Cambeva longipalata, 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 : 678-680

Cambeva longipalata n. sp.

( Figs 8 , 11H , 12H , 13H ; Table 8)

urn:lsid:zoobank.org:act:F938318C-424E-490E-B187-3CBEBD09F201

MATERIAL EXAMINED. — Holotype. Brazil • 1 ex., 86.0 mm SL; Santa Catarina State: Bom Jardim da Serra Municipality: Rio Mantiqueira, tributary of Rio Pelotas , Rio Uruguai basin; 28°15’47”S, 49°45’46”W; about 1325 m asl; C. R. M. Feltrin; 8.II.2021; UFRJ 6944 .

Paratypes. Brazil • 6 ex., 26.5-53.9 mm SL; collected with holotype; UFRJ 6945 • 1 ex. (C&S), 52.4 mm SL; collected with holotype; UFRJ 6947 • 2 ex., 46.4-52.9 mm SL; collected with holotype; CICCAA 04109 • 11 ex., 28.5-37.03 mm SL; same area as holotype, 28°16’08”S, 49°45’40”W; about 1325 m asl; C. R. M. Feltrin; 16.VII.2020; UFRJ 6946 • 4 ex. (C&S), 28.9-36.9 mm SL; same data as UFRJ 6946; UFRJ 6948 .

DIAGNOSIS. — Cambeva longipalata n. sp. differs from all other congeners of the C. tropeira complex in having more vertebrae (41 or 42, vs 37-40), dorsal-fin origin in a vertical between the centrum of the 23rd or 24th vertebra (vs 19th–21st) and anal-fin origin in a vertical between the centrum of the 26th vertebra (vs 22nd– 25th), a narrower body (body width 8.0-9.7 % SL, vs 10.0-12.8 % SL); and a long posterolateral process of the autopalatine, its length about equal to the osseus portion of the autopalatine length excluding the posterolateral process ( Fig. 11H , vs smaller, Figs 11G , I-K). Cambeva longipalata n. sp. is distinguished from all other congeners of the C. tropeira complex, except C. tropeira , in having rounded black spots and dots irregularly arranged on the flank (never a similar colour pattern), and the presence of a lateral projection on the lateral ethmoid, close to the middle portion of the sesamoid supraorbital ( Figs 11H, J ; vs projection absent or close to posterior portion of the sesamoid supraorbital when present, Figs 11 G, I, K ) and posterior portion of the antorbital slightly laterally bowed ( Fig. 11H, J ; vs straight, Figs 11 G, I, K ); C. longipalata n. sp. is readily distinguished from C. tropeira in having a well-developed pelvic fin (vs pelvic fin absent). Cambeva longipalata n. sp. is also distinguished from C. duplimaculata n. sp. in having fewer dorsal procurrent caudalfin rays (12-14, vs 16 or 17); from C. urubici n. sp. in having fewer teeth in the premaxilla (39 – 41, vs 46-51) and dentary (35-38, vs 46-51); and from C. notabilis n. sp. and C. urubici n. sp. in having fewer opercular odontodes (10 or 11, vs 14-16).

DISTRIBUTION. — Cambeva longipalata n. sp. occurs in the western open plateau. It is only known from the Rio Mantiqueira, a tributary of the upper Rio Pelotas, upper Rio Uruguai basin, about 1330 m asl ( Fig. 14 ).

ETYMOLOGY. — From the Latin, the name longipalata (long palate) is an allusion to the peculiar morphology of the autopalatine of the new species, with a long posterolateral process.

DESCRIPTION

General morphology

Morphometric data in Table 8. 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 just posterior to 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 between interopercular and opercular patch of odontodes; tip of nasal and rictal barbels reaching interopercular patch of odontodes. Mouth subterminal. Jaw teeth pointed, slightly curved, irregularly arranged, 39-41 in premaxilla, 35-38 in dentary. Branchial membrane attached to isthmus only at its anterior point. Branchiostegal rays 8. 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 dorsalfin rays 12 (iii + II + 7), total anal-fin rays 10 (iii + I-II + 5-6); anal-fin origin in vertical through middle of dorsalfin base or just posterior to it. Dorsal-fin origin in vertical through centrum of 23rd or 24th vertebra; anal-fin origin in vertical through centrum of 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 anterior to dorsal-fin base; 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 12-14 (x-xiii + I-II), total ventral procurrent rays 10-12 (xi-xv + I). Vertebrae 41-42. Ribs 13 or 14. Two dorsal hypural plates, corresponding to hypurals 4 + 5 and 3, respectively, often coalesced to form single plate; 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. 11H )

Mesethmoid robust, its anterior margin about straight; mesethmoid cornu narrow, extremity 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 middle portion of sesamoid supraorbital. Antorbital thin, posterior portion slightly laterally bowed, posteriorly supporting anterior infraorbital canal; sesamoid supraorbital slender, its length about twice or slightly less antorbital length, with weak lateral projection. Premaxilla sub-trapezoidal in dorsal view, slightly laterally narrowing, longer than maxilla.Maxilla boomerang-shaped, slender, slightly curved. Autopalatine sub-rectangular in dorsal view, slender, longer than wide, with posterior portion of medial margin expanded, lateral margin nearly straight to slightly curved near posterolateral process; autopalatine posterolateral process subtriangular in dorsal view, with sharp extremity, long, its length about equal to osseus portion of autopalatine length excluding posterolateral process.

Cheek region ( Fig. 12H )

Metapterygoid thin, subtriangular, large, its largest length slightly longer than horizontal length of quadrate excluding dorsal process; minute 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 10 or 11 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. 13H )

Robust, lateral process sub-triangular, posterior margin slightly sinuous, latero-posteriorly directed, extremity pointed; parurohyal head well-developed, with 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. 8 )

Flank, dorsum and head side pale yellow, with rounded black spots and small dots; most flank spots larger than interopercular patch of odontodes, head spots equal or slightly larger than orbit; spots and dots irregularly arranged on flank. Venter and ventral part of flank greyish white. Barbels dark grey. Fins pale grey with small, dark greyish brown spots on basal portion.

Figures

FIG. 8. — Cambeva longipalata n. sp., UFRJ 6944, holotype, 86.0 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.