Hyphessobrycon uaiso : new characid fish from the rio Grande , upper rio Paraná basin , Minas Gerais State ( Ostariophysi : Characidae ) , with a brief comment about some types of Hyphessobrycon

Hyphessobrycon uaiso is described from the upper rio Paraná basin, rio Grande drainage, Minas Gerais State. The new species differs from its congeners by the short anal fin with 12-17 branched rays, and dorsal fin with ii,7-8 rays. Besides, it can be distinguished by the presence of i,5-6 pelvic fin rays, and by the coloration of the eyes (in life), slightly blue on the lower half and blackish on the upper half. New records of Hyphessobrycon are recognized for the upper rio Paraná basin: H. eilyos Lima & Moreira, H. guarani Mahnert & Géry, and H. herbertaxelrodi Géry. The knowledge status about the ichthyofauna from the upper rio Paraná basin and comments about the type material of some species of Hyphessobrycon are briefly discussed.


Introduction
Hyphessobrycon Durbin is one of richest genus of Characidae, with approximately 130 valid species, widely distributed on the Neotropical region from Mexico to Argentina (Eschmeyer, 2013).Since the genus was proposed by Durbin (1908) [in Eigenmann, 1908] more than one century ago, few proposals for inter-and intra relationships within Hyphessobrycon were suggested.Current phylogenetic hypotheses to Characidae (Mirande, 2009(Mirande, , 2010morphological analysis;morphological analysis;Oliveira et al., 2011 -molecular analysis), which encompass some species of Hyphessobrycon, failed to include its type species, Hyphessobrycon compressus Meek.Malabarba et al. (2012), in the revalidation of Ectrepopterus Fowler, previously considered a synonym of Hyphessobrycon, analyzed its relationships in the Mirande's (2010) Characidae context, and also included H. compressus for the first time in a phylogenetic analysis.The results (Mirande, 2009(Mirande, , 2010;;Malabarba, 2012), clearly showed that the genus Hyphessobrycon is not monophyletic and its type species is not close related to some species of Hyphessobrycon [e.g.H. anisitsi (Eigenmann), H. bifasciatus Ellis, H. elachys Weitzman, H. herbertaxelrodi Géry, H. luetkenii (Boulenger)], but to some taxa belonging to the putative 'rosy tetra clade' of Weitzman & Palmer (1997), such as H. eques (Steindachner), H. pulchripinnis (Ahl), H. socolofi (Weitzman), and Hemigrammus unilineatus (Gill).One of the characters supporting the monophyly of this group is the presence of a dark conspicuous spot on the dorsal fin, as suggested by Weitzman & Palmer (1997).This result partially answered the question raised by Lucena (2003) about the relationships of H. compressus with its congeneric species.Despite this initial evidence, there is not a robust proposal for the relationships within the genus Hyphessobrycon, which continues to be diagnosed by the combination of nonexclusive characters first presented by Eigenmann (1917): lateral line incomplete; premaxillary teeth in two series, the inner series with five teeth; second suborbital (= third infraorbital sensu Weitzman, 1962) not in contact with the preopercle ventrally; few maxillary teeth; caudal fin naked, and adipose fin present.
The new species described herein is not a member of the genus Hyphessobrycon sensu stricto (which includes those species related to the type species), but presents the traditional diagnostic characters proposed by Eigenmann (1917Eigenmann ( , 1918)).Due to the urgency for the description of new taxa of Neotropical fishes whose habitats are facing increasing and deleterious anthropogenic changes, we herein describe this new species in the traditional concept of the genus Hyphessobrycon until the proposal of the relationships of the genus, an ongoing study by the senior author, is presented.Fink & Weitzman (1974), Lima &Moreira (2003), andCarvalho et al. (2010).Measures were made with a caliper rule to the nearest 0.05 mm on the left side of the specimen whenever possible, and are presented as percents of standard length (SL) or head length (HL).In the description, counts are followed by their frequency in parentheses, and an asterisk indicates the count of the holotype.In the list of paratypes and material examined, the number of all specimens in the lot is followed by the number of those examined and cleared and stained (c&s) individuals, if any.Counts for vertebrae, supraneurals, gill-rakers on the first branquial arch, branchiostegal rays, procurrent caudal-fin rays, and small dentary teeth were taken from six c&s specimens prepared according to Taylor & Van Dyke (1985).Vertebral count includes the four vertebrae in the Weberian apparatus and the fused PU1+U1 of the caudal region as a single element.The pattern of circuli and radii was defined on scales sampled from the region between the lateral line and the insertion of pelvic-fin.Comparisons and data of species not available for examination were taken from the literature.Catalog numbers are followed by the total number of specimens, number of specimens measured and counted in parentheses, and SL range of all specimens of the lot.

