Hisonotus laevior Cope, 1894

Carvalho, Tiago Pinto & Reis, Roberto E., 2011, Taxonomic review of Hisonotus Eigenmann & Eigenmann (Siluriformes: Loricariidae: Hypoptopomatinae) from the laguna dos Patos system, southern Brazil, Neotropical Ichthyology 9 (1), pp. 1-48: 12-16

publication ID

1982-0224

persistent identifier

http://treatment.plazi.org/id/513387FA-1B09-FFB3-2609-5555C09CFB8B

treatment provided by

Carolina

scientific name

Hisonotus laevior Cope, 1894
status

 

Hisonotus laevior Cope, 1894  

Figs. 13, 14, 4b, 7b, and 8b

Hisonotus laevior Cope, 1894: 95   [original description, type locality: Rio Jacuhy, Rio Grande do Sul, Brazil]. - Regan, 1904: 268-269 [junior synonym of Otocinclus nigricauda   ]. - Gosline, 1945: 101 [listed as synonym of Microlepidogaster nigricauda   ]. -Fowler, 1959: 167 [listed as junior synonym of Microlepidogaster nigricauda   ]. - Schaefer, 2003: 322 [listed]. -Reis & Carvalho, 2007: 83 [listed]. - Ferraris, 2007: 248 [listed].

Otocinclus laevior   . - Isbrücker, 1980: 83 [listed].

Microlepidogaster laevior   . - Malabarba, 1989: 150 [listed]. Schaefer, 1997: 8 [listed].

Hisonotus leptochilus Cope, 1894: 96   new junior synonym [original description, type locality: Rio Jacuhy, Rio Grande do Sul, Brazil]. Regan, 1904: 268-269 [junior synonym of Otocinclus nigricauda   ]. - Gosline, 1945: 101 [listed as junior synonym of Microlepidogaster nigricauda   ]. - Fowler, 1954: 167 [listed as junior synonym of Microlepidogaster nigricauda   ]. - Schaefer, 2003: 322- 323 [listed]. -Reis & Carvalho, 2007: 83 [listed]. - Ferraris, 2007: 248 [listed].

Otocinclus leptochilus   . - Isbrücker, 1980: 83 [listed].

Microlepidogaster leptochilus   . - Malabarba, 1989: 150 [listed]. - Schaefer, 1997: 8 [listed].

Hisonotus nigricauda   , non ( Boulenger, 1891). - Ribeiro et al., 2007: 60 [misidentification, listed and illustrated].

Diagnosis. Hisonotus laevior   differs from its congeners, except from H. notopagos   and H. taimensis   by the higher number of median plate series 25-27 ( Table 2), vs. 20-25, by the number of predorsal plates 3-4 (modally 4; Fig. 7b), vs. 2- 3 predorsal plates, and by the vertebral count 30-31, vs. 25-29. Hisonotus laevior   is distinguished from H. notopagos   by the presence of a posterior notch articulation in the rostral plate, vs. notch articulation in the rostral plate absent; by the possession of a rounded caudal peduncle in cross section, vs. a slight square caudal peduncle in cross section; and by having the area anterior to nares unplated, vs. area anterior nares covered by plates. Hisonotus laevior   can be distinguished from H. taimensis   by the wider cleithral width 20.6-24.6%SL, mean 22.9%, vs. 18.5-21.3% SL, mean 20.0% ( Fig. 15), and by the higher body depth at dorsal-fin origin 16.2-20.8 % SL, mean 18.1%, vs. 13.3-16.3%, mean 15.1% ( Fig. 16).

Description. Morphometrics and meristics in Table 3. Adult size medium to large for members of this genus (larger specimen with 47.2 mm in SL). Body robust, somewhat elongated, without conspicuous keels. Caudal peduncle round in cross section. Dorsal profile straight to concave from tip of snout to nares, slightly convex from that point to dorsal-fin origin. Straight and posteroventrally sloped at dorsal-fin base and almost straight from that point to caudal-fin origin. Greatest body depth at dorsal-fin origin. Least body depth at posterior end of caudal peduncle. Posterior profile of caudal fin concave. Head and snout broad, snout rounded to slightly square in dorsal view, body progressively narrowing posterior of pectoral-fin insertion. Snout region anterior of nares concave, interorbital region convex. Upper margin of orbit slightly elevated. Eye dorsolaterally positioned. Iris operculum present.

