Cambeva grisea, 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 : 673-675

Cambeva grisea n. sp.

( Figs 6 , 11F , 12F , 13F ; Table 6)

urn:lsid:zoobank.org:act:A5CFD65E-416F-4722-AE0B-9335C766E27F

MATERIAL EXAMINED. — Holotype. Brazil • 1 ex., 43.1 mm SL; Santa Catarina State: Treviso Municipality: village of Santo Antônio: Rio Pio , Rio Mãe Luzia drainage, Rio Araranguá basin; 28°29’17”S, 49°30’45”W; about 300 m asl; C. R. M. Feltrin; 30.XI.2020; UFRJ 6936 .

Paratypes. Brazil • 2 ex., 38.4-39.3 mm SL; collected with holotype; UFRJ 6937 • 4 ex., 29.1-40.9 mm SL (C&S); collected with holotype; UFRJ 6938 • 4 ex., 24.1-45.9 mm SL; same area as holotype, 28°29’32”S, 49°31’26”W; C. R. M. Feltrin; 29.IX.2018; UFRJ 1219 • 2 ex., 48.1-66.4 mm SL; same data as UFRJ 1219; CIC- CAA 04112 • 1 ex. (C&S), 52.3 mm SL; Siderópolis Municipality: stream tributary to Rio São Bento, village of São Pedro, Aguaí Santuário Ecológico; 28°36’52”S, 49°33’40”W; about 155 m asl; C. R. M. Feltrin; 26.VIII.2020; UFRJ 6962 • 4 ex. (C&S), 21.5- 34.8 mm SL; Siderópolis Municipality: Rio da Serra , about 100 m from the confluence with the Rio da Mina to form Rio São Bento, village of Costão da Serra ; 28°33’16”S, 49°34’53”W; about 230 m asl; C. R. M. Feltrin; 1.IX.2015; UFRJ 10698 .

DIAGNOSIS. — Cambeva grisea n. sp. is distinguished from C. brachykechenos , the only other species of the C. brachykechenos complex, in having more pleural ribs (13-15, vs 12), anal and dorsal fins more posteriorly placed relatively to vertebrae (dorsal-fin origin in a vertical through centrum of the 20th or 21st vertebra, vs 19th; anal-fin origin in vertical through centrum of 23rd or 24th vertebra, vs 21st or 22nd), and a different colouration on the flank (pale brownish grey, sometimes with dark grey pigment irregularly distributed, vs dark brown with small light brownish grey spots). Cambeva grisea n. sp. also seems to be smaller than C. brachykechenos , with the largest specimen found reaching only 52.3 mm SL (vs 70.9 mm SL recorded for C. brachykechenos by Ferrer & Malabarba 2013).

DISTRIBUTION. — Cambeva grisea n. sp. occurs in the eastern forested slope. It is known from the Rio Araranguá basin, in altitudes about 160-300 m asl ( Fig. 14 ).

ETYMOLOGY. — From the Latin grisea (grey), referring to the predominant colouration of this new species.

DESCRIPTION

General morphology

Morphometric data in Table 6. Body slender, subcylindrical and slightly depressed anteriorly, compressed posteriorly. Greatest body depth in area just anterior to pelvic-fin base. Dorsal profile of head and trunk slightly convex, approximately straight on caudal peduncle; ventral profile straight to slightly convex between lower jaw and end of anal-fin base, straight on caudal peduncle. Skin papillae minute. Anus and urogenital papilla in vertical just posterior to dorsal-fin origin. Head subtrapezoidal in dorsal view, almost rectangular, with anterior profile of snout slightly convex. Eye small, dorsally positioned in head, on its anterior half. Posterior nostril located nearer anterior nostril than orbital rim. Tip of maxillary and rictal barbels reaching area between interopercular patch of odontodes and pectoral-fin base; tip of nasal barbel reaching area between eye and opercular patch of odontodes. Mouth subterminal. Jaw teeth 26-35 in both jaws, incisiform in specimens above about 35 mm SL, pointed in smaller specimens, always irregularly distributed. Branchial membrane attached to isthmus only at its anterior point. Branchiostegal rays 8. Anterior cranial fontanel absent, posterior fontanel restricted to parieto-supraoccipital, sometimes slightly anteriorly ad - vancing between frontals. Dorsal and anal fins subtriangular, distal margin slightly convex; total dorsal-fin rays 11 (ii + II + 7), total anal-fin rays 9 (ii + II + 5); anal-fin origin in vertical through anterior third of dorsal-fin base. Dorsal-fin origin in vertical through centrum of 20th or 21st vertebra; anal-fin origin in vertical through centrum of 23rd or 24th vertebra. Pectoral fin subtriangular in dorsal view, posterior margin slightly convex, first pectoral-fin ray not terminating in filament; total pectoral-fin rays 6 (I + 5). Pelvic fin subtruncate, its extremity in vertical anterior to 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 14-16 (xiii-xv + I), total ventral procurrent rays 8-12 (vii-xi + I). Vertebrae 38-39. Ribs 13-15. Single dorsal hypural plate, corresponding to hypurals 3 + 4 + 5, single ventral hypural plate corresponding to hypurals 1 + 2 and parhypural.

