scholarly journals Two new species of Characidium Reinhardt (Characiformes: Crenuchidae) from northeastern Brazilian coastal drainages

2015 ◽  
Vol 13 (3) ◽  
pp. 487-498 ◽  
Author(s):  
Angela M. Zanata ◽  
Priscila Camelier

Two new species of Characidium , onefrom the rio Pardo basin, and anotherfrom the rio Paraguaçu basin, Bahia, Brazil, are described. The first new speciesis distinguished from its congeners by having conspicuous black vertical traces on body, formed by the concentration of melanophores along posterior margin of scales. The species further differs from most congeners by the presence of a conspicuous 3-shaped black blotch on the caudal fin and isthmus not covered by scales. The other new species is distinguished from congeners by having irregular dark blotches on dorsum alternating elongation to one or the other side of body, usually not connected to lateral blotches. The species can be further characterized by the absence of conspicuous blotches or bars on fins and the presence of secondary sexual dimorphism, such as pelvic fins of mature males longer than in females and with bony hooks.

ZooKeys ◽  
2018 ◽  
Vol 803 ◽  
pp. 71-92 ◽  
Author(s):  
Cheryl B. Barr

Amazonopsisgen. n.is described to includeA.theranyisp. n.from Peru, Venezuela and French Guiana, andA.camachoisp. n.from Venezuela. The descriptions are accompanied by figures illustrating the male and female habitus ofA.theranyi, the male habitus ofA.camachoi, and male genitalia of both species.Amazonopsistheranyiexhibits pronounced secondary sexual dimorphism which likewise may be a characteristic of the genus.Amazonopsismales have modified protarsal and mesotarsal claws, a pair of small spines on the anterior prosternum, and a pair of ventrally directed processes on the posterior metaventrite. Females ofA.theranyidisplay a pair of unique, oval perforations in the cuticle of the pronotum and have unmodified claws; females ofA.camachoiare unknown. Descriptions are furnished of the stream habitats and microhabitats where the study specimens were collected.


2021 ◽  
Vol 61 ◽  
pp. e20216147
Author(s):  
Fernando Cesar Paiva Dagosta ◽  
Mário César Cardoso De Pinna

Two new species of particular biogeographic significance are described from the upper rio Paraguay basin, one of the genus Paracanthopoma (Trichomycteridae, Vandelliinae) and the other of the genus Ernstichthys (Aspredinidae, Hoplomyzontinae). The two species occur sympatrically in the Rio Taquarizinho, tributary of the Rio Taquari, in the upper Paraguay system. Paracanthopoma saci is distinguished from its only congener, P. parva, by a spatulate caudal peduncle; a minuscule premaxillary dentition (reduced to three delicate teeth); the supraorbital latero-sensory canals opening as two separate s6 pores; the caudal fin slightly convex or truncate with round edges; the skull roof entirely open, unossified; the origins of dorsal and anal fins approximately at same vertical; and the pelvic fin with three rays. Ernstichthys taquari is diagnosed among congeners by the narrow bony shields on dorsal and ventral series, not overlapping or contacting each other; by the presence of seven or eight serrations on the posterior margin of the pectoral spine; and by the pectoral-fin spine only slightly larger than subsequent soft rays. Both Paracanthopoma and Ernstichthys were previously unknown outside of the Greater Amazonian river systems (Amazon, Orinoco, Essequibo and smaller surrounding drainages). Their presence restricted to the Rio Taquari is unexpected and suggests a peculiar biogeographical history. Ancestral geographic distributions were reconstructed using S-DIVA and BBM methods in RASP. A majority of resulting hypotheses support that the two species reached the Paraguay from the Amazon. The alternative explanation accounts for their presence in the Paraguay by vicariant events. In no case, their presence in the Paraguay is an ancestral distribution with subsequent Amazonian dispersal. Though unusual, this pattern is also seen in a few other fish taxa, showing that the Rio Taquari is biogeographically hybrid, combining elements from both the Paraguay and Amazon drainages.


2006 ◽  
Vol 4 (3) ◽  
pp. 301-308 ◽  
Author(s):  
Tiago Pinto Carvalho ◽  
Vinicius Araújo Bertaco

Two new species of Hyphessobrycon are described from the upper rio Tapajós basin, Mato Grosso, Brazil. Hyphessobrycon melanostichos is distinguished from its congeners by the combination of a conspicuous longitudinal broad black band beginning on the posterior margin of orbit and reaching the tip of middle caudal fin rays, a distinct vertically elongate humeral spot, and 16 to 18 branched anal-fin rays. Hyphessobrycon notidanos is distinguished from its congeners by the combination of an elongate dorsal fin in mature males, a vertically elongate humeral spot, 2-4 maxillary teeth, iii,8 dorsal-fin rays, and 16 to 21 branched anal-fin rays.