Pectoral fin I,6. Pectoral fin posterior margin almost straight; its tip extending to middle of pelvic fin when depressed.Posterior margin of pectoral-fin spine smooth. Half portion of spine length serrate in smaller individuals (about or less than 30 mm in SL). Pectoral-fin axillary slit present, located below posterior bony margin of cleithral process. Pelvic fin i,5. Tip of depressed fin not reaching anal-fin origin in females, but extending beyond that point in males. Dorsal fin II,7. Dorsal-fin origin located slightly posterior of vertical through pelvic-fin origin. Dorsalfin spinelet present, laterally extended.Anal fin I,5. First analfin pterygiophore exposed anterior to anal fin or covered by ventral plate series.Adipose fin absent. Caudal fin i,14,i.

Body almost entirely covered by plates except for region overlying opening of swim bladder capsule, area between pectoral girdle and lower lip, region around anus, and area around base of paired fins. Rostral plate with posterior notch articulation for mesethmoid. Rostral plate thickened, with an odontodes-free band between dorsad and ventrad series of odontodes. Snout plates anterior to nares reduced, large paired unplated region between rostrum and nostril. Three or four rows of predorsal plates (modally four; Fig. 7b), smaller specimens sometimes presenting three rows. Lateral line incomplete, with small gap without pores along middle length of body, posterior portion of lateral line present. Median plate series extending to posterior end of caudal peduncle, not truncated. ( Fig. 4b). Median abdominal plate series small, irregularly arranged, sometimes presenting a naked area between median and lateral abdominal plate series. Lateral abdominal plates larger, forming a regular series, variable in number ( Fig. 8b). Coracoid and cleithrum exposed and covered by odontodes, except for median region of cleithrum between arrector fossae openings and medial region of coracoids.

Head, fin-spines, and body plates covered with odontodes, these larger on anterior surface of all fin spines, medially directed on pelvic fin. Odontodes on head and trunk of uniform size and distribution, except for enlarged odontodes on ventral and dorsal margin of rostrum. Anterior margin of rostrum presenting an odontode-free area. Odontodes on posterior parieto-supraoccipital tip not enlarged. Anteroventral margin of compound pterotic with median-to-large size perforations. Infraorbital canal entering infraorbital series via sphenotic. Lips roundish and papillose.

Premaxillary and dentary teeth slender proximally and flattened distally; bifid, major (medial) cusp large and rounded, minor (lateral) cusp pointed. Accessory patch of teeth absent on dentary and premaxilla.

Compound ventral hypural plate (hypurals 1-2) and compound dorsal hypural plate (hypurals 3-5) completely fused to each other or with slight median notch on the posterior margin of caudal-fin skeleton, Total vertebrae 30- 31 (5 c&s).

Color in alcohol. Ground color of dorsal and lateral surfaces of body light to dark brown. Dorsal and dorsolateral surface lighter than lateral surface.Ventral surface of body almost unpigmented except for scattered chromatophores. Dorsolateral surface of head and body with light longitudinal stripes. Stripes narrow, beginning at tip of snout anterior to nares, passing above orbit and reaching posterior end of parieto-supraoccipital, bifurcated and inconspicuous at this point and completely disappearing at vertical above dorsal-fin origin. Paired, dorsal and anal fins mostly hyaline, except for several transverse dark bands with chromatophores forming narrow transverse dark bands; bands most conspicuous on unbranched rays. Caudal fin completely dark brown, except for hyaline posterior portion of uppermost rays. That hyaline portion, and unbranched rays of caudal fin with striped pattern of transverse dark bands. In some specimens caudal fin with inconspicuous light transverse band, formed by rounded clear spots.

