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Neblinichthys pilosus, a new genus and species of mailed catfish from the Rio Bario system, southern Venezuela (Pisces, Siluriformes, Loricariidae).
... However, all species of Neblinicthys possess an adipose fin, while even the smallest specimen of A. loro examined (MZUEL 7900, 23.1 mm SL) completely lacks an adipose fin. Additionally, Neblinichthys was described by Ferraris et al. (1986) for species of ancistrins exhibiting elongate, anteriorly directed bristles on the snout of males. Currently, Neblinichthys comprises six species that inhabit small streams across the Western Guiana Shield (Armbruster & Taphorn, 2013). ...
Araichthys loro, a new genus and species of the suckermouth armored catfish family Loricariidae, is described from the rio Papagaio and tributaries, rio Tapajós basin, Mato Grosso State, central Brazil. Araichthys is distinguished from all other genera of the Ancistrini by features of body and head plates, odontodes of breeding males, and osteology, and by the absence of an adipose fin. A phylogenetic analysis of morphological characters obtained Araichthys as part of a monophyletic group that also includes Pseudolithoxus, Ancistrus and Lasiancistrus based on the presence of a large gap with a strut between the anterior process of the pterotic-supracleithrum and its main body, three rows of plates at thinnest part of caudal peduncle, fleshy tentacles on snout with a sheath partially detached from odontodes, and small tentacles on pectoral fins partially detached from odontodes.
We provide a general compilation of the diversity and geographical distribution of Amazonian fishes, updated to the end of 2018. Our database includes documented distributions of 4214 species (both Amazonian and from surrounding basins), compiled from published information plus original data from ichthyological collections. Our results show that the Amazon basin comprises the most diverse regional assemblage of freshwater fishes in the world, with 2716 valid species (1696 of which are endemic) representing 529 genera, 60 families, and 18 orders. These data permit a view of the diversity and distribution of Amazonian fishes on a basinwide scale, which in turn allows the identification of congruent biogeographical patterns, here defined as the overlapping distributions of two or more lineages (species or monophyletic groups). We recognize 20 distinct distributional patterns of Amazonian fishes, which are herein individually delimited, named, and diagnosed. Not all these patterns are associated with identifiable geographical barriers, and some may result from ecological constraints. All the major Amazonian subdrainages fit into more than one biogeographical pattern. This fact reveals the complex history of hydrographical basins and shows that modern basin-defined units contribute relatively little as explanatory factors for the present distributions of Amazonian fishes. An understanding of geomorphological processes and associated paleographic landscape changes provides a far better background for interpreting observed patterns. Our results are expected to provide a framework for future studies on the diversification and historical biogeography of the Amazonian aquatic biota.
Neblinichthys peniculatus is described from specimens collected in the río Carapo (río Paragua - río Caroni drainage), which drains the southern flank of Cerro Guaiquinima in southeastern Venezuela. Neblinichthys peniculatus differs from all congeners by having mottling on the caudal peduncle consisting of dark spots and dashes (vs. caudal peduncle all about the same color or light below and dark above) and by having spots on the head (spots less conspicuous in nuptial males as the head is darker; vs. no spots). Uniquely among Neblinichthys for which nuptial males are known, the hypertrophied odontodes on the snout are rather short, none as large as the eye diameter.
Although freshwaters contribute only about .01% to Earth’s water supply, their fishes now number more than 10,000 species and thus account for at least 40% of all fish species. The continental fish faunas differ greatly in taxonomic composition and species richness, our state of knowledge of them, and the rate of discovery of unknown kinds. The ichthyofaunas of North America (about 1,050 species), Europe (about 360), and Australia-New Guinea (about 500), are the most thoroughly documented, but new species continue to be described based on discovery of previously unseen forms and species-level taxonomic splits of known species. The ichthyofaunas of tropical Asia (perhaps >3,000), Africa (perhaps >3,000 species), and South and Central America (perhaps >>5,000 species), are species rich yet incompletely known. Tropical freshwaters are the hot spots of recent and likely future ichthyological discoveries. Especially in the tropics, discoveries of species that signal new generic-level taxa are common, and new family-level groups are found occasionally. Everywhere on-going phylogenetic studies often suggest or reveal unsuspected relationships. These are times of exciting discovery and advancement of knowledge in freshwater ichthyology. New discoveries beckon us to seek the many remaining unknowns in the diversity of life on our planet. These are also times of rapid and destructive change in freshwater habitats around the globe. These threats alert us to the increasing potential for permanent loss and ignorance of much our planet’s rich aquatic biota.
