Rhinotocinclus dani (Roxo, Silva & Oliveira, 2016), 2022

Reis, Roberto E. & Lehmann A., Pablo, 2022, A new genus of armored catfish (Siluriformes: Loricariidae) from the Greater Amazon, with a review of the species and description of five new species, Neotropical Ichthyology (e 220002) 20 (2), pp. 1-100 : 66-68

Rhinotocinclus dani (Roxo, Silva & Oliveira, 2016) , new combination

( Fig. 37 ; Tab. 7 )

Parotocinclus dani Roxo, Silva & Oliveira, 2016:127 (Type-locality: municipality of Peixoto de Azevedo, Mato Grosso State, small tributary of rio Peixoto de Azevedo, drainage of rio Teles Pires, rio Tapajós basin, 10°23’10”S 54°18’22”W. Holotype: MZUSP 120737).

Diagnosis. Rhinotocinclus dani is distinguished from all congeners, except for R. bockmanni, R. hera , R. pentakelis , R. marginalis n. sp., and R. loxochelis n. sp. by having the dominant color pattern formed by five dark bars on body well separated and distinct (Fig. 7D; vs. dominant color pattern formed by four or five wide dark bars partially coalesced or closed together, or formed by a dark stripe from the snout tip, through the eye and extending to end of caudal peduncle); having two separate light lines from snout tip diverging to each nostril (Figs. 6E,F; vs. light lines on snout absent, Y- or V-shaped); and by having teeth with yellow (Fig, 5C; vs. cusps brown or light ochre). Rhinotocinclus dani is further distinguished from R. britskii , R. discolor , R. eppleyi , R. kwarup , R. isabelae , R. longirostris , R. pilosus , R. polyochrus , R. variola , and R. yaka by lacking an adipose fin (vs. adipose fin present). Rhinotocinclus dani is further distinguished from congeners, except R. bockmanni , R. loxochelis n. sp., R. marginalis n. sp., and R. pentakelis by having small platelets at adipose-fin position (vs. small platelets absent). Rhinotocinclus dani is distinguished from R. bockmanni by lacking a triangular dark spot at the dorsal-fin membrane (vs. dorsal-fin dark spot present), and by having a conspicuous dark bar 2 on body (vs. bar 2 absent or inconspicuous). It is distinguished from R. hera by having small platelets at adipose-fin position (vs. small platelets absent) and yellow teeth cusps (vs. light ochre cusps); and from R. pentakelis by the shallower body (body depth 16.3– 18.3% vs. 18.4–20.8% SL; caudal peduncle depth 8.8–9.9% vs. 10.1–11.7% SL; head depth 38.0–43.5% vs. 43.6–49.5% HL) and shorter dorsal-fin spine (24.0–27.0% vs. 27.0–30.8% SL). Rhinotocinclus dani is further distinguished from R. loxochelis n. sp. by the regularly arranged dark bars on body (vs. dark bars on body somewhat fragmented and inclined, such that they connect to form a zig-zag pattern), the shallower caudal peduncle (8.8–9.9% vs. 10.3–11.2% SL) and smaller orbital diameter (13.6–16.7% vs. 16.9–18.1% HL); and from R. marginalis n. sp. by the body dark bars 2 and usually 3 reaching to the ventral midline (vs. dark bars barely passing lateral dark stripe), and more numerous premaxillary (19–28, mode 21; Tab. 1) and dentary (16–22, mode 19; Tab. 2) teeth (vs. fewer premaxillary, 12–18, mode 16, and dentary, 11–16, mode 13, teeth).

Geographical distribution. Rhinotocinclus dani occur in the rio Teles Pires and rio Jamanxim basins of the rio Tapajós drainage, in the states of Mato Grosso and Pará, Brazil ( Fig. 36 ).

Remarks. Extintion risk of Rhinotocinclus dani is currently not assessed.

Material examined. Rio Tapajós basin, Mato Grosso State, Brazil: MZUSP 120737 , holotype (measured), cachoeira da Neblina in tributary to rio Peixoto de Azevedo, rio Teles Pires basin , Peixoto de Azevedo, 10°23’10”S 54°18’22”W . MZUSP 96194 , 20 paratypes (3 measured), island on rio Teles Pires , Paranaíta, 09°27’31”S 56°29’19”W. MZUSP 96225 , 5 paratypes (2 measured), marginal lagoon from gold mining activities in rio Tapajós , Paranaíta, 09°25’44”S 56°32’36”W . INPA 35523 , 37 (7 measured) , MCP 54756 , 13 (7 measured) + 2 cs, rio Paranaíta , Paranaíta, Mato Grosso, 09°30’57”S 56°42’36”W . MCP 32676 , 3 (1 measured) + 2 cs, rio Kaiapá on road MT-320 , ca. 5 km N of Nova Canaã do Norte, 10°36’16”S 55°42’26”W.

Figures

FIGURE 36 | Geographic distribution of Rhinotocinclus species of the R. bockmanni group in southeastern Amazon basin. Rhinotocinclus bockmanni (black dots); R. dani (red dots); R. hera (pink dots); R. loxochelis n. sp. (blue dots); R. marginalis n. sp. (white dots); R. pentakelis (yellow dots). T = Type-locality.

FIGURE 37 | Rhinotocinclus dani, MCP 54756, 26.1 mm SL, female, rio Paranaíta, Paranaíta, Mato Grosso, Brazil.