Sexual dimorphism. Urogenital papilla positioned just behind the anal opening in males. Adult males possess a fleshy flap along the dorsal margin of first thickened pelvic-fin ray, that is absent in females. Flap slightly wider basally and progressively narrowing distally. Adult males presenting a fleshy flap in the medial portion of first and second branched rays of pelvic fin. In juvenile males flaps are smaller or absent. Males have a longer pelvic-fin unbranched thickened ray that extends beyond the anal-fin origin, with the ray never reaching that point in females.

Distribution and habitat. Hisonotus laevior   is widely distributed in the laguna dos Patos system from southernmost tributaries of the laguna Mirim and canal São Gonçalo drainage to the tributaries of the northern rio Jacuí basin ( Fig. 17). The species is absent in the headwaters of the rio Jacuí basin. This species inhabits slow to median flowing watercourses, with clear to brown waters running over a sandy bottom, and is found in marginal or submerged aquatic vegetation. Hisonotus laevior   is sympatric along its distribution with several species of the genus. Hisonotus laevior   occurs in sympatry with H. armatus   along almost all its distribution. Hisonotus laevior   is collected together with H. nigricauda   in some localities of the laguna dos Patos system, mainly in the lower portions of the streams, and occurs in sympatry with H. notopagos   in the rio Camaquã drainage. Hisonotus laevior   occurs in the banhado do Taim together with Hisonotus taimensis   and in coastal plain of the Rio Grande do Sul with H. leucofrenatus   .

Remarks. Hisonotus laevior   is herein designated as a new senior synonym of Hisonotus leptochilus   ( Fig. 18). Both species were published in the same paper by Cope (1894). Herbert H. Smith collected these species in 1882, together with a collection of fishes sent to Academy of Natural Sciences of Philadelphia (ANSP). Edward D. Cope studied this material and described several new species including the two species of Hisonotus   , collected at Rio Jacuhy (rio Jacuí). According to Papavero (1973) and Malabarba (1989), Herbert H. Smith’s itinerary in the State of Rio Grande do Sul included several cities in the laguna dos Patos system and the localities of Caí (São Sebastião do Caí), São João do Montenegro ( Montenegro), and Porto Alegre. The later localities mentioned are situated in the lower portion of rio Jacuí and rio Caí drainages, where the species H. laevior   is the most abundant taxa of the genus. The descriptions of H. laevior   and H. leptochilus   were both based on a single specimen each. The differences between these taxa according to Cope (1894: 96) are: “The important characters which distinguish this species [ H. leptochilus   ] from the H. laevior   , are the thin and truncate lower lip with feeble tuberculation; the numerous ventral plates; the narrower orbital space, and the greater hispidity, especially of the head”. No substantial differences were found in the lower lip tuberculation between all Hisonotus species   examinated including the holotypes of H. laevior   and H. leptochilus   . The holotype of H. leptochilus   presents more plates in the abdominal median series than H. laevior   (see Cope, 1894 fig. 11b and fig. 12b, respectively). However, this is a polymorphic feature observed within some species of the genus and cannot be used to differentiate H. laevior   from H. leptochilus   .Another diagnostic feature used by Cope (1894) to differ H. leptochilus   from H. laevior   was the narrower interorbital space. Although the holotype of H. leptochilus   has a narrow interorbital width (39.5% of HL, vs. 41.6% of HL in the holotype of H. laevior   ), this measurement is within the range of H. laevior   (36.9-46.2% of HL; Fig. 19). Finally, no difference in the hispidity of odontodes, in any portion of the body, was found that could suggest the separation of these two species or any Hisonotus   in the laguna dos Patos system. For these reasons H. laevior Cope, 1894: 95   is considered senior synonym of H. leptochilus Cope, 1894: 96   . Hisonotus leptochilus   is here, for the first time, suggested as junior synonym of H. laevior   , although, both species had already been erroneously considered as junior synonyms of H. nigricauda   before (see synonym list).

