morphometric data among specimens of  L. fernandezifrom the Orinoco, Tocantins/ Araguaiaand rio Xingubasins revealed no significant differences between these populations. Thenumber of vertebrae in a sample from the río Orinocois 41 ( 10 specimens) and 42 ( 1 specimen- holotype) and from the rios Tocantins/Araguaia 39 ( 15 specimens), 40 ( 3 specimens) and 41 ( 1 specimen). The number of vertebrae in 4 specimensfrom the rio Xingubasin is 39 ( 1 specimen), 40 ( 2 specimens) and 41 ( 1 specimen). The comparison of body depth, that seemed to be visually different among the populations originating from the three basins mentioned, also did not show any significant difference ( Fig. 11).   Fig. 11.Scatter plot of body depth on standard length for populations of  Laemolyta fernandezi. In spite of the slight difference in number of vertebrae we prefer to recognize just one widely distributed species represented by allopatric populations, especially because no other meristic or morphometric differences were found to distinguish the populations.   Laemolyta fernandeziwas recorded from the rios Tocantinsand Araguaia by Santos & Jégu (1989) and is the most common anostomid species in the lower rio Tocantins( Santos et al., 1984). It is to date the only species of  Laemolytafound in the central portion of the rio Araguaia basin. In the lower rio Araguaia it occurs in sympatry with  L. garmani.   Laemolyta fernandezireaches 25 cmSL and eats small invertebrates (Santos & Jegú, 1989), vegetable material and periphiton ( Santos et al., 1984). Sexual maturity seems to occur in specimens at approximately 130 mmSL judging from direct observation of the gonads. Reproduction seems to occur during the flood season ( Santos et al., 1984). CAS, ANSP, MHNLS, MZUSP, MHNG, INPA C. Ternetz & Base I & Base IV Venezuela Rio Orinoco 500 rio Orinoco upper Orinoco 4 31 CAS 116126, ANSP 166730, 5, ANSP 166532, 1, MHNLS 13061, MHNLS 7063, MZUSP 62448, 2, MHNG 2229.01, INPA 1546, 4, 136.1, INPA 1548, 137.8, INPA 1888, INPA 1547, 7, 95.1, 141.7, INPA 12234, 14, INPA 15350, 6, 110.8, INPA 1549, 168.3, INPA 16176, 134.1, INPA 1889, INPA 1890, 183.2, INPA 1891, 193.4, INPA 15295, 152.9, INPA 16177, 132.5, INPA 16178, 161.7, INPA 16179, 198.3, MZUSP 60180, 3, 172.8, MZUSP 60181, 163, MZUSP 61947, MZUSP 20842 93 Tocantins holotype The Araguaia Orinoco 6 33 38 Tocantins holotype