Cyphocharax tamuya, Dutra & Vita & Gentile & Ochoa & Netto-Ferreira, 2022

Dutra, Guilherme Moreira, Vita, George, Gentile, Péricles Vinícius, Ochoa, Luz Eneida & Netto-Ferreira, Andre Luiz, 2022, Integrative taxonomy reveals a new species of Cyphocharax (Characiformes: Curimatidae) from the Upper Paraíba do Sul River basin, Brazil, Neotropical Ichthyology (e 220017) 20 (3), pp. 1-17 : 5-11

Cyphocharax tamuya , new species urn:lsid:zoobank.org:act:DF3AFC11-26F6-4F99-8F99-D32390195637

( Figs. 1 , 2A,B ; Tab. 2)

Cyphocharax gilbert (non Quoy, Gaimard). —Vari, 1992:93 (analyzed specimens from Paraibuna River).

Holotype. MZUSP 125833, 106.8 mm SL, Paraibuna River, Paraibuna , São Paulo,

Brazil, 23°22’59”S 45°40’00”W, 19 May 1977, I. Sazima, U. Caramaschi & D. S. Rocha .

Paratypes. All from Brazil, São Paulo, Paraíba do Sul River basin: MZUSP 21668 (3, 87.9–106.8 mm SL), collected with holotype. MZUSP 20686 (5, 83.6–97.9 mm SL), Córrego do Rogero , Santa Branca , ca. 23°22’S 45°44’W, 22 Jan 1961, H. A. Britski. MZUSP 20687 (1, 87.4 mm SL), Córrego do Rogero , Santa Branca , ca. 23°22’S 45°44’W, 14 Jan 1961, H. A. Britski. MZUSP 20729 (3, 88.2–89.9 mm SL), Córrego do Rogero , Santa Branca , ca. 23°22’S 45°44’W, 16 Sep 1962, H. A. Britski & J. Rossi. MZUSP 43822 (5+1 CS, 74.1–113.6 mm SL), Paraibuna River , Paraibuna, 23°25’59”S 45°17’59”W, 22 Apr 1992, R. S. Lima. MZUSP 108111 (4+1 CS, 64.0– 164.5 mm SL), Paraitinga River , São Luiz do Paraitinga , 23°13’34”S 45°20’26”W, 15 Jun 2010, CESP-Paraibuna & ICMBio staffs. MZUSP 108117 (2, 68.5–79.1 mm SL), Paraitinga River , São Luiz do Paraitinga , 23°14’57”S 45°18’49”W, 16 Jun 2010, MZUSP team, CESP-Paraibuna & ICMBio staffs. MZUSP 126668 (5, 155.5– 196.2 mm SL), MZUSP 126669 (4, 176.5– 178.5 mm SL), Paraibuna dam, below Capim de Angola, Paraibuna, 23°33’50”S 45°35’00”W, 22 Aug 2021, G. Dutra & G. Vita .