Measurements and counts follow
Comparative material examined include the most valid species of Hyphessobrycon.For the type material herein analyzed, including some junior synonyms of Hyphessobrycon species and other genera, the names are listed according to the original description; see also Carvalho et al. (2010) for additional examined Characidae taxa.
Description.Morphometric data are presented in Table 1.Body compressed, moderately short, greatest body depth at vertical through dorsal-fin origin or straightway after.Dorsal profile of head convex from tip of upper jaw to vertical through anterior nostril; slightly straight or concave from that point to tip of supraoccipital spine.Dorsal profile of body slightly convex from posterior tip of supraoccipital spine to base of last dorsal-fin ray, and straight to adipose-fin origin.Ventral profile of body convex from tip of lower jaw to pelvic-fin origin, straight or slightly convex from that point to anal-fin origin, and straight and/or subtly rounded along anal-fin base.Dorsal and ventral profile of caudal peduncle slightly straight.Eyes moderate, without distinct adipose eyelid.Jaws equal in size, mouth terminal.Maxilla extending posteriorly surpassing anterior margin of orbit until vertical through crystalline lens anterior margin, slightly curved, aligned approximately at 45 degrees angle relative to longitudinal axis of body.Nostrils close to each other, anterior opening small and circular, posterior one twice in size and slightly reniform or elongate.Nostrils separated by skin flap.Frontals united anteriorly or not, with a triangle-shaped fontanel; parietal fontanel large, extending from epiphyseal bar to supraoccipital spine.Infraorbital series with five or six elements, fourth infraorbital reduced dorsally (triangle-shaped), rectangular, or fusioned with fifth infraorbital.Laterosensorial canal from first to sixth infraorbital close to inner margin of orbital rim.Third infraorbital largest, double size of others (in length and depth), contacting laterosensory canal of preopercle ventrolaterally.

Color in alcohol.
Overall body color yellowish to brownish.Body scales slightly reticulated, especially on anterior portion of scales.Head dusky to dark brown dorsally.Region of infraorbitals and opercle with small chromatophores, scattered uniformly, except on upper and posterior region with more concentration of spots.Top of head, from lips to supraoccipital process blackish, with high concentration of chromatophores.Humeral spot conspicuous, origin just after opercular opening and extending through five or six transversal scale series, vertically elongated on young specimens (up to 34 mm SL) and approximately vertically rounded on adults (larger than 34 mm SL).When vertically rounded, spot extending through five or six horizontal scale series, above lateral line; on young specimens (up to 32.4 mm), humeral spot slender ventral to lateral line.Lateral side of body with scattered melanophores except at abdominal region.Longitudinal stripe dark, one or one-half scale wide, extending from vertical through middle of pectoral fin, passing through end of caudal peduncle end, extending onto proximal one-third of middle caudal-fin rays.Longitudinal stripe more conspicuous posterior to vertical through middle of dorsal-fin base.Caudal peduncle spot merged to longitudinal stripe.Fins darkish, with scattered melanophores on rays and interradial membrane.Color in life.Overall body and head color pattern yellowish, slightly brown (Fig. 3).Pattern of melanophores distribution on head, body and fins similar to that described for specimens in alcohol.Dorsal, caudal, pelvic, and pectoral fins with anterior portion yellowish and posterior reddish.Adipose fin yellowish.Longitudinal stripe more conspicuous along caudal peduncle.Color pattern of eyes composed by slightly blue coloration on lower half and blackish on upper half of iris, on males and females (Fig. 3b).