Latero-sensory system

Supraorbital sensory canal continuous, connected to posterior section of infraorbital canal posteriorly. Supraorbital sensory canal with 3 pores: s1, adjacent to medial margin of anterior nostril; s3, adjacent and just posterior to medial margin of posterior nostril; and s6, in transverse line through posterior half of orbit; pore s6 nearer orbit than its paired homologous pore. Single infraorbital sensory canal segment, with two pores, corresponding to pore i10, adjacent to ventral margin of orbit, and pore i11, posterior to orbit; anterior segment of infraorbital canal absent. 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. 11F )

Mesethmoid robust, its anterior margin about straight; mesethmoid cornu subtriangular in dorsal view, extremity pointed; narrow lateral flap on intersection between cornu and main bone axis. Small lateral projection on lateral ethmoid margin close to middle portion of sesamoid supraorbital. Antorbital thin, drop-shaped; sesamoid supraorbital short and slender, slightly longer than antorbital, without processes. Premaxilla sub-trapezoidal in dorsal view, laterally narrowing, moderate in length, slightly longer than maxilla. Maxilla boomerangshaped, slender, slightly curved. Autopalatine sub-rectangular in dorsal view, medial margin slightly concave, lateral margin approximately straight; autopalatine posterolateral process short, subtriangular.

Cheek region ( Fig. 12F )

Metapterygoid thin, subtrapezoidal, large, slightly longer than deep, its largest length about equal to horizontal length of quadrate excluding dorsal process. Quadrate slender, dorsal process with constricted base, dorsoposterior margin separated from hyomandibula outgrowth by small interspace. Hyomandibula long, with well-developed anterior outgrowth; middle portion of dorsal margin of hyomandibula slightly concave. Opercle relatively slender, opercular odontode patch depth about half length of dorsal hyomandibula articular facet, with 10-16 odontodes; odontodes pointed, nearly straight to slightly curved, arranged in irregular transverse rows; dorsal process of opercle short and pointed; opercular articular facet for hyomandibula with prominent trapezoidal flap, articular facet for preopercle inconspicuous. Interopercle moderate, its length about equal to hyomandibular outgrowth length, with 23-26 odontodes; odontodes pointed, arranged in irregular longitudinal rows. Preopercle compact, with short ventral flap.

Parurohyal ( Fig. 13F )

Parurohyal robust, lateral process sub-triangular, slightly curved, latero-posteriorly directed, extremity pointed; parurohyal head well-developed, with anterolateral paired process; middle foramen oval; posterior process short, about one third of distance between anterior margin of parurohyal and anterior insertion of posterior process.

Colouration in alcohol ( Fig. 6 )

Flank pale brownish grey, sometimes with dark grey pigment irregularly distributed; dorsum greyish brown with small light grey vermiculate spots, venter light yellowish grey. Head pale brownish grey to brown on nape, with darker pigmentation concentrated between orbit and anterior nostril; small dark grey spots along lateral extremity of head and basal portion of barbels. Fins whitish hyaline, with minute grey dots along rays of unpaired fins and small dark grey spot close to dorsal-fin origin and pectoral-fin base.

Figures

FIG. 6. — Cambeva grisea n. sp., UFRJ 6936, holotype, 43.1 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.