Diagnosis. Cyphocharax tamuya differs from most congeners, except C. aninha Wosiacki & Miranda, 2014 , C. gilbert , C. gillii (Eigenmann & Kennedy, 1903) , C. gouldingi Vari, 1992 , C. meniscaprorus Vari, 1992 , C. mestomyllon Vari, 1992 , C. modestus (Fernández-Yépez, 1948) , C. naegelii (Steindachner, 1881) , C. oenas Vari, 1992 , C. platanus (Günther, 1880) , C. santacatarinae (Fernández-Yépez, 1948) , C. spilotus (Vari, 1987) , C. spiluropsis (Eigenmann & Eigenmann, 1889) , and C. spilurus (Günther, 1864) by the absence of distinctive pigmentation of the body and fins combined with a dark blotch on the midlength of the caudal peduncle [vs. possession of a reticulate color pattern formed by pigmentation on the scale borders plus a round dark blotch on the caudal peduncle in C. gangamon Vari, 1992 ; a longitudinal series of dark blotches on the scales of the flanks plus a caudal peduncle blotch extending from the base of the median caudal-fin rays to the vertical through the posterior limit of the adipose-fin base in C. sanctigabrielis ; multiple series of dark stripes or spots running between most scale rows in C. cramptoni Bortolo & Lima, 2020 , C. helleri (Steindachner, 1910) , C. multilineatus (Myers, 1927) , and C. pantostictos Vari & Barriga Salazar, 1990 ; a patch of dark pigmentation on the dorsal fin in C. notatus (Steindachner, 1908) and C. vexillapinnus Vari, 1992 ; a single dark midlateral stripe in C. boiadeiro Melo, 2017 , C. corumbae , C. laticlavius Vari & Blackledge, 1996 , C. saladensis (Meinken, 1933) , and C. signatus Vari, 1992 ; a midlateral series of irregular patches of dark pigmentation along the lateral line in C. albula , C. jagunco , C. punctatus (Vari & Nijssen, 1986) , and C. vanderi (Britski, 1980) ; a random pattern of small dark spots on the lateral and dorsolateral surfaces of the body in C. voga (Hensel, 1870) ; a midlateral spot of dark pigmentation ventral to the dorsal-fin base in C. biocellatus Vari, Sidlauskas & Le Bail, 2012 ; or the lack of a pronounced caudal-peduncle blotch in C. abramoides (Kner, 1858) , C. aspilos Vari, 1992 , C. derhami Vari & Chang, 2006 , C. festivus Vari, 1992 , C. leucostictus (Eigenmann & Eigenmann, 1889) , C. magdalenae , C. microcephalus (Eigenmann & Eigenmann, 1889) , C. muyrakytan Bortolo, Lima & Melo, 2018 , C. nigripinnis Vari, 1992 , C. pinnilepis , C. plumbeus (Eigenmann & Eigenmann, 1889) , and C. stilbolepis Vari, 1992 ]. Cyphocharax tamuya can be distinguished from most congeners with a dark blotch on the caudal peduncle, except C. naegelii , by the presence of 19–20 circumpeduncular scales [vs. 16– 18 in C. gilbert (n = 43), and 16 in C. modestus (n = 3), C. santacatarinae (n = 10), C. spilotus (n = 8), C. voga (n = 11), and 23–25 in C. platanus (n = 9)]. It differs from C. naegelii by possessing a round caudal peduncle blotch that does not reach the proximal portions of the median caudal-fin rays [vs. a horizontally elongate blotch that extends onto the median caudal-fin rays ( Fig. 2 )], the greatest body depth corresponding to 34.7–39.9% of SL (vs. 29.0–33.0% of SL), the caudal peduncle depth corresponding to 13.3–15.2% of SL (vs. 12.0–13.0% of SL), and the presence of 33 vertebrae (vs. 34). The new species differs from C. platanus by the presence of 34–41 pored lateral-line scales from the supracleithrum to the hypural joint (vs. 48–54), and the presence of 6–7 scale rows between the lateral-line scale series and the anal-fin origin (vs. 8–10). Furthermore, the new species differs from C. voga by the presence of 33 vertebrae (vs. 34–37), from C. santacatarinae by the presence of 6–7 scale rows between the lateral-line scale series and anal-fin origin (vs. 4–5), and from C. spilotus by the presence of 34–41 pored lateral-line scales from the supracleithrum to the hypural joint (vs. 29–33).

Description. Morphometric data for holotype and 24 paratypes presented in Tab. 2. Body somewhat elongate. Greatest body depth at vertical through dorsal-fin origin. Dorsal profile of head strongly convex from margin of upper lip to vertical through anterior nostril, slightly concave to nearly straight from that point to supraoccipital spine. Dorsal profile of body slightly convex from that point to dorsal-fin terminus; nearly straight from that point to adipose-fin origin and then slightly concave to origin of anteriormost dorsal caudal-fin procurrent ray. Ventral profile of body convex from lower lip to anal-fin terminus; concave from that point to origin of anteriormost ventral caudal-fin procurrent ray. Prepelvic region smoothly flattened transversely. Postpelvic region of body transversely round.

Head compressed, pointed overall in lateral view. Mouth subterminal, located at horizontal through ventral margin of pupil. Upper jaw slightly longer than lower jaw. Nostrils close together and separated by thin flap of skin. Anterior nostril circular, near midpoint between snout tip and anterior margin of eye. Posterior nostril crescent shaped. Adipose eyelid more developed anteriorly, with vertically ovoid opening near center of eye. Eye on anterior one-half of head length. Branchial membranes joined at isthmus. Branchiostegal rays 4(2).