Material examined. All from laguna dos Patos system, Rio Grande do Sul, Brazil. Rio Jacuí drainage: ANSP 21253 View Materials , holotype of Hisonotus laevior   , 39.2 mm SL, rio Jacuí   . ANSP 21564 View Materials , holotype of Hisonotus leptochilus   , 40.9 mm SL, rio Jacuí   . MCN 5823, 5, 14.8-30.7 mm SL, São Jerônimo, arroio da Porteira at fazenda Capão   . MCP 9302 View Materials , 2 View Materials , 28.7-30.2 mm SL, Pantano Grande, arroio Dom Marcos, 30º13’32”S 52º37’09”W GoogleMaps   . MCP 9533 View Materials , 3 View Materials , 23.2-27.6 mm SL, Rio Pardo , arroio Francisquinho on highway BR-290 between Butiá and Rio Pardo, 30º09’S 52º08’W GoogleMaps   . MCP 19835 View Materials , 12 View Materials , 25.6-40.2 mm SL, Amarópolis, creek tributary of rio Jacuí in the sylviculture Santo Amaro , 29º55’S 51º55’W GoogleMaps   . MCP 27329 View Materials , 2 View Materials , 26.0- 30.2 mm SL, Butiá, arroio Martins upstream of mine Recreio , 30º09’S 51º59’W GoogleMaps   . MCP 17359 View Materials , 11 View Materials , 18.9- 31.4 mm SL, Arroio dos Ratos , arroio da Porteira, 29º24’S 51º57’W GoogleMaps   . UFRGS 2577 View Materials , 2 View Materials , 29.7-39.9 mm SL, Triunfo, arroio Gil on road between Barreto and Montenegro, 29º48’S 51º37’W GoogleMaps   . UFRGS 9153 View Materials , 4 View Materials , 33.8- 43.2 mm SL, Candelária, riceculture canal near sanga das Oveiras, 29º48’00”S 52º36’58”W GoogleMaps   . Rio Vacacaí drainage   : MCP 23131 View Materials , 1 View Materials , 33.5 mm SL, São Sepé, rio São Sepé at bridge lateral to highway BR-153, about 3 km south from São Sepé , 30º11’08”S 53º33’35”W GoogleMaps   . Rio Caí drainage   : MAPA 1741 View Materials , 17 View Materials , 17.8-35.9 mm SL, São Sebastião do Caí , creek in Vila Conceição   . MAPA 1744 View Materials , 2 View Materials , 26.8 View Materials - 36.0 mm SL, São Sebastião do Caí , arroio Três Mares   . MAPA 1755 View Materials , 24 View Materials + 3 c&s, 19.7-43.4 mm SL, São Sebastião do Caí, creek in rio Branco , 29º35’S 51º22’W GoogleMaps   . MCP 23005 View Materials , 2 View Materials , 14.6-39.6 mm SL, Triunfo, arroio Bom Jardim, III Polo Petroquímico near   SITEL, 29º50’19”S 51º23’25”W GoogleMaps   . MCP 26053 View Materials , 1 View Materials , 40.3 mm SL, Lindolfo Collor, arroio Feitoria tributary of rio Cadeia , 29º34’54”S 51º14’03”W GoogleMaps   . UFRGS 8661 View Materials , 23 View Materials , 31.6 View Materials -43.0 mm SL, Butiá , creek on property Cerro Vermelho, 30º08’S 51º59’W GoogleMaps   . UFRGS 8720 View Materials , 38 View Materials , 30.4-46.1 mm SL, Rio Pardo , creek at fazenda Limoeiro, 29º59’S 52º22’W GoogleMaps   . UFRGS 8771 View Materials , 8 View Materials , 35.5-43.8 mm SL, Pantano Grande, creek on the border of fazenda Sanga Funda, 30º08’S 52º23’W GoogleMaps   . UFRGS 8777 View Materials , 2 View Materials , 36.4-48.1 mm SL, Rio Pardo , creek tributary of arroio Iruí at fazenda Limoeiro, 30º02’S 52º22’W GoogleMaps   . UFRGS 8786 View Materials , 16 View Materials , 28.8-43.6 mm SL, Pantano Grande, creek on the border of fazendas Tarumã I and Tarumã II, 30º08’S 52º23’W GoogleMaps   . Rio dos Sinos dranaige: MCN 18633 View Materials , 1, 47.2 mm SL, Sapucaia do Sul, pesqueiro at Parque Zoológico of Sapucaia do Sul. Rio Gravataí drainage: MCN 6003, 1, 29.8 mm SL, Santo Antônio da Patrulha , arroio Chicoloma   . MAPA 2626 View Materials , 4 View Materials , 32.9 View Materials -38.0 mm SL, Gravataí, arroio Passo dos Ferreiros, 29º56’S 50º58’W GoogleMaps   . MAPA 2354 View Materials , 1 View Materials , 33.4 mm SL, Santo Antônio da Patrulha, arroio Ramos between Santo Antônio da Patrulha and highway BR-290   . MAPA 