Lepthoplosternum

Taxobox
name = "Lepthoplosternum"
regnum = Animalia
phylum = Chordata
classis = Actinopterygii
ordo = Siluriformes
familia = Callichthyidae
subfamilia = Callichthyinae
genus = "Lepthoplosternum"
genus_authority = Reis, 1997
type_species = "Callichthys pectoralis"
type_species_authority = Boulenger, 1895
subdivision_ranks = Binomial name
subdivision =
"Lepthoplosternum altamazonicum"
Reis, 1997
"Lepthoplosternum beni"
Reis, 1997
"Lepthoplosternum pectorale"
(Boulenger, 1895)
"Lepthoplosternum stellatum"
Reis & Kaefer, 2005
"Lepthoplosternum tordilho"
Reis, 1997
"Lepthoplosternum ucamara"
Reis & Kaefer, 2005

"Lepthoplosternum" is a small genus of freshwater catfish in the Callichthyinae subfamily of the armored catfish family, and consists of six species.cite journal|url=http://silurus.acnatsci.org/ACSI/library/biblios/2007_Ferraris_Catfish_Checklist.pdf|title=Checklist of catfishes, recent and fossil (Osteichthyes: Siluriformes), and catalogue of siluriform primary types|first=Carl J., Jr.|last=Ferraris|journal=Zootaxa|volume=1418|pages=1–628|year=2007|format=PDF]

Taxonomy

The type species for this genus is "Callichthys pectoralis". The name is derived from the Greek "leptos", meaning "thin", the Greek "hoplon", meaning "weapon", and the Greek "sternon", meaning "chest" or "sternum". [FishBase genus | genus = Lepthoplosternum | year = 2006 | month = March] "Lepthoplosternum" is relatively basal among callichthyines, being sister to the clade comprising "Megalechis" + "Dianema" + "Hoplosternum". "Callichthys" is the most basal genus in the subfamily.cite journal|title=Two New Species of the Neotropical Catfish Genus "Lepthoplosternum" (Ostariophysi: Siluriformes: Callichthyidae)|first=Roberto E.|last=Reis|authorlink=Roberto Esser dos Reis|coauthors=Kaefer, Cíntia C.|journal=Copeia|year=2005|issue=4|pages=724–731|doi=10.1643/0045-8511(2005)005 [0724:TNSOTN] 2.0.CO;2|volume=2005|doilabel=10.1643/0045-8511(2005)005[0724:TNSOTN]2.0.CO;2]

"L. stellatum" and "L. ucamara" are hypothesized to form a partially unresolved polytomy with "L. pectorale" and "L. beni", which are sister-species to each other. "L. tordilho" is sister to these four species and "L. altamazonicum" is the most basal species.

Distribution and habitat

"Lepthoplosternum" is widely distributed in cis-Andean South America south of the Orinoco River basin. "L. pectorale" is from the Paraguay River, "L. altamazonicum" is known only from the upper Amazon River basin in Peru and Brazil, "L. beni" is from the upper Madeira River basin in Bolivia and Peru, and "L. tordilho" is from the lower Jacui River drainage in southern Brazil. "L. stellatum" is so far known from the type locality only, the Igarapé Repartimento, a tributary of the mouthbay lake, Tefé Lake, some 6 km south of the town of Tefé, Amazonas, Brazil. "L. ucamara" is known from the Pacaya-Samiria National Reserve in the lower Ucayali River in Peru and from the area ofconfluence of the Solimões River and Japurá River in Brazil.

"Lepthoplosternum" species usually inhabit lentic or slow flowing water bodies and are often associated with marginal or floating vegetation. "L. ucamara" has even been found in hypoxic conditions. However, the type locality of "L. stellatum" is a stream, permanently flowing and well oxygenated.

Description

"Lepthoplosternum" species are the smallest callichthyines (maximum standard length 60.3 mm) and are easily recognized by two synapomorphies: the lower lip with deep medial notch and a small, additional lateral notch forming fleshy projections on each side; and a single unbranched ray preceding the branched ones on the anal fin.

References