Scales cycloid. Lateral-line series with 34(1), 36(5), 37(9), 38*(7), 39(2) or 41(1) perforated scales from supracleithrum to hypural joint; perforated scales posterior to hypural joint 1(2), 2*(13), 3(8) or 4(1) [zero in one specimen]. Scale rows between dorsal-fin origin and lateral line 6*(11) or 7(14). Scale rows between anal-fin origin and lateral line 6*(12) or 7(13). Scales between anus and anal-fin origin 2*(20) or 3(5). Predorsal scales 11(2), 12(1), 13*(14), 14(7) or 16(1). Circumpeduncular scales 19(3) or 20*(22). Scales covering basal portion of caudal-fin rays distinctly smaller than those on caudal peduncle.

Pectoral fin pointed, with i,12(5), 13*(12), 14(7) or 15(1) rays; tip of adpressed pectoral fin reaching vertical between eighth to tenth lateral line scale. Supraneurals 5(2), first and second inserted immediately anterior to neural spine of 5 th vertebra. Dorsal fin pointed, with ii,9*(24) or 10(1) rays; first unbranched ray about one-half length of second unbranched ray, second unbranched and first branched rays longest; branched rays gradually decreasing in length posteriorly. Dorsal-fin pterygiophores 11(2); first inserted immediately posterior to neural spine of 9 th (2) vertebra. Pelvic fin emarginate, with i,8*(25) rays; fin origin at vertical through third or fourth branched dorsal-fin ray. Tip of adpressed pelvic fin falling short of anus by 1*(6), 2(12) or 3(5) scales. Anal fin emarginate, with ii,7*(25) rays; first unbranched ray about one-third length of second unbranched ray; second unbranched ray and first branched rays longest, subsequent branched rays gradually decreasing in length. Anal-fin pterygiophores 8(1) or 9(1); first inserted immediately posterior to haemal spine of 23 rd (2) vertebra. Adipose fin present. Caudal fin with i,9/8,i*(25) rays; forked with lobes somewhat pointed. Dorsal procurrent rays of caudal-fin 8(2); ventral procurrent rays of caudal-fin 5(2). Total vertebrae 33(2). Precaudal vertebrae 20(1) or 21(1), caudal vertebrae 12(1) or 13(1).

Coloration in alcohol. Specimens retain silvery guanine deposits on infraorbitals and opercular series. Background coloration of body tan. Dark coloration on dorsal portion of head, maxilla, upper lip and infraorbital 1, lighter ventrally. Dark chromatophores on postorbital region of head slightly larger than those on snout. Overall pigmentation of latter portion of postorbital region consequently lighter than adjoining surrounding areas. Scale rows from predorsal to lateral-line series with dark chromatophores concentrated at focus of each scale. Scales below lateral line with few, sparse chromatophores, lacking distinctive pigmentation pattern. Lateral surface of body of small specimens (up to 69.7 mm SL; Fig. 2B ) with faint dark midlateral stripe up to 2 scales deep running from vertical through dorsal-fin insertion to anterior margin of caudal peduncle blotch. Dark midlateral stripe inconspicuous or absent in specimens larger than 70 mm SL. Midlateral surface of caudal peduncle with dark round blotch, not extending onto proximal portions of median caudal-fin rays. Caudal peduncle blotch more conspicuous in juveniles ( Fig. 2B ). Distal tip of dorsal fin with discrete, dark chromatophores on rays and associated membranes. Anal-fin rays with dark chromatophores on distal tip, more concentrated on anteriormost rays. Adipose, caudal, pectoral and pelvic fins overall hyaline. Caudal fin with discrete dark chromatophores more concentrated on lower caudal-fin lobe in some specimens.

Geographical distribution. Cyphocharax tamuya is known from the Paraíbuna and Paraitinga rivers, two main headwater tributaries of the Paraíba do Sul River, São Paulo, Brazil ( Fig. 3 ).