Sexual dimorphism.The mature males and females of Hyphessobrycon uaiso, confirmed by visual and histological analyses, do not present bony hooks on fins.No difference (morphological or color pattern) was found between males and females.Also, gill glands (Burns & Weitzman, 1996) were not found macroscopically on first gill arch on both sexes.
Distribution.Hyphessobrycon uaiso is known from rio Uberaba, rio Grande drainage, upper rio Paraná basin (Fig. 4).The upper rio Paraná basin is a well sampled Neotropical basin (Langeani et al., 2007), and even though the upper rio Paraná basin can be considered a well sampled hydrographic system, we are unable to locate any additional samples of the species in the fish collections that hold most material from this river system.
Etymology.The specific name, uaiso, of Portuguese "uai sô", is a common colloquial interjection used by most people living in Minas Gerais State, Brazil, to express surprise, confirmation, awe, amazement, in special those from the "Triângulo Mineiro", region where the new species was found.A name in apposition.
Ecological notes.The headwaters of rio Uberaba are a marshland mainly dominated by Cyperaceae, with some Poaceae, Nymphaeaceae, Melastomataceae, Asteraceae, and Pteridophyta.When the bottom is not disturbed, the water is clear (Fig. 5).Hyphessobrycon uaiso was found living in schools, occasionally solitary, at average depth of one meter.Schools were mainly found in open areas, devoid of vegetation (Cyperaceae, mainly).Stomach contents of three c&s specimens contained mostly aquatic insect (apparently Diptera larvae), followed by algae, vegetal matter, Acari, and Thecamoebina.More details about the site of collection of H. uaiso are given by Langeani et al. (2007: 120).
Conservation remarks.Recently, Villa-Verde et al. (2012) described Listrura costai and classified this species as vulnerable according to the IUCN categories and criteria for evaluation of threatened species (IUCN, 2001(IUCN, , 2011)).Nowadays, it seems important, whenever possible, to evaluate the conservation status of newly described species right at their descriptions.For Hyphessobrycon uaiso, as L. costai, the extremely restricted distribution (until now the headwater of rio Uberaba), together with a specificity of habitat, relative proximity of human settlements, the use of surrounding land for agriculture, and human water consumption, defining potential threats to the species, allow to apply the criterion D2 (area of occupation less than 20 km²) for the category Vulnerable (VU).Nevertheless, deficiency about population studies or geographical range reductions are not available for the species.Accordingly, it is preferable to consider H. uaiso as data deficient (DD) until more information about its biology and occurrence on the basin is available.
The establishment of conservation measures for the rio Uberaba headwaters is important to conserve its surprisingly diverse restricted ichthyofauna, which include, besides Hyphessobrycon uaiso, another three putative endemic, and so far undescribed taxa: a new Characidae related to Hasemania crenuchoides (of Langeani et al., 2007), a new Crenuchidae, and a possibly undescribed species of Rivulus (Rivulidae).
Table 1.Morphometric data for holotype and paratypes of Hyphessobrycon uaiso from the rio Grande drainage, upper rio Paraná basin.SD = standard deviation; N = number of specimens (including the holotype).

Discussion
Hyphessobrycon is clearly a non-monophyletic genus (Mirande 2009(Mirande , 2010;;Malabarba et al., 2012).The detection of monophyletic groups housed in Hyphessobrycon is expected, however, indicatives of smaller monophyletic units will requires a well-supported analysis of relationships among most of the valid species of Hyphessobrycon, avoiding the numerous generic taxa proposed without autapomorphic characters.This is the justification for the description of this taxon in the Hyphessobrycon sensu Eigenmann (1917).Furthermore, we are in need to describe the components of the Neotropical ichthyofauna rapidly, given the advance of deleterious anthropogenic interference in the aquatic environments.Some characteristics of Astyanax scabripinnis species complex (e.g., head heavy, reduced number of branched anal-fin rays, presence of one humeral spot, and a dark, midlateral, body stripe extending to the tip of the middle caudal-fin rays), like delimited by Bertaco & Lucena (2006), also are present in Hyphessobrycon uaiso, but the body depth (mean 36.8%SL) and mainly the lateral line incomplete in all specimens differ the new species from Astyanax scabripinnis species complex (vs.body depth mean 30-33% of SL and lateral line complete).On the other hand, besides presenting some characters as in Hasemania Ellis (e.g., lateral line incomplete, caudal fin naked), Hyphessobrycon uaiso differs from all Hasemania species by presenting adipose fin (vs.absent in Hasemania, except in some specimens of Hasemania nana, and just one specimen of Hyphessobrycon uaiso) a conspicuous humeral spot (vs.absent in H. hanseni Fowler, H. melanura Ellis, and H. nana Lütken); dorsal fin with ii,8 rays (vs.dorsal fin with ii,9 rays in H. maxillaris); humeral spot vertically rounded in superior portion on adults and anal fin with bony hooks on mature males (vs.humeral spot vertically elongated and absence of bony hooks on mature males of H. crenuchoides Zarske & Gery); and by presence of scale sheath along anal-fin (vs.absent in H. kalunga Bertaco & Carvalho and Hasemania piatan Zanata & Serra).
