Cambeva duplimaculata, 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 : 675-678

Cambeva duplimaculata n. sp.

( Figs 7 , 11G , 12G , 13G ; Table 7)

urn:lsid:zoobank.org:act:17CCE793-8B84-41C6-B304-CD44C46747FE

MATERIAL EXAMINED. — Holotype. Brazil • 1 ex., 83.4 mm SL; Santa Catarina State: Bom Jardim da Serra Municipality : Rio Barrinha, a tributary of the upper Rio Pelotas , Rio Uruguai basin, 28°20’24”S, 49°36’59”W; about 1245 m asl; C. R. M. Feltrin; 8.II.2021; UFRJ 6949 .

Paratypes. Brazil • 2 ex., 29.6-61.5 mm SL; upper Rio Pelotas , Rio Uruguai basin, 28°20’07”S, 49°40’43”W; about 1190 m asl; C. R. M. Feltrin; 8.II.2021; UFRJ 6950 • 2 ex., 37.4-38.0 mm SL; same locality as UFRJ 6950; C. R. M. Feltrin; 16.VII.2020; UFRJ 6951 • 3 ex. (C&S), 33.5-41.1 mm SL; same data as UFRJ 6951; UFRJ 6952 .

DIAGNOSIS. — Cambeva duplimaculata n. sp. is distinguished from all other species of the C. tropeira complex in having more dorsal procurrent caudal-fin rays (16 or 17, vs 12-15) and a colour pattern in adult specimens (above about 50 mm SL) consisting of flank with rounded black spots arranged in three irregular longitudinal rows, overlapped by a high concentration of minute dark brown spots that are placed at a more superficial skin layer ( Fig. 7 ; vs never a similar colour pattern, Figs 8-10 ; see also Ferrer & Malabarba 2011: fig. 1). Also distinguished from C. longipalata n. sp. in having fewer vertebrae (39 or 40, vs 41 or 42), the dorsal-fin origin in vertical through centrum of 20th or 21st vertebrae (vs 23rd or 24th) and the anal-origin in vertical through centrum of 24th or 25th vertebrae (vs 26th), and a wider body (body width 10.8-11.8 % SL, vs 8.0-9.7 % SL); from C. notabilis n. sp. in having a shorter pelvic fin (pelvic-fin length 7.0-8.6 % SL, vs 9.0-10.4 % SL); from C. tropeira in having a well-developed pelvic fin (vs pelvic fin absent); from C. urubici n. sp. in having fewer teeth on premaxilla (38-41, vs 46-51) and dentary (35-39, vs 46-51); from C. notabilis n. sp., C. tropeira and C. urubici n. sp. in having more ventral procurrent caudal-fin rays (12-15, vs 10-11); and from C. notabilis n. sp. and C. urubici n. sp. in having fewer opercular odontodes (11-13, vs 15 or 16).

DISTRIBUTION. — Cambeva duplimaculata n. sp. occurs in the western open plateau. It is only known from two localities in the upper Rio Pelotas drainage, upper Rio Uruguai basin, in altitudes between about 1190 and 1250 m asl ( Fig. 14 ).

ETYMOLOGY. — The name duplimaculata , from the Latin (doubly maculated) refers to its colour pattern in the flank, consisting of two overlapped spotted patterns in different skin layers, comprising inner large black spots and outer small brown spots.

DESCRIPTION

General morphology

Morphometric data in Table 7. 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 through anterior third of dorsalfin base. 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 middle of interopercular patch of odontodes; tip of rictal and nasal barbels reaching anterior portion of interopercular patch of odontodes. Mouth subterminal. Jaw teeth pointed, slightly curved, irregularly arranged, 38-41 in premaxilla, 35-39 in dentary. Branchial membrane attached to isthmus only at its anterior point. Branchiostegal rays 9. Cranial fontanels present, posterior fontanel long, anteriorly extending between frontals to reach transverse line close to lateral sphenotic process. Dorsal and anal fins subtriangular, distal margin slightly convex; total dorsal-fin rays 12-13 (iii-iv + II + 7), total anal-fin rays 10-11 (iii-iv + II + 5); anal-fin origin in vertical through just anterior to posterior dorsal-fin base end. Dorsal-fin origin in vertical through centrum of 20th or 21st vertebra; anal-fin origin in vertical through centrum of 24th or 25th 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 anterior-most portion of dorsal-fin base; pelvic-fin bases medially in contact; total pelvic-fin rays 5 (I + 4). Caudal fin subtruncate, postero-dorsal and postero-ventral extremities rounded; total principal caudal-fin rays 13 (I + 11 + I), total dorsal procurrent rays 16-17 (xv-xvi + I), total ventral procurrent rays 12-15 (xi-xiv + I). Vertebrae 39-40. Ribs 14 or 15. 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. 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. 11G )

Mesethmoid robust, its anterior margin about straight; mesethmoid cornu narrow, extremity slightly pointed; 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 posterior portion of sesamoid supraorbital. Antorbital thin, posteriorly supporting anterior infraorbital canal; sesamoid supraorbital slender, its length about twice or slightly more antorbital length, sometimes with minute lateral process. Premaxilla sub-trapezoidal in dorsal view, slightly laterally narrowing, longer than maxilla. Maxilla boomerang-shaped, slender, slightly curved. Autopalatine sub-rectangular in dorsal view, moderate in width, longer than wide, lateral and medial margins slightly concave; 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. 12G )

Metapterygoid thin, subtriangular, large, its largest length about equal horizontal length of quadrate excluding dorsal process. 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 11-13 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 almost indistinct. Interopercle moderate, about two thirds hyomandibula length, anterior margin concave; interopercular odontode patch with 16-18 pointed odontodes, arranged in irregular longitudinal rows. Preopercle compact, with short ventral flap.

Parurohyal ( Fig. 13G )

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

Colouration in alcohol ( Fig. 7 )

Flank, dorsum and head side pale yellow, with rounded black spots, flank spots larger than interopercular patch of odontodes, head spots equal or slightly larger than orbit; flank spots arranged in three irregular longitudinal rows. Small pale brown spots in superficial skin layer, scattered over flank and dorsum, overlapping dark grey spots, their diameter equal or smaller than posterior nostril. Venter and ventral part of head greyish white. Barbels grey with dark grey margin. Fins pale grey with small black spots on basal portion.

Figures

FIG. 7. — Cambeva duplimaculata n. sp., UFRJ 6949, holotype, 83.4 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. 8. — Cambeva longipalata n. sp., UFRJ 6944, holotype, 86.0 mm SL: A, left lateral view; B, dorsal view; C, ventral view.

FIG. 9. — Cambeva notabilis n. sp., UFRJ 6965, holotype, 71.7 mm SL: A, left lateral view; B, dorsal view; C, ventral view.

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

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