A new genus and two new species of Stevardiinae (Characiformes: Characidae) with a hypothesis on their relationships based on morphological and histological data
Author
Ferreira, Katiane M.
Author
Menezes, Naércio A.
Author
Quagio-Grassioto, Irani
text
Neotropical Ichthyology
2011
2011-06-30
9
2
281
298
http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252011000200005&lng=en&tlng=en
journal article
10.1590/S1679-62252011000200005
1982-0224
5422500
Lepidocharax
,
new genus
Type
species.
Lepidocharax diamantina
, by original designation.
Diagnosis.
According to our analysis,
Lepidocharax
can be phylogenetically diagnosed from the remaining
Stevardiinae
by the presence of the following autapomorphies supporting clade 4: 1) parhypural and hypural 1 either contacting each other leaving a narrow joint line between them or fused to each other (character 64, state 1), and 2) nasal tubular, without bone expansion (character 96, state 1). Both characters are, however, homoplastically shared among other
Stevardiinae
. Character 64 (state1) also supports clades 10 and 13, and character 96 (state 1) supports clade 16.
In addition, several distinguishing features are useful to diagnose
Lepidocharax
. It can be distinguished from all the other genera of the
Stevardiinae
except
Planaltina
,
Pseudocorynopoma
, and
Xenurobrycon
by having the dorsalfin origin on the same vertical crossing the anal-fin origin. The presence of adnate scales over the ventral caudal-fin lobe