2628 View Materials , 2 View Materials , 35.5-36.5 mm SL, Canoas, canal at south of rio Gravataí   . MCN 6062, 1, 39.7 mm SL, Gravataí, Banhado Grande at fazenda Quatro Irmãos   . MCP 14652 View Materials , 5 View Materials , 33.7-41.3 mm SL, Morungava, rio Morungava , 29º50’S 50º54’W GoogleMaps   . MCP 41574 View Materials , 2 View Materials , 36.2-40.8 mm SL, Gravataí , marsh at highway RS-118, BR-290, 29º58’S 50º56’W GoogleMaps   . Lago Guaíba drainage   : MAPA 1734 View Materials , 2 View Materials , 28.5 View Materials - 27.5 mm SL, Guaíba , creek at fazenda Juncal km 39 of BR-290   . MAPA 1848 View Materials , 5 View Materials , 32.5-43.8 mm SL, Porto Alegre, arroio Dilúvio between   PUCRS and UFRGS câmpus. MCN 14795 View Materials , 1, 39.1 mm SL, Mariana Pimentel, arroio Ribeiro Pequeno on road RS-711, 29º23’53”S 50º44’37”W GoogleMaps   . MCN 17567 View Materials , 2, 32.3-33.8 mm SL, Porto Alegre, arroio Lami on road of Quirinas   . MCP 16034 View Materials , 12 View Materials , 20.6-31.4 mm SL, Viamão, lago Guaíba at praia de Itapuã near to mouth of riacho Itapuã , 30º15’00”S 51º02’20”W GoogleMaps   . MCP 23466 View Materials , 1 View Materials , 40.9 mm SL, Viamão, arroio at praia da Pedreira, Parque Estadual de Itapuã , 30º21’30”S 51º02’48”W GoogleMaps   . MCP 28116 View Materials 27.1-42.8 mm SL, Viamão,arroio Sandu , 30º14’S 51º00’W GoogleMaps   . MNRJ 25597 View Materials , 1 View Materials , 31.5 mm SL, Barra do Ribeiro, creek on road between Barra do Ribeiro and Guaíba about 8 km from Barra do Ribeiro   . UFRGS 1239 View Materials , 1 View Materials , 38.1 mm SL, Viamão, arroio Alexandrina   . UFRGS 2346 View Materials , 7 View Materials , 19.2-37.8 mm SL, Eldorado do Sul, lago Guaíba at Vila Sans Soucy. Laguna dos Patos drainage   : MAPA 1753 View Materials , 7 View Materials , 24.1-42.3 mm SL, Tapes , arroio Teixeira on BR-116   . MAPA 1757 View Materials , 2 View Materials , 28.5-33.3 mm SL, Palmares do Sul, canal 16 km north of sanga Pangaré on road between Capivari and Mostardas.   MCN 2622, 1, 44.4 mm SL, Rio Grande , arroio Vieira, 32º06’S 52º09’W GoogleMaps   . MCN 12682 View Materials , 7, 32.0- 46.7 mm SL, São Lourenço do Sul, arroio Inhuquipá (Turuçu) near Formosa, 31º28’S 52º05’W GoogleMaps   . MCN 17632 View Materials , 3, 18.5 -40.0 mm SL, Palmares do Sul, channel of lagoa dos Gateados at fazenda São Sebastião do Fundo , 30º27’S 50º39’W GoogleMaps   . MCN 17549 View Materials , 1, 38.7 mm SL, Palmares do Sul, channel of lagoa dos Gateados at fazenda São Sebastião do Fundo , 30º27’S 50º39’W GoogleMaps   . MCN 18138 View Materials , 2, 32.5-32.6 mm SL, Palmares do Sul, south margin of lagoa do Casamento , 30º29’S 50º36’W GoogleMaps   . MCP 16016 View Materials , 6 View Materials , 14.7-34.8 mm SL, Viamão, creek on Varzinha at Itapuã , 30º19’S 50º56’W GoogleMaps   . MCP 19068 View Materials , 1 View Materials , 34.2 mm SL, Rio Grande, arroio Bolacha , 32º09’S 52º11’W GoogleMaps   . MCP 21375 View Materials , 6 View Materials , 25.6-40.5 mm SL, São José do Norte, laguna dos Patos at Barra Falsa upstream dam, 31º34’19”S 51º27’35”W GoogleMaps   . MCP 23856 View Materials , 10 View Materials , 31.6-43.8 mm SL, Sentinela do Sul, arroio Faxinal tributary of arroio Velhaco on road from Cerro Grande do Sul to Camaquã , 30º43’48”S 51º45’24”W GoogleMaps   . MCP 23859 View Materials , 2 View Materials , 27.1-41.8 mm SL, Sentinela do Sul, arroio Capivaras on road between Sentinela do Sul and VilaAurora. 