Zootaxa ◽  
2008 ◽  
Vol 1822 (1) ◽  
pp. 1 ◽  
Author(s):  
JONATHAN W. ARMBRUSTER

Peckoltia contains 12 described species, eight of which are considered valid. Peckoltia arenaria, P. filicaudata, and P. ucayalensis are recognized as synonyms of P. bachi and P. kuhlmanni is recognized as a synonym of P. vittata. In addition, two new species are described. The type species of Peckoltichthys and Sophiancistrus are synonyms of P. bachi and both genera are recognized as junior synonyms of Peckoltia. The species of Peckoltia range throughout much of the Amazon basin, the upper Orinoco, the upper Essequibo, and perhaps the Maroni, and can be identified from most other ancistrins by having dentaries that form angle of 90° or less and from others with angled dentaries by lacking the synapomorphies of those genera. The species of Peckoltia vary from one another mostly in coloration. Peckoltia braueri, P. caenosa n. sp., P. cavatica and P. vittata lack spots on the head while the other species have them. Peckoltia braueri and P. cavatica have orange bands in the dorsal and caudal fins and have the bones and plates of the head and nape outlined in black (vs. no orange bands and head plates and bones not outlined in black in P. caenosa and P. vittata). Peckoltia caenosa has a color pattern consisting of dark vermiculations on the head and abdomen (vs. saddles or blotches on the head and faint dark spots on the abdomen in P. vittata). Among the species with spots on the head, P. lineola n. sp. and P. vermiculata have some of the spots combining to form vermiculations (vs. spots free in P. bachi, P. brevis, P. furcata, and P.oligospila) with the vermiculations larger than the pupil in P. lineola and narrower in P. vermiculata and the vermiculations radiating from a central point in P. vermiculata vs. no such pattern in P. lineola. Peckoltia bachi can be identified from the other species by having widened pelvic-fin spines that can be pulled ventrally such that they are completely ventral and parallel to the body (vs. pelvic-fin spines narrow and cannot be adducted ventral to body) and by having the eye low on the head (vs. high). Peckoltia brevis can be identified from P. furcata and P. oligospila by having well-developed dorsal saddles (vs. saddles faint), no spots on the body behind the nape (vs. spots generally present behind the nape); from P. oligospila by having bands in the caudal fin (vs. spots); and from P. furcata by having the lower caudal-fin spine longer than the upper (vs. upper spine longer). Peckoltia furcata can be identified from P. oligospila by having the upper caudal-fin spine longer than the lower (vs. lower spine longer) and by having bands in the caudal fin (vs. spots). Ancistrus yaravi had been recognized as a species of Peckoltia. The type of A. yaravi is lost, but the original description suggests that the species is the senior synonym of Neblinichthys roraima. A revised morphological phylogeny demonstrates the lack of support for Peckoltia and Hemiancistrus as monophyletic, and phenetic definitions are provided for the two genera. The phylogeny also demonstrates a lack of support of the genus Watawata.


ZooKeys ◽  
2020 ◽  
Vol 946 ◽  
pp. 113-151
Author(s):  
Hans R. Feijen ◽  
Cobi Feijen

The literature on Sri Lankan Diopsidae is reviewed. Eight Diopsidae are now known to occur in Sri Lanka, five species in the genus Teleopsis and one species each in the genera Sphyracephala, Diopsis, and Cyrtodiopsis. The presence of Cyrtodiopsis requires confirmation to exclude the possibility of mislabelling. All five Teleopsis species are endemic, as are the Diopsis species and probably the Cyrtodiopsis species. Only Sphyracephala bipunctipennis Senior-White has a larger distribution as it also occurs in India. A key is presented for the Diopsidae of Sri Lanka. Three Teleopsis species were already known to occur in Sri Lanka: T. ferruginea Röder, T. krombeini Feijen and T. maculata Feijen. These species form the T. ferruginea species group. Two new species are now described for this group: Teleopsis neglectasp. nov. and Teleopsis sororasp. nov.Teleopsis ferruginea is redescribed, as an earlier redescription turned out to be based on a series of specimens of its sister species T. sororasp. nov. The other three Diopsidae of Sri Lanka are listed and illustrated. Allometric aspects of the five Teleopsis species are discussed. Three Teleopsis species are sexually dimorphic with regard to eye span, while two species are monomorphic. It is assumed that sexual dimorphism developed independently in the T. ferruginea species group. This brings the number of known cases of independent development of sexual dimorphism in the Diopsidae to ten.


