Cambeva urubici, E. & Costa & M. & Feltrin & Katz, 2021

Costa, Wilson J. E. M., Feltrin, Caio R. M. & Katz, Axel M., 2021, Field inventory reveals high diversity of new species of mountain catfishes, genus Cambeva Katz, Barbosa, Mattos & Costa, 2018 (Siluriformes: Trichomycteridae), in south-eastern Serra Geral, southern Brazil, Zoosystema 43 (28), pp. 659-690 : 682-684

Cambeva urubici n. sp.

( Figs 10 , 11K , 12J , 13J ; Table 10 )

urn:lsid:zoobank.org:act:4F7C0D5A-4EC1-4D1D-9AFA-CEFE1973A810

MATERIAL EXAMINED. — Holotype. Brazil • 1 ex., 65.6 mm SL; Santa Catarina state: Urubici Municipality: Rio Urubici , Rio Canoas drainage, upper Rio Uruguai basin; 28°01’37”S, 49°35’21”W; about 935 m asl; C. R. M. Feltrin; 14.III.2021; UFRJ 6967 .

Paratypes. Brazil • 4 ex., 23.0-51.0 mm SL; collected with holotype; UFRJ 6973 • 2 ex., 28.3-61.0 mm SL; same locality and collector as holotype; 8.II.2021; UFRJ 6975 • 3 ex. (C&S), 31.2-47.3 mm SL, same data as for precedent; UFRJ 6976 • 4 ex., 19.1-32.0 mm SL; upper Rio Canoas , road between Urubici and Rio dos Bugres, 27°59’24”S, 49°32’39”W; about 905 m asl; C. R. M. Feltrin; 14.III.2021; UFRJ 6983 • 2 ex., 33.5-38.0 mm SL; same data as for precedent; CICCAA 04110 .

DIAGNOSIS. — Cambeva urubici n. sp. differs from all other species of the C. tropeira complex in having more opercular odontodes (15 or 16, vs 10 – 14), more teeth in the premaxilla and dentary (46-51 in both, vs 38-41 in the premaxilla and 31-39 in the dentary), a unique colour pattern, comprising three longitudinal rows of black spots on the flank in juveniles, with spots of the median row coalescing to form a black stripe along lateral midline (vs never a similar colour pattern), a robust autopalatine with a nearly straight medial margin ( Fig. 11K ; vs autopalatine more slender, with concave medial margin, Figs G-J), and the presence of a pronounced lateral process on the sesamoid supraorbital ( Fig. 11K ; vs absence, Figs G-J). Cambeva urubici n. sp. is also distinguished from C. duplimaculata n. sp. in having fewer dorsal procurrent caudal-fin rays (13-15, vs 16 or 17); and from C. longipalata n. sp. in having fewer vertebrae (40, vs 41 – 42), dorsal-fin origin in a vertical through the centrum of the 21st vertebra (vs 23rd or 24th) and anal-fin origin in a vertical through the centrum of the 25th vertebra (vs 26th).

DISTRIBUTION. — Cambeva urubici n. sp. occurs in the western open plateau. It is known from two localities in the upper Rio Canoas drainage, Rio Uruguai basin, in altitudes between about 910 and 940 m asl ( Fig. 14 ).

ETYMOLOGY. — The name urubici is an allusion to the occurrence of the species in the Rio Urubici, Rio Uruguai basin, southern Brazil, where is its type locality. This name is derived from theTupi-Guarani, but its meaning is unclear.