30º39’27”S 51º36’12”W GoogleMaps   . MCP 23860 View Materials , 23 View Materials , 27.6-46.2 mm SL, Tapes, arroio Texeira on highway BR-116, 30º37’26”S 51º32’45”W GoogleMaps   . MCP 31157 View Materials , 4 View Materials , 31.7-33.2 mm SL, Rio Grande, Saco da Mangueira , 32º05’S 52º09’W GoogleMaps   . MCP 41575 View Materials , 23 View Materials , 25.1-42.7 mm SL, Sentinela do Sul, arroio do Tigre tributary of arroio Velhaco on road from Cerro Grande do Sul to Camaquã , 30º44’30”S 51º46’26”W GoogleMaps   . MCP 41576 View Materials , 2 View Materials , 31.4-31.9 mm SL, Sentinela do Sul, arroio Velhaco on road from Cerro Grande do Sul to Camaquã , 30º41’22”S 51º41’51”W GoogleMaps   . UFRGS 4220 View Materials , 3 View Materials , 22.2-35.9 mm SL, Tapes , arroio Velhaco between Tapes and Camaquã, about 24 km from mouth in laguna dos Patos, 30º45’S 51º38’W GoogleMaps   . UFRGS 6698 View Materials , 10 View Materials , 13.8-38.3 mm SL, Viamão, lagoa Negra, 30º21’35”S 50º58’34”W GoogleMaps   . Rio Camaquã drainage   : MCP 23854 View Materials , 12 View Materials , 34.8-44.7 mm SL, Cristal, creek tributary to arroio Santa Isabel on highway BR-116, about 17 km south from Cristal , 30º08’55”S 52º01’50”W GoogleMaps   . MCP 23857 View Materials , 21 View Materials , 27.8-38.9 mm SL, Camaquã, arroio Duro on road between Vila Aurora and Dom Feliciano, 30º45’34”S 51º51’57”W GoogleMaps   . MCP 25754 View Materials , 4 View Materials , 25.0- 37.2 mm SL, Camaquã, arroio Maria Ulghim on road between Camaquã and Vila Aurora, 30º49’S 50º49’W GoogleMaps   . MCP 26042 View Materials , 1 View Materials , 42.3 mm SL, Caçapava do Sul, arroio do Banhado highway BR-153 about 8 km northwest from Minas do Camaquã , 30º51’48”S 53º29’50”W GoogleMaps   . MCP 41607 View Materials , 1 View Materials , 36.7 mm SL, Caçapava do Sul, small creek tributary to arroio Hilário on road between Caçapava do Sul and Lavras do Sul, 30º44’24”S 53º44’51”W GoogleMaps   . UFRGS 8239 View Materials , 4 View Materials , 32.5-41.3 mm SL, Canguçu, creek tributary to rio Camaquã on highway RS-471, 31º23’S 52º40’W GoogleMaps   . UFRGS 8758 View Materials , 13 View Materials , 23.9-40.5 mm SL, Amaral Ferrador, creek at fazenda Ferraria, 30º52’S 52º15’W GoogleMaps   . MCP 44501 View Materials , 2 View Materials , 26.0-32.1, Pinheiro Machado, creek tributary to arroio Boici at fazenda Chimarrão , 31º13’44”S 53º22’18”W GoogleMaps   . Rio São Gonçalo drainage   : MCP 20821 View Materials , 6 View Materials , 37.8-39.4 mm SL, Pedro Osório, arroio Reduzino , 31º54’S 52º55’W GoogleMaps   . MCP 21424 View Materials , 13 View Materials , 33.4-48.9 mm SL, Herval , small creek tributary to arroioArambaré, between Pedro Osório and Airosa Galvão, 31º58’19”S 53º05’39”W GoogleMaps   . MCP 21144 View Materials , 4 View Materials , 31.5-37.3 mm SL, Piratini, arroio Piratinizinho on vicinal road to highway BR-293, 31º43’02”S 52º59’34”W GoogleMaps   . MCP 25153 View Materials , 19 View Materials , 33.1-46.3 mm SL, Pedro Osório, arroio Arambaré on road between Pedro Osório and Basílio, tributary of rio Piratini , 31º54’35”S 53º01’40”W GoogleMaps   . MCP 34778 View Materials , 1 View Materials , 37.6 mm SL, Herval, arroio Arambaré on road between Pedro Osório and Herval, 31º58’37”S 53º06’15”W GoogleMaps   . MCP 34779 View Materials , 8 View Materials , 33.3-48.8 mm SL, Pedro Osório, arroio Mata Olho on road between Pedro Osório and Basílio, 31º54’56”S 53º00’16”W GoogleMaps   . MCP 37683 View Materials , 4 View Materials , 31.7-41.7 mm SL, Pedro Osório, creek tributary to arroio Arambaré near Carvalho de Freitas , about 35 km from Pedro Osório on the railroad bridge, 31º57’52”S 53º06’17”W GoogleMaps   . Laguna Mirim drainage. MCP 26074 View Materials , 2 View Materials , 38.9-41.22 mm SL, Rio Grande, canal do arroio Taim, Estação Ecológica do Taim , 32º37’S 52º34’W GoogleMaps   .

