scholarly journals New Myloplus from Essequibo River basin, Guyana, with discussion on the taxonomic status of Myleus pacu (Characiformes: Serrasalmidae)

2019 ◽  
Vol 17 (4) ◽  
Author(s):  
Marcelo C. Andrade ◽  
Hernán López-Fernández ◽  
Elford A. Liverpool

ABSTRACT A new species in the serrasalmid genus Myloplus is described from the middle Mazaruni River, Essequibo River basin, Guyana. The new species is similar to Myleus pacu and Myloplus planquettei in its silver to purplish black coloration and its overall morphology, and has a putative syntopic distribution with those species. The new species is, however, readily distinguishable from the other two by meristic counts of the unpaired fins and by differences in color pattern, primarily in males. Additionally, we provide comments on Myleus pacu and other species that have been confounded under that name.

Zootaxa ◽  
2006 ◽  
Vol 1116 (1) ◽  
pp. 29 ◽  
Author(s):  
FRANCISCO PROVENZANO ◽  
NADIA MILANI

A new species of suckermouth armored catfish, Cordylancistrus nephelion, is described from seven specimens collected in tributaries of the Tuy River in the Caribbean Sea basin of north-central Venezuela. Cordylancistrus nephelion can be distinguished from the other species assigned to its genus by its unique color pattern, the head and body being marked with irregular white spots. Cordylancistrus nephelion is the third species of the genus described from Venezuela: Cordylancistrus torbesensis (Schultz 1944) from the Mérida mountain range (Cordillera de Mérida), Orinoco River basin; C. perijae Pérez and Provenzano 1996 from Perijá mountain range (Sierra de Perijá), Maracaibo Lake basin; and now C. nephelion from the La Costa mountain range (Cordillera de La Costa). These three species inhabit isolated foothill rivers and have very restricted geographic distributions. The extreme alteration of the Tuy River basin by humans may threaten Cordylancistrus nephelion and the other fish species endemic to the basin with extinction. An artificial key for the species assigned to the genus Cordylancistrus is presented.


Zootaxa ◽  
2018 ◽  
Vol 4527 (4) ◽  
pp. 588
Author(s):  
ALBERTO ARANO-RUIZ ◽  
LAZARO W. VIÑOLA-LÓPEZ ◽  
REINALDO ROJAS-CONSUEGRA ◽  
CARLOS RAFAEL BORGES-SELLEN

A new species of raninid crustacean, Vegaranina rivasi sp. nov, is described based on three specimens collected from a Late Cretaceous deposit in central Cuba. Previous studies assigned one of the specimens to Vegaranina precocia (Feldmann, Vega, Tucker, Garcia-Barrera & Avendano, 1996), a species described from the Late Cretaceous of Mexico. However, after collecting the new specimens and recent major revisions of the group, we identified a unique combination of characters in the Cuban specimens that separate them from the other species in the genus. 


Zootaxa ◽  
2011 ◽  
Vol 2754 (1) ◽  
pp. 27 ◽  
Author(s):  
MARC RIUS ◽  
PETER R. TESKE

Pyura stolonifera is a large solitary ascidian found in Africa, Australasia and South America. The taxonomic status of different populations of this species is disputed, especially since there is evidence for several distinct morphological and genetic units that point towards the existence of multiple cryptic species. While some researchers still recognize P. stolonifera as a single species, others treat the different populations as distinct species. Here, we present a revision of the P. stolonifera species complex based on the examination of samples from all regions where there are reliable reports of this taxon. We recognize four species that are both morphologically and genetically distinct, one of which is new to science and is formally described here. This species is morphologically distinct from the other three members of the species complex in terms of the colour and texture of the tunic, the arrangement of the gonads within the gut and the shape of the dorsal tubercle, among other characters. We name the new species Pyura dalbyi after Dr. J.E. Dalby Jr., whose research on its ecology and distribution provided the incentive for examining this species more closely.


Zootaxa ◽  
2020 ◽  
Vol 4808 (3) ◽  
pp. 491-506
Author(s):  
MIGUEL ÁNGEL CORTÉS-HERNÁNDEZ ◽  
CARLOS DONASCIMIENTO ◽  
HERNANDO RAMÍREZ-GIL

A new species of Pimelodella is described from western Andean tributaries of the Orinoco River basin. The new species differs from all congeners by a unique set of characters that includes long maxillary barbel, surpassing the dorsal lobe of the caudal fin; relatively short adipose fin (32.8–36.4 of SL); 40–42 total vertebrae; posterior margin of pectoral-fin spine with 12–18 retrorse dentations along basal two thirds; laterosensory canal foramina of dentary and preopercle large and externally conspicuous; a brown faint and narrow midlateral stripe extending from the pseudotympanum, fading posteriorly along the caudal peduncle, and ending as a spot at the caudal-fin base; and dorsal-fin base darkly pigmented, from spinelet to posteriormost interradial membrane. Taxonomic status of P. pallida and presence of P. cruxenti in Colombia are also discussed. 


Zootaxa ◽  
2007 ◽  
Vol 1529 (1) ◽  
pp. 1-15 ◽  
Author(s):  
ŞAKIR ÖNDER ÖZKURT ◽  
MUSTAFA SÖZEN ◽  
NURI YIĞIT ◽  
IRFAN KANDEMIR ◽  
REYHAN ÇOLAK ◽  
...  