DESCRIPTION

General morphology

Morphometric data in Table 10 . Body moderately slender, subcylindrical anteriorly to compressed posteriorly. Greatest body depth in area just anterior to pelvic-fin base. Dorsal and ventral profiles of head and trunk slightly convex, approximately straight on caudal peduncle. Skin papillae minute. Anus and urogenital papilla in vertical trough anterior portion of dorsal-fin origin. Head trapezoidal in dorsal view, anterior profile of snout convex. Eye small, dorsally positioned in anterior half of head. Posterior nostril located nearer anterior nostril than orbital rim. Tip of maxillary barbel reaching anterior part of interopercular patch of odontodes; tip of rictal barbel reaching anterior margin of interopercular patch of odontodes, sometimes shorter, not reaching; tip of nasal barbel reaching posterior margin of orbit, or little beyond it. Mouth subterminal. Jaw teeth pointed, slightly curved, irregularly arranged, 46- 51 in both jaws. Branchial membrane attached to isthmus only at its anterior point. Branchiostegal rays 8 or 9. Cranial fontanels present, posterior fontanel long, anteriorly extending between frontals to reach transverse line close to lateral sphenotic process. Dorsal and anal fins short, subtriangular, distal margin slightly convex; total dorsalfin rays 12 (iii + II + 7), total anal-fin rays 10 (iii + I-II + 5-6); anal-fin origin in vertical just anterior to dorsal-fin base posterior end. Dorsal-fin origin in vertical through centrum of 21st or 22nd vertebra; anal-fin origin in vertical through centrum of 25th or 26th vertebra. Pectoral fin subtriangular in dorsal view, posterior margin slightly convex, first pectoral-fin ray not terminating in filament; total pectoral-fin rays 7 (I + 6). Pelvic fin subtruncate, its extremity in vertical through dorsal-fin origin; pelvic-fin bases medially in close proximity; total pelvic-fin rays 5 (I + 4). Caudal fin truncate, postero-dorsal and postero-ventral extremities rounded; total principal caudal-fin rays 13 (I + 11 + I), total dorsal procurrent rays 13-15 (xii-xiv + I), total ventral procurrent rays 10-11 (ix-x + I). Vertebrae 38-40. Ribs 15 or 16. Two dorsal hypural plates, corresponding to hypurals 4 + 5 and 3, respectively; single ventral hypural plate corresponding to hypurals 1 and 2 and parhypural.

Latero-sensory system

Supraorbital sensory canal continuous, connected to infraorbital sensory canal posteriorly. Supraorbital sensory canal with 3 pores: s1, adjacent to medial margin of anterior nostril; s3, adjacent to medial margin of posterior nostril; and s6, on middle part of dorsal surface of head, in transverse line just posterior to orbit; pore s6 nearer orbit than its paired homologous pore, near its paired homologous pore than orbit in larger specimens, above about 60 mm SL or more. Infraorbital sensory canal arranged in 2 segments, each with two pores; anterior segment with pore i1, in transverse line through anterior nostril, and pore i3, in transverse line just anterior to posterior nostril; posterior segment with pore i10, adjacent to ventral margin of orbit, and pore i11, posterior to orbit. Postorbital canal with 2 pores: po1, in vertical line above posterior portion of interopercular patch of odontodes, and po2, in vertical line above posterior portion of opercular patch of odontodes. Lateral line of body short, with 2 pores, posterior-most pore in vertical just posterior to pectoral-fin base.

Mesethmoidal region ( Fig. 11K )

Mesethmoid robust, its anterior margin about straight; mesethmoid cornu narrow, extremity rounded; narrow lateral flap on intersection between cornu and main bone axis, posteriorly extending parallel to lateral bone margin. Minute lateral projection on lateral ethmoid margin close to middle portion of sesamoid supraorbital. Antorbital thin, posteriorly supporting anterior infraorbital canal; sesamoid supraorbital flat, slender anteriorly, widening posteriorly, its length about twice or slightly less antorbital length, with pronounced lateral process postero-laterally directed. Premaxilla sub-trapezoidal in dorsal view, longer than maxilla. Maxilla boomerang-shaped, slender, slightly curved. Autopalatine sub-rectangular in dorsal view, robust, about so wide as long when excluding posterolateral process, medial margin straight to slightly concave, lateral margin nearly straight to slightly curved near posterolateral process; autopalatine posterolateral process subtriangular in dorsal view, with sharp extremity, short, its length shorter than osseus portion of autopalatine length excluding posterolateral process.