MCP

Pontificia Universidade Catolica do Rio Grande do Sul

UFRGS

Universidade Federale do Rio Grande do Sul

Kingdom

Animalia

Phylum

Chordata

Class

Actinopterygii

Order

Siluriformes

Family

Loricariidae

Genus

Hisonotus

Loc

Hisonotus laevior Cope, 1894

Carvalho, Tiago Pinto & Reis, Roberto E. 2011
2011
Loc

Hisonotus nigricauda

Ribeiro, M & Kohler, A 2007: 60
2007
Loc

Microlepidogaster laevior

Schaefer, S 1997: 8
Malabarba, L 1989: 150
1989
Loc

Microlepidogaster leptochilus

Schaefer, S 1997: 8
Malabarba, L 1989: 150
1989
Loc

Otocinclus laevior

Isbrucker, I. J 1980: 83
1980
Loc

Otocinclus leptochilus

Isbrucker, I. J 1980: 83
1980
Loc

Hisonotus laevior

Ferraris, C 2007: 248
Schaefer, S 2003: 322
Gosline, W 1945: 101
Regan, C 1904: 268
Cope, E 1894: 95
1894
Loc

Hisonotus leptochilus

Ferraris, C 2007: 248
Schaefer, S 2003: 322
Fowler, H 1954: 167
Gosline, W 1945: 101
Regan, C 1904: 268
Cope, E 1894: 96
1894