The condition of dorsal fin with ii,7-8 rays is uncommon among the species of the genus Hyphessobrycon.It is present only in H. arianae, H. guarani, H. otrynus, H. procerus, H. stramineus, and H. wajat.In fact, some of these species (i.e., H. guarani, H. procerus, and H. wajat) are clearly not Hyphessobrycon, because they also present four teeth in the inner row of the premaxilla.These characters define a group inside the family Characidae first proposed by Malabarba & Weitzman (2003) as the Clade A, and posteriorly corroborated and named by Mirande (2009Mirande ( , 2010) ) as Stevardiinae.Indeed, Hyphessobrycon procerus seems to be close related to Lepidocharax Ferreira, Menezes & Quaguio-Grassiotto; also, H. guarani and H. wajat are probably Stevardiinae members.Furthermore, we agree with Malabarba (1998:205) in considering Hyphessobrycon arianae as junior synonym of 'Cheirodon' stenodon, because all characters examined in the H. arianae types (e.g., pseudotympanum, arrangement of teeth in the premaxilla, tricuspid teeth, and color pattern) are also present in 'Cheirodon' stenodon.Hyphessobrycon stramineus, on the other hand, is known by an unique specimen, relatively well preserved (but with superior jaw missing), and according to the analysis of the holotype (MCZ 20772 -by FRC), we concluded that H. stramineus may be close related to Hemigrammus ora Zarske, Le Bail & Géry, based on the dentition (five, tri to pentacuspid, teeth in dentary), color pattern (pale humeral spot, and conspicuous caudal peduncle spot -original description in Ellis in Eigenmann, 1918: 190 and direct observation of holotype), and dorsal fin ii,8 (see redescription of Hemigrammus ora in Jerep et al., 2011).Hyphessobrycon othrynus is a tipical Hyphessobrycon sensu Eigenmann (1917).Hyphessobrycon arianae and H. procerus, differ from H. uaiso by having tricuspid maxillary teeth (vs.maxillary teeth pentacuspid or with more cuspids).
Hyphessobrycon uaiso is described from the upper rio Paraná basin, one of the most sampled basins in the Neotropical region.Langeani et al. (2007) registered 316 species from the upper rio Paraná basin, and about 50 additional species were listed as new taxa awaiting for description.After five years approximately, 26% of those 50 new species were described and 30 other species not listed in that paper (including new species or new records) were recorded to the basin.Thus, the current number of species from the upper rio Paraná basin is around 360, including Hyphessobrycon uaiso.This fact reinforces that the upper rio Paraná basin is a substantial restricted geographic component for the ichthyofauna and it shows that each portion of the basin, i.e., a stream or a small river, can have a particular and specific ichthyofauna.This is evidenced by the new species described in the last five years, including H. uaiso, most of them with restricted distribution (i.e. one stream/river or in some cases a single collection site).Initiatives to preserve and maintain these areas are important for the Neotropical ichthyic diversity conservation.44379, holotype, 30.5 mm SL, Brazil, Rio Grande do Sul. Hemigrammus compressus: BMNH 1905.12.6.4-5, 2 paratypes, male, 31.5-32.5 mm SL, Mexico, Oaxaca, Obispo;CAS 70114 (ex IU 10798, IU 11126)