Zootaxa ◽  
2017 ◽  
Vol 4243 (1) ◽  
pp. 187 ◽  
Author(s):  
WILLIAM D., JR. ANDERSON ◽  
G. DAVID JOHNSON

In late July/early August 2015, ichthyologists from the Bishop Museum collecting fishes off Pohnpei in the Caroline Islands group, western Pacific Ocean, obtained specimens of two undescribed species of Grammatonotus. One of the new species, G. xanthostigma, closely resembles the recently described G. brianne, differing most strikingly in the shape of the caudal fin. The other, G. pelipel, is distinctive in having the following combination of characters: disjunct lateral line, barred pattern of coloration (most distinctive in small individuals), and caudal fin truncate to slightly emarginate in small specimens, but with upper and lower lobes produced in largest example known. Herein we provide characters that distinguish callanthiids from other percoids and that distinguish Grammatonotus from Callanthias, the other genus in the family Callanthiidae, along with descriptions of the new species. 


Zootaxa ◽  
2019 ◽  
Vol 4543 (1) ◽  
pp. 90
Author(s):  
CARLOS MOLINERI ◽  
CRISTIAN E. GRANADOS-MARTINEZ

Two new species of Campsurus from Colombia are herein described, based on adults of both sexes and eggs. Campsurus vichada sp. nov. from the albifilum group, is separated from the other species in this group by: abdominal terga shaded slightly darker posteriorly, with a pale median band and pale closed markings, and pedestals short and subquadrate, main lobes of penes very long and slender, among other characters. Its sister relation with C. homaulus and C. gracilipenis is hypothesized through a cladistic analysis. A key is presented for the six species in the albifilum group of Campsurus.Campsurus cristales sp. nov. from the segnis group, closely related to C. janae, is diagnosed by: posterior margin of male abdominal sternum IX tri–lobed, pedestal strongly elongated and penes with a strongly expanded dorsal area, among other features. 


Zootaxa ◽  
2006 ◽  
Vol 1185 (1) ◽  
pp. 21 ◽  
Author(s):  
DOUGLAS ZEPPELINI ◽  
BRUNO CAVALCANTE BELLINI

Two new species of Seira Lubbock 1869 are described and illustrated. The males of these species show modifications in the fore legs, probably associated with sexual courtship and/or mating behavior. Despite the similarity of the modifications of the two species, they are not otherwise similar. Thus the similarity is due to convergence rather than homology. These are the first records of sexual dimorphism other than genital openings in Entomobryidae.


Zootaxa ◽  
2009 ◽  
Vol 2301 (1) ◽  
pp. 55-68 ◽  
Author(s):  
JESSER F. SOUZA-FILHO ◽  
ANDRÉ R. SENNA

The genus Elasmopus has a worldwide distribution with most species living in warm waters. This work describes two new species, both from off the northeast Brazilian coast, including its oceanic banks of Fernando de Noronha Chain. The first new species, E. karamani sp. nov., is easily recognized by palm of gnathopod 2 with a medial concave portion, posterior margin of basis of pereopod 5 and 6 concave, epimeron 3 produced in a sharp spine, and the uropod 3 rami 2.4 times the peduncle length. The other one, E. lejeunei sp. nov., is very similar to E. balkomanus Thomas & Barnard, 1989 and E. lemaitrei Ortiz & Lalana, 1994 in having propodus of gnathopod 2 without palmar corner and posterior margin of basis of pereopod 5 concave. However, it differs from those by presenting gnathopod 2 with a weakly developed process near hinge of dactylus with some robust setae, followed by two tubercles. The propodus inner face presents one ridged line, about 1/3 of propodus length, and perpendicular lines of setae, from the proximal portion of the ridged line almost to the dactylus hinge. A key to all species of the genus Elasmopus recorded in the Brazilian coast is given.


2016 ◽  
Vol 14 (1) ◽  
Author(s):  
Luiz Fernando Caserta Tencatt ◽  
Willian Massaharu Ohara

Abstract Two new species of Corydoras are described from the rio Madeira basin, Brazil. The intermediate long-snouted new species can be distinguished from its congeners by presenting the following combination of features: posterior margin of dorsal-fin spine with laminar serrations directed towards the origin of the spine; presence of two longitudinal black stripes on flanks; anterior portion of dorsal fin with sparse black chromatophores, not forming any conspicuous pattern; absence of a conspicuous black marbled coloration pattern on head; black spots on caudal fin, some spots arranged, forming transversal bars; and brownish dorsal-fin spine. The short-snouted new speciescan be distinguished from its congeners by the following combination of features: short mesethmoid; posterior laminar expansion of infraorbital 2 very reduced, not in contact with compound pterotic; two or three longitudinal black stripes on flanks; absence of an oblique or vertical black blotch across the eye; anterior portion of dorsal fin with sparse black chromatophores, not forming any conspicuous pattern; and ventral surface of trunk naked or covered by sparse platelets.


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