We report a new species of Spermophilus ( Rodentia: Sciuridae), here designated as S. torosensis sp. nov., distributed in the Taurus Mountains in southern Anatolia, Turkey. A total of 161 specimens of the genus Spermophilus from Turkey and Iran were analyzed for their morphological, morphometric, and karyological characteristics. Uni- and multi-variate statistical analyses of morphologic data for 95 adult specimens yielded 4 distinct groups. Taxonomic evaluations classified the specimens into 4 species Spermophilus citellus, S. xanthopymnus, S. fulvus and S. torosensis sp. nov. Morphometrics, coat coloration, a brush-shaped tail, and a NFa value of 72 are diagnostic characters that distinguish S. torosensis sp. nov. from the other species. In Turkey, S. torosensis sp. nov. was found in 6 locations. The karyotype of S. fulvus also is described for the first time as 2n= 36, NFa= 70 and NFa= 66; new karyotypic data is reported for S. xanthoprymnus from Iran and Turkey.


Zootaxa ◽  
2018 ◽  
Vol 4377 (2) ◽  
pp. 296
Author(s):  
ANDRES FABIAN HERRERA-FLOREZ ◽  
OSCAR EFRAIN ORTEGA MOLINA

A new species of Umanella Gauld 1991, U. tricoloripes Herrera-Florez, sp. n., is described from two males collected in Colombia. Umanella tricoloripes sp. nov. differs substantially from the other species of the genus in color pattern. 


Zootaxa ◽  
2009 ◽  
Vol 2146 (1) ◽  
pp. 53-60 ◽  
Author(s):  
F. F. SALLES ◽  
C. N. FRANCISCHETTI ◽  
E. D. G. SOARES

In the present work a new species of Homoeoneuria is described based on nymphs and adults from Southeastern Brazil. Based on cladistics, the new species belongs to the subgenus Homoeoneuria.s.s. Homoeoneuria (H). watu sp. n., besides being the second species of the genus reported from South America, is the first representative of the subgenus from the region. The new species can be distinguished from the other described species of the genus by the following combination of characters: In the adult stage, (1) pronotum with prominent posteromedian pale yellow spot almost reaching anterior margin; (2) abdominal color pattern; (3) shape of penes. In the nymph, (1) head heavily washed with brownish-orange between compound eyes and ocelli; (2) antennal pedicels with short, thick setae; (3) small paired tubercles present on vertex and anterior margin of pronotum; (4) galea-lacinia of maxillae with submarginal row of 20–21 long, spinous setae; (5) abdominal color pattern. Comments on the biology of the new species are also provided.


Zootaxa ◽  
2010 ◽  
Vol 2534 (1) ◽  
pp. 48 ◽  
Author(s):  
RENILDO RIBEIRO DE OLIVEIRA ◽  
JANSEN ZUANON ◽  
LUCIA RAPP PY-DANIEL ◽  
MARCELO SALLES ROCHA

The loricariid genus Peckoltia currently encompasses 13 valid species ranging throughout the Amazon basin in Brazil, Venezuela, Colombia, Peru, and Guyanas. Peckoltia is included in the tribe Ancistrini, but its relationships with other taxa within the tribe are not well established. In this paper we describe a new species of Peckoltia from the rio Tapajos drainage, Para State, Brazil. Peckoltia compta, new species, is characterized by a bold color pattern consisting of large dark transversal bars on body and thick longitudinal dark stripes on snout and head. The new species is most similar in color pattern to P. vittata but can be distinguished from all its congeners by the presence of a pale line inside each dark stripe running from the snout tip to anterior margin of eyes (vs. absence of such clear lines and a mottled appearance in P. vittata, and a mix of vermiculations and spots on the head of the remaining congeners). A brief discussion on the taxonomic status of the nominal species Peckoltia vittata is also presented.


Zootaxa ◽  
2021 ◽  
Vol 4903 (2) ◽  
pp. 217-241
Author(s):  
ANTONIO MORAES-DA-SILVA ◽  
RENATA CECÍLIA AMARO ◽  
PEDRO M. SALES NUNES ◽  
MIGUEL TREFAUT RODRIGUES ◽  
FELIPE FRANCO CURCIO

We describe a new species of watersnake of the genus Helicops from the Tocantins-Araguaia River Basin based on characters of coloration and hemipenial morphology, also corroborated by a molecular phylogenetic analysis including 18 terminals of 10 additional congeners. The new species superficially resembles the spotted-patterned He. leopardinus, but differs from it in exhibiting dorsal spots fused into irregular bands, and a unique hemipenial structure with two pairs of distinctly enlarged basal spines. In addition, despite the superficial resemblance of color pattern, our genetic evidence indicates that the new species does not belong to the He. leopardinus radiation, representing the sister group of a component including terminals of this species, He. modestus, and He. infrataeniatus. Finally, we discuss the apparent restriction of the new species to the Tocantins-Araguaia Basin with focus on vicariant processes that may have promoted its differentiation, as well as on the conservation challenges in an area severely affected by anthropic impacts associated with the rapid expansion of hydroelectric and agricultural sectors in the Brazilian Cerrado. 


Zootaxa ◽  
2017 ◽  
Vol 4281 (1) ◽  
pp. 120
Author(s):  
RODNEY R. CAVICHIOLI1 ◽  
GABRIEL MEJDALANI

A new species of the Neotropical sharpshooter genus Iragua Melichar, 1926, I. albinoi sp. nov., is described and illustrated from the Colombian department of Huila (holotype deposited in Coleção Entomológica Pe. Jesus S. Moure, Departamento de Zoologia, Setor de Ciências Biológicas, Universidade Federal do Paraná). The new taxon can be readily distinguished from the other 13 known species of the genus by the presence of a pair of unciform processes at the aedeagal atrium, as well as by the color pattern of the forewings. The first detailed description of the female terminalia of a species of Iragua (I. ferruginea Cavichioli, 1991 from the Brazilian state of Rondônia) and an updated key to males of the genus are also provided. 


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