A phylogenetic analysis of nearly all genera of the Hypostominae and the Ancistrinae is provided based on osteology, external anatomy, and digestive tract anatomy. The results suggest that the Hypostominae is a paraphyletic assemblage. Delturus and Upsilodus form a monophyletic group sister to all other loricariids. Hemipsilichthys, Isbrueckerichthys, Kronichthys, and Pareiorhina form a monophyletic group with Neoplecostomus and the Hypoptopomatinae and are transferred to the Neoplecostominae. The remainder of the Hypostominae is made paraphyletic by the continuing recognition of the Ancistrinae. Ancistrinae is returned to the Hypostominae and recognized as a tribe, Ancistrini. In addition, four new tribes (Corymbophanini, Hypostomini, Pterygoplichthini, and Rhinelepini) are described. Hypostomus is also paraphyletic, the bulk of it forming a monophyletic clade with Aphanotorulus, Cochliodon, and Isorineloricaria. All of the potential monophyletic groups within Hypostomus grade into one another; therefore, Aphanotorulus, Cochliodon, and Isorineloricaria are placed in the synonymy of Hypostomus. Pterygoplichthys and Glyptoperichthys are also polyphyletic, and Liposarcus and Glyptoperichthys are recognized as synonyms of Pterygoplichthys. Sister to Pterygoplichthys is the Hemiancistrus annectens group (including Hypostomus panamensis) which represents an undescribed genus. The phylogeny presented is compared with previous hypotheses. © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society, 2004, 141, 1−80.
Neblinichthys brevibracchium and N. echinasus are new sympatric species from upland tributaries of the Mazaruni River (Essequibo River basin) of Guyana. These two new species are the first Neblinichthys reported from Guyana. Adult males of both new species have short pectoral-fin spines and several series of hypertrophied odontodes covering the entire dorsal surface and along the entire edge of the snout. They are distinguished from each other by dorsal-fin base length/standard length (18.1-22.8%
in N. brevibracchium vs. 24.3-27.0% in N. echinasus), dorsal-anal distance/SL 13.7-18.3% in N. brevibracchium vs. 11.9-12.5% in N. echinasus), by having the snout decreasing in steep arc just anterior to eyes and then flattening in area anterior of nares in N. brevibracchium vs. the snout tapering shallowly and continuously from eyes to snout tip in N. echinasus); and by having the adpressed dorsal fin reaching the anterior preadipose plate in N. brevibracchium (vs. not reaching anterior preadipose plate in N.
echinasus). They are distinguished from all congeners by lacking odontodes on the opercle (vs. odontodes present); and by completely lacking an iris operculum (vs. congeners with small iris operculum present or at least dorsal portion of iris flat instead
of rounded). Neblinichthys echinasus and N. brevibracchium differ from all congeners by having a spotted or vermiculated pigment pattern on the abdomen (vs. abdomen plain); in N. echinasus the abdomen is darkly pigmented with bold white spots and in Neblinichthys brevibracchium the abdomen is light-colored with gray spots and vermiculations. Neblinichthys brevibracchium and N. echinasus differ from N. roraima by having one to two preadipose plates (vs. four or more). New observations revealed
Neblinichthys roraima and N. yaravi to be distinct, with N. roraima having four or more preadipose plates and N. yaravi having
one or two. Both are present in the upper río Caroní, an Orinoco tributary that drains the slopes of Mount Roraima and other
mountains of the Pacaraima Range in Venezuela and interdigitates with headwaters of the Mazaruni River.
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