Etymology. The epithet “tamuya ” honours the indigenous Tamuya people. The word Tamuya, from Tupinambá language, means “grandfather or the oldest”. Linguistics variations to Tamuya include “Tamúya”, “Tamujas” or “Tamuía”, all keeping the same origin and meaning. The Tamuyas were driven extinct during the colonization of the Brazilian coast in the seventeenth century. Before their extinction, they lived in the area of occurrence of Cyphocharax tamuya . A noun in apposition.

Conservation status. The Upper Paraíba do Sul River basin area was impacted in the

1970’s by the construction of the Paraibuna Dam, which changed the water dynamics in the area. However, considering that Cyphocharax species inhabit lentic waters, the dam may not impact the population of C. tamuya in that area. In fact, part of the specimens examined herein originate from inundation zone above the dam and were collected after the dam’s construction (e.g., MZUSP 21668). Furthermore, the species also occurs in at least three localities upstream of the dam. Thus, we recommend that C.

tamuya be classified as Least Concern (LC), according to the International Union for

Conservation of Nature (IUCN) categories and criteria (IUCN Standards and Petitions

Subcommittee, 2019).

Molecular species delimitation. The molecular dataset included 210 sequences of

657 base pairs in length. Stop codons, deletions or insertions were not observed in any sequences. In the matrix 386 positions were conserved and 271 were variable, with base compositions of 23% adenine, 27.9% cytosine, 30.1% thymine and 18.4% of guanine.

The data were not saturated as evaluated via the Iss.c value. The maximum likelihood tree from RAxML shows the same topology obtained in the ultrametric tree from BEAST and the three delimitation analyses ( Fig. 4 ). The bPTP approach delimited 95 lineages, and

Cyphocharax tamuya was grouped with the remaining species composing the C. gilbert clade of Melo et al. (2018) with a posterior probability of 0.926 ( Fig. 5 ). In contrast, the results from the ASAP analysis showed a low asap score of 4.00 with a p-value 0.0063,

and delimited 101 species from the total dataset (six more than did bPTP). The ASAP analysis delimited all species belonging to the C. gilbert clade as unique lineages except for C. naegelii and C. platanus which were grouped in a single lineage. The best fitting model in the GMYC analysis received a likelihood score of 1471.86 in comparison with the null model of 1435.10. The GMYC analysis identified a total of 106 entities with a confidence interval of 103-111 and a threshold time of -0.007. This analysis recognized the new species as a differentiated entity, again grouped C. naegelii and C. platanus in the same lineage, and recovered two distinct lineages within C. modesus . Regarding the genetic distances from a sub-matrix containing the COI sequences from the all known species in C. gilbert clade ( Tab. 3), the overall mean distance among species was 3%. The lowest genetic distance between C. tamuya and any other known species was 2.5% (from C. gilbert ), followed by 3% from C. santacatarinae , and 3.2% from C. aff. gilbert .

Figures

FIGURE 1 | Lateral view of Cyphocharax tamuya. A. MZUSP 125833, holotype, 106.8 mm SL, Paraibuna River, Paraíba do Sul River basin, São Paulo, Brazil; B. MZUSP 108117, paratype, 69.7 mm SL, Paraitinga River, Paraíba do Sul River basin, São Paulo, Brazil.

FIGURE 2 | Caudal peduncle and fin of Cyphocharax species: A. C. tamuya, MZUSP 108117, paratype; B. C. voga, MZUSP 39782; C. C. santacatarinae, MZUSP 58659; D. C. gilbert, MZUSP 26861; E. C. naegelii, MZUSP 207752; F. C. platanus, MZUSP 45858.

FIGURE 3 | Map of eastern portion of South America showing the type locality (star) and distribution of Cyphocharax tamuya. Symbols may represent more than one collection event.

FIGURE 4 | Maximum likelihood tree of Curimatidae using COI (210 sequences with 657 bp) depicting the Cyphocharax gilbert clade (black dot). Numbers at right of nodes represent bootstrap support.

FIGURE 5 | Results of the molecular delimitations methods bPTP, ASAP and GMYC for the species included in the Cyphocharax gilbert clade. MOTUs are represented by black rectangles.