Cheek region ( Fig. 12J )

Metapterygoid thin, subtriangular, large, its largest length slightly longer than horizontal length of quadrate excluding dorsal process; short process just anterior to articulatory cartilaginous block. Quadrate slender, dorsal process with constricted base, dorsoposterior margin in contact with from hyomandibula outgrowth. Hyomandibula long, with well-developed anterior outgrowth; middle portion of dorsal margin of hyomandibula slightly concave. Opercle relatively slender, with deep transverse constriction just anterior to opercular odontode patch; opercular odontode patch depth about three fifths of dorsal hyomandibula articular facet, with 15 or 16 odontodes; odontodes pointed, straight to slightly curved, arranged in irregular transverse rows; dorsal process of opercle short and truncate; opercular articular facet for hyomandibula with small, rounded flap, articular facet for preopercle indistinct. Interopercle moderate, about two thirds hyomandibula length, anterior margin slightly concave; interopercular odontode patch with 18-20 pointed odontodes, arranged in irregular longitudinal rows. Preopercle compact, with short ventral flap.

Parurohyal ( Fig. 13J )

Robust, lateral process sub-triangular, posterior margin slightly sinuous, latero-posteriorly directed, extremity slightly pointed; parurohyal head well-developed, with prominent anterolateral paired process; middle foramen small, round; posterior process relatively long, about six tenths of distance between anterior margin of parurohyal and anterior insertion of lateral process.

Colouration in alcohol ( Fig. 10 )

Flank, dorsum and head side pale yellowish grey, with rounded dark brown spots; spots larger than interopercular patch of odontodes, arranged in three longitudinal series on flank; spots of two dorsal-most rows longitudinally coalesced with neighbouring spots in specimens about 50 mm SL or larger, forming stripe on longitudinal midlateral line of flank. Venter and ventral part of flank greyish white. Barbels dark grey. Fins pale grey. Smaller juvenile specimens, 23 mm SL or less, with homogeneous brownish grey flank; faint spots in juvenile specimens 25 mm SL or slightly larger.

Figures

FIG. 10. — Cambeva urubici n. sp., UFRJ 6967, holotype, 65.6 mm SL: A, left lateral view; B, dorsal view; C, ventral view.

FIG. 11. — Mesethmoidal region and adjacent structures, left and middle portions, dorsal view: A, Cambeva diffusa n. sp.; B, Cambeva pericoh n. sp.; C, Cambeva imaruhy n. sp.; D, Cambeva orbitofrontalis n. sp.; E, Cambeva panthera n. sp.; F, Cambeva grisea n. sp.; G, Cambeva duplimaculata n. sp.; H, Cambeva longipalata n. sp.; I, Cambeva notabilis n. sp.; J, Cambeva tropeira; K, Cambeva urubici n. sp. Larger stippling represents cartilaginous areas.

FIG. 12. — Left suspensorium and opercular series, lateral view: A, Cambeva diffusa n. sp.; B, Cambeva pericoh n. sp.; C, Cambeva imaruhy n. sp.; D, Cambeva orbitofrontalis n. sp.; E, Cambeva panthera n. sp.; F, Cambeva grisea n. sp.; G, Cambeva duplimaculata n. sp.; H, Cambeva longipalata n. sp.; I, Cambeva notabilis n. sp.; J, Cambeva urubici n. sp. Abbreviations of structures indicated by arrows are: iac, interopercular anterior concavity; ppe, preopercular postero-dorsal expansion; odc, opercular dorsal constriction; odp, opercular dorsal process; ppp, parurohyal posterior process.Larger stippling represents cartilaginous areas.

FIG. 13. — Urohyal, ventral view.A, Cambeva diffusa n. sp.; B, Cambeva pericoh n. sp.; C, Cambeva imaruhy n. sp.; D, Cambeva orbitofrontalis n. sp.; E, Cambeva panthera n. sp.; F, Cambeva grisea n. sp.; G, Cambeva duplimaculata n. sp.; H, Cambeva longipalata n. sp.; I, Cambeva notabilis n. sp.; J, Cambeva urubici n. sp.

FIG. 14. — Map of geographical distribution of Cambeva Katz, Barbosa, Mattos & Costa, 2018 in the southeastern nucleus of the Serra Geral (SESG), southern Brazil.