Peer Review #1 of "A new species of Scapholeberis Schoedler, 1858 (Anomopoda: Daphniidae: Scapholeberinae) from the Colombian Amazon basin highlighted by DNA barcodes and morphology (v0.1)"

Background The Amazon basin is recognized as one of the most complex and species-rich freshwater environments globally. The diversity of zooplankton here remains unknown, with many species undescribed. Methods Here, we describe a new species of Scapholeberis Schoedler, 1858 (Cladocera: Anomopoda: Daphniidae: Scapholeberinae) from the Colombian Amazon Basin, collected with recently designed light traps. The description is based on detailed morphology (based on SEM and light microscopy) of parthenogenetic females, ephippial females, males, and molecular data based on the COI gene. Results Scapholeberis yahuarcaquensis n. sp. has a combination of characters present in Scapholeberis kingi Sars, 1888 and Scapholeberis armata freyi Dumont & Pensaert, 1983. These are a trilobate rostrum, with the middle lobe well developed with sides straight to relatively rounded, the presence of an elongated slit frontal head pore, a dorsal pore in the juncture of the cephalic shield and the valves, and a single denticulate membrane at the posterior rim of the valves, with stronger setae in the last third. The unique characters of the parthenogenetic females are ventral sucker with delicate triangles. Each has a filament-like projection in the lamellae’s inner side and an external section forming convex folds with denticle-like projections in the middle zone of the sucker-plate. There is a peculiar pitted sculpture in the ephippial females and a strong projection in the front of it. The male hook on the limb I with a blunt tip, a quirky lamella-like outgrow in the proximal side, and a paddle with well-developed spines scattered on its surface. The ventral sucker-lamellae in the male is much more developed than the female. The COI gene sequences showed an interspecific mean genetic divergence of 16.4% between S. yahuarcaquensis n. sp. and the closest species S. freyi from Mexico, supporting our results. A coalescence analysis and Barcode Index Number also support the new species based on the DNA sequences. New methods of collecting and integrative biology will give important support to recognize the fauna from the Amazon Basin, one of the most important sources of fresh water in the world that remains unknown in many respects.

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New species of Cyphocharax (Characiformes: Curimatidae) from the upper rio Negro, Amazon basin

Neotropical Ichthyology ◽

10.1590/1982-0224-20130153 ◽

2014 ◽

Vol 12 (2) ◽

pp. 327-332 ◽

Cited By ~ 7

Author(s):

Bruno F. Melo ◽

Richard P. Vari

Keyword(s):

New Species ◽

Amazon Basin ◽

Caudal Peduncle ◽

Caudal Fin ◽

Rio Negro ◽

Fin Rays ◽

Dark Pigmentation ◽

Northern Brazil ◽

Adipose Fin ◽

A New Species

A new species of Cyphocharax, Curimatidae, apparently endemic to the blackwater upper rio Negro of the Amazon basin in northern Brazil, is described.The new species is readily distinguished from its congeners by the presence of a distinctly longitudinally elongate, posteriorly vertically expanding patch of dark pigmentation along the midlateral surface of the caudal peduncle, with the patch extending from the base of the middle caudal-fin rays anteriorly past the vertical through the posterior terminus of the adipose fin. The new species additionally differs from all congeners in details of body and fin pigmentation and meristic and morphometric ratios. Evidence for the assignment of the species to Cyphocharax and the occurrence of other species of the Curimatidae apparently endemic to the upper rio Negro catchment is discussed.

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A new species of Anchoviella Fowler, 1911 (Clupeiformes: Engraulidae) from the Amazon basin, Brazil

Neotropical Ichthyology ◽

10.1590/s1679-62252012000100002 ◽

2012 ◽

Vol 10 (1) ◽

pp. 13-18 ◽

Cited By ~ 5

Author(s):

Marina V. Loeb

Keyword(s):

New Species ◽

Standard Length ◽

Posterior Margin ◽

Amazon Basin ◽

Head Length ◽

Estuarine Species ◽

Dorsal Fin ◽

Fin Ray ◽

Upper Jaw ◽

A New Species

Anchoviella juruasanga is described from the drainages of rios Negro, Madeira, Tapajós, Trombetas, Tocantins, and Jari, in the Amazon basin, Brazil. The new species is distinguished from its congeners by having a short upper jaw, with its posterior tip extending between the verticals through anterior and posterior margins of the pupil (vs. posterior tip of upper jaw extending beyond the vertical through posterior margin of the pupil). Anchoviella juruasanga is also distinct from other strictly freshwater Amazonian species of the genus by the distance from tip of snout to posterior end of upper jaw between 8 and 11% in standard length (vs. 14% or more in A. alleni, A. carrikeri, A. guianensis, and A. jamesi). The anal-fin origin slightly posterior to or at the vertical through the base of the last dorsal-fin ray further distinguishes the new species from A. alleni (anal-fin origin posterior to the vertical through the last anal-fin ray by at least 14% of head length) and A. jamesi (anal-fin origin anterior to the vertical through the last anal-fin ray). An identification key for the Amazonian species of Anchoviella, including marine and estuarine species known to occur in the lower portion of the basin, is presented.

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A taxonomic review of the species of CharaxScopoli, 1777 (Teleostei: Characidae: Characinae) with description of a new species from the rio Negro bearing superficial neuromasts on body scales, Amazon basin, Brazil

Neotropical Ichthyology ◽

10.1590/1982-0224-20130175 ◽

2014 ◽

Vol 12 (2) ◽

pp. 193-228 ◽

Cited By ~ 6

Author(s):

Naércio A. Menezes ◽

Carlos Alberto S. de Lucena

Keyword(s):

New Species ◽

Geographic Distribution ◽

Amazon Basin ◽

Junior Synonym ◽

Museum Collections ◽

Taxonomic Review ◽

Rio Negro ◽

Three New Species ◽

A New Species ◽

Pelvic Fin

The species of Charaxwere reviewed by Lucena (1987) who a little later (1989) added three new species to the genus. Examination of recently collected specimens from museum collections documented the more extensive geographic distribution for most species and revealed the existence of a new species in which superficial neuromasts were discovered and are herein described. These skin structures were also detected in C. metae Eigenmann, 1922. Anal- and pelvic-fin hooks previously observed only on the anal-fin of one species of the genus are described herein in some other species. Charax unimaculatus Lucena is considered a junior synonym of C. michaeli Lucena. All the species are redescribed and the new species described.

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