[Ichthyology • 2019] Molecular Phylogeny of the Ghost Knifefishes (Gymnotiformes: Apteronotidae)

in Bernt, Tagliacollo & Albert, 2019.  

DOI:  10.1016/j.ympev.2019.02.019 

 twitter.com/MJBernt 

Highlights: 

• Most species-comprehensive, data-rich phylogeny of the ghost knifefishes to date.

• Multi-locus phylogeny based on three mitochondrial and four nuclear loci.

• Orthosternarchus + Sternarchorhamphus placed sister to all remaining genera.

• Substantial polyphyly within Apteronotus.

• New suprageneric classification for Apteronotidae.

 DOI:  10.1016/j.ympev.2019.02.019  
twitter.com/MJBernt 

 Maxwell J. Bernt, Victor A. Tagliacollo and James S. Albert. 2019. Molecular Phylogeny of the Ghost Knifefishes (Gymnotiformes: Apteronotidae). Molecular Phylogenetics and Evolution. In Press. DOI:  10.1016/j.ympev.2019.02.019 

twitter.com/MJBernt/status/1115033555770462210

    

[Ichthyology • 2018] Melanosternarchus amaru • A New Genus and Species of Electric Ghost Knifefish (Gymnotiformes: Apteronotidae) from the Amazon Basin

Melanosternarchus amaru 

Bernt, Crampton, Orfinger & Albert, 2018

 DOI: 10.11646/zootaxa.4378.4.1 

Abstract
We describe Melanosternarchus amaru as a new genus and species of Apteronotidae from the deep channels of blackwater and clearwater tributaries of the Amazon River in Brazil and Peru. The new species superficially resembles members of the widespread “Apteronotus” bonapartii species group, from which it can be readily distinguished by expanded bones of the infraorbital laterosensory canal. It can further be distinguished from all other apteronotids by a unique combination of characters: reduced premaxillary dentition, a large gape, and an absence of scales from the entire dorsum. A molecular phylogenetic analysis using three mitochondrial loci and one nuclear locus (~3000 bp) places this genus as sister to Compsaraia, and these two genera together as a clade sister to Pariosternarchus; all nodes with strong statistical support. The clade formed by these three genera includes five species, four of which are restricted to the Amazon basin. The apparent habitat preference of the new species for low-conductivity blackwater and clearwater rivers has not been reported in other apteronotid species.

Keywords: Pisces, Neotropics, Peru, Brazil, diversity, Blackwater, taxonomy

FIGURE 2. Lateral view of two living specimens of Melanosternarchus amaru, ANSP 200459.

Melanosternarchus, new genus

Type species. Melanosternarchus amaru, new species,

by monotypy and original designation.

Etymology. Melano from the Greek melas, meaning black in reference to dark pigmentation and presence in blackwater rivers, and sternarchus, a name commonly used in apteronotid taxonomy, from the Greek sternon (chest) and archos (rectum), referring to the anterior position of the anus.

Melanosternarchus amaru, new species

Etymology. The species name is from the Quechuan amaru, a mythical serpent, referring to the snakelike shape of this fish. A noun in apposition.

Maxwell J. Bernt, William G. R. Crampton, Alexander B. Orfinger and James S. Albert. 2018. Melanosternarchus amaru, A New Genus and Species of Electric Ghost Knifefish (Gymnotiformes: Apteronotidae) from the Amazon Basin. Zootaxa. 4378(4); 451–479. DOI: 10.11646/zootaxa.4378.4.1

ResearchGate.net/publication/323120879_Melanosternarchus_amaru_a_new_genus_and_species_of_electric_ghost_knifefish_from_the_Amazon_Basin

 twitter.com/MJBernt/status/962898598013923329
facebook.com/AlexOrfinger/posts/10156093177785419

[Ichthyology • 2017] Compsaraia iara • A New Species of Deep-Channel Electric Knifefish Compsaraia (Apteronotidae, Gymnotiformes) from the Amazon River

Compsaraia iara

Bernt & Albert, 2017

  DOI: 10.1643/CI-16-529 

The deep channels of large rivers throughout the humid Neotropics are occupied by diverse and abundant assemblages of electric knifefishes. Historically this habitat has been poorly sampled, but extensive benthic trawling efforts in the Brazilian Amazon in the 1990s produced large numbers of electric fishes especially in the family Apteronotidae. A large number of these specimens, initially identified as Porotergus, have been found to belong within Compsaraia, a genus with two species described from the Orinoco and western Amazon. From this material we describe a new species, from the Amazon River in Brazil, and provide a new diagnosis for the genus. This species is readily distinguished from congeners by a short, rounded snout and small, subterminal mouth with reduced dentition. This species inhabits large rivers in the Eastern and Central Amazon between Ilha Grande de Gurupá and the mouth of the Rio Içá. This description brings the total number of valid apteronotid species to 95.

Fig. 3. Detail of head and pigmentation for Compsaraia samueli (top), MUSM 37172, 241 mm TL, and Compsaraia iara, FMNH 128428, 235 mm TL in lateral view (A), dorsal view (B), and ventral view (C). Scale bar equals 1 cm. 

Compsaraia iara, new species

Etymology.— This species is named for the Iara, a water nymph from Tupi-Brazilian folklore said to reside in the rivers of the Brazilian Amazon and often blamed for the disappearance of fishermen. A noun in apposition. 

Maxwell J. Bernt and James S. Albert. 2017. A New Species of Deep-Channel Electric Knifefish Compsaraia (Apteronotidae, Gymnotiformes) from the Amazon River.
 Copeia. 105(2); 211-219.  DOI: 10.1643/CI-16-529

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