Rineloricaria zawadzkii, Silva & Costa & Oliveira, 2022

Silva, Guilherme José Da Costa, Costa, Gabriel De Souza Da & Oliveira, Claudio, 2022, A new species of spiny Rineloricaria (Siluriformes: Loricariidae) from the Rio Paraíba do Sul basin and costal rivers from Rio de Janeiro State, Zootaxa 5175 (2), pp. 285-292 : 286-290

Rineloricaria zawadzkii , new species

Fig. 1 . Table.1 .

Rineloricaria nigricauda —Costa e Silva et al. 2015 [molecular delimitation]

Holotype. MZUSP 126857 , Male, 156.3 mm SL, São Paulo state, Guararema municipality, Rio Paraíba do Sul basin, 23º21’45.7”S 45º59’26.2”W 08 Abr 2008, A.P. Vidotto, R. Teixeira.

Paratype. All from Brazil, LBP 6444, 1, 133.6 mm SL, São Paulo State, municipality of Guararema, Paraíba do Sul river basin, 23º22’26.2”S 46º03’10.6”W, 09 April 2008, A.P. Vidotto, R Teixeira. LBP 6459. 3, 153,3–176.5 mm SL, São Paulo State, municipality of Guararema , Paraíba do Sul river basin, 23º22’08.5”S 46º01’28.3”W, 09 April 2008, A.P. Vidotto, R Teixeira. LBP 6465, 2, 136.6–157.3 mm SL, São Paulo State, Guararema municipality, Paraíba do Sul river basin, 23º22’08.5”S 46º01’28.3”W, 09 April 2008, A.P. Vidotto, R. Teixeira. LBP 11400, 1, 89.4 mm SL, Rio de Janeiro State, Cordeiro municipality, Paraíba do Sul river basin, 21º59’37.1” S 42º16’41.4”W 20 October 2010, C. Oliveira, G.J.C. Silva, K.Y. Abe. AO Ribeiro. LBP 21958, 2, 106.3–109.4 mm SL, Rio de Janeiro State, Casemiro de Abreu municipality, São João river basin, 22º28’31.2” S 42º09’01.2”W May 2010, D. Freitas, F. Lima. LBP 21958, 2, 106.3–109.4 mm SL, Rio de Janeiro State, Casemiro de Abreu municipality, Rio São João basin, 22º28’31.2” S 42º09’01.2”W May 2010, D Freitas, F Lima. MZUSP 14131 , 1 , 171.9 mm SL, Rio de Janeiro State, Macacu municipality, Rio Macacu basin, 22º32’0.0” S 42º50’0.0”W May 2010, Castro & Pompeu. MZUSP 121460 , 2 , 99.5 – 108.2 mm SL, Rio de Janeiro State, Conceicao de Macabu municipality, Rio Macaé basin, 22º11’56.0” S 41º50’23.0”W 2 May 2014, OT Oyakawa, P Camelier, M Melo, J C. Nolasco.

Non-Type. LBP 7919, 7, 72.3–110.4 mm SL, São Paulo State, municipality of Ubatuba, Rio Tavares basin, S 23°26’44.1’’ W 45°05’23.2’’, 12 December 2008, C. Oliveira. LBP 14355, 1, 67,3 mm SL, São Paulo State, municipality of Caraguatatuba, Rio Juqueriqueré basin, S 23°41’50.16” W 45°28’58.98”, 30 June 2011, GJC Silva, JM Henriques, JCP Alves, B Belo, R Devidé. LBP 14330, 1, 66.0 mm SL, São Paulo State, Municipality of São Sebastião, Rio Uma basin, S 23°43’28.02” W 45°44’1.80” .

Diagnosis. Rineloricaria zawadzkii can be distinguished from all congeners by have nuptial males with hypertrophied odontodes covering the lateral and dorsal region of the head and body, mainly in the lateral of the first half of the caudal peduncle (vs. nuptial male with hypertrophied odontodes covering the lateral of the head and dorsum of the head and pre-dorsal region). Additionally, Rineloricaria zawadzkii can be distinguish from all congeners, except R. aequalicuspis Reis & Cardoso, 2001 , R. anhanguapitan Ghazzi, 2008 , R. anitae Ghazzi, 2008 , R. aurata (Knaack, 2003) , R. baliola Rodriguez & Reis, 2008 , R. capitonia Ghazzi, 2008 , R. isaaci Rodriguez & Miquelarena, 2008 , R. jaraguensis (Steindachner, 1909) , R. kronei (Miranda Ribeiro, 1911) , R. latirostris (Boulenger, 1900) , R. maacki Ingenito, Ghazzi, Duboc & Abilhoa, 2008 , R. malabarbai Rodriguez & Reis, 2008 , R. maquinensis Reis & Cardoso, 2001 , R. microlepidogaster (Regan, 1904) , R. pentamaculata Langeani & de Araujo, 1994 , R. reisi Ghazzi, 2008 , R. rupestris (Schultz, 1944) , and R. tropeira Ghazzi, 2008 by a wide post-pectoral naked area (vs. slender post-pectoral naked area) (see figure 1). Moreover, Rineloricaria zawadzkii can be distinguished from R. aequalicuspis , R. anhanguapitan , R. capitonia , R. maacki , R. malabarbai , R. maquinensis , R. reis i and R. tropeira by abdomen completely covered by plates (vs. abdomen partially or completely naked). Rineloricaria zawadzkii can be distinguished from R. pentamaculata , R. rupestris , R. baliola and R. isaaci by having the naked area on the tip of the snout not reaching the first pore of the laterosensory system (naked area on the tip of the snout not reaching the first pore of the laterosensory system). Rineloricaria zawadzkii can be distinguished from R. anitae , R. jaraguensis , R. kronei , R. latirostris and R. microlepidogaster by having four lateral plate series in longitudinal rows below the dorsal fin, mid-dorsal series absent (or mid-dorsal series with 1–2 plates, sometimes asymmetric) (vs. five lateral plate series in longitudinal rows below the dorsal fin, the mid-dorsal series present with more than four plates).

Description. Morphometric data of holotype and paratypes in Table 1 . Body strongly depressed. In lateral profile, body slightly convex from the tip of the snout to the base of the dorsal fin and relatively flat from the base of the dorsal fin to the caudal peduncle. Head elongated with slightly convex lateral margin in dorsal view (figure 2). Snout with small, elliptical, naked area, not reaching the most anterior pore of infraorbital ramus of sensory canal. Eyes elliptical with large, deep postorbital notch. Lower lip covered by irregularly sized papillae well organized and arranged concentrically around oral cavity. Short maxillary barbel adorned with very small papillae; teeth acute and bicuspidate; dentary teeth larger than those of premaxilla; 5–7 (6) teeth on premaxilla and 5–7 (6) on dentary; lateral cusp smaller than the medial cusp.

Lateral surface of body entirely covered by plates, weakly keeled with odontodes along lateral line pores most developed than those on rest of body. Dorsal series with 22 plates. Mid-dorsal plates series absent. Median series with 26–28 (27) plates, bearing the laterosensory canal. Mid-ventral series with 16–19 (17). Ventral series with 23 plates. Abdomen entirely covered by plates, from opercular region to urogenital papilla. In large adult individuals (upper 120 mm SL) the base of the pectoral, pelvic and anal fins possess a narrow naked area. Lateral region of body, posterior to pectoral-fin insertion, with a broad naked area (see Vera-Alcaraz et al. 2012).

Dorsal fin II,7; its origin slightly posterior through pelvic-fin origin. Dorsal-fin unbranched ray (or second dorsal fin) slightly convex. Tip of adpressed dorsal-fin rays surpassing anal-fin origin. Pectoral-fin rays I,6; when adpressed its tip not reaching pelvic-fin ray insertion. Pelvic-fin rays i,5; its distal margin straight to slightly convex; tip of adpressed pelvic-fin ray not reaching anal-fin origin. Anal-fin rays i,5; distal margin slightly convex. Caudalfin rays i,10, i; truncate, with short, thin filament on upper caudal-fin ray.

Color in alcohol. Background color of dorsal surface of body brown, with five (or four) transverse dark brown bars, first on the base of the dorsal fin and four (or three) on the dorsum of the caudal peduncle. Dark bars inconspicuous in adult individuals, more apparent in juveniles. Caudal fin hyaline with dark brown basal bar and a dark brown terminal bar. Dorsal fin variegate, with a dark-brown terminal stripe. Pectoral and pelvic fins variegate, with a dark-brown terminal stripe. Anal fin hyaline or with a tiny and inconspicuous dark stripe on subterminal region.

Sexual dimorphism. Male specimens of Rineloricaria zawadzkii have hypertrophied odontodes over almost entire lateral surface, dorsal surface of trunk, and the dorsal surface of the spine of the pectoral fin. The odontodes are denser and longer on the side of the anterior half of the tail and the side of the head.

Distribution. Rineloricaria zawadzkii is known from main channel of Rio Paraíba do Sul, in coastal river from Rio de Janeiro State, such as Rio Macaé, Rio São João and Rio Macacu, and in coastal river from São Paulo State, such as Rio Tavares, Rio Juruqueré and Rio Una ( Figure 3 ).

Habitat. The juvenile specimens were collected in streams less than 1m deep with variable speed current. The adult specimens were collected in the main channel of the river associated with the mud bottom, occasionally in places deeper than 2m, which is unusual for the genus.

Etymology. The new species is named in honor of Dr. Claudio Henrique Zawadzki, an important taxonomist of Loricariidae , known among friends by the nickname “cabelo”, hair in Portuguese language. During investigations, the new species received the nickname “Cabeluda”, hairy in Portuguese, due to the large hair-like odontodes. A genitive noun.

Figures

FIGURE 1. Rineloricaria zawadzkii, MZUSP 126857, 156.3 mm SL, holotype, from São Paulo state, Guararema municipality, Paraíba do Sul river basin.

FIGURE 3. Map of registered points of Rineloricaria zawadzkii. Yellow star, type locality, red circles, samples from the Rio Paraiba do Sul basin. Red triangles, samples from coastal rivers of Rio de Janeiro State. Red diamonds, samples from coastal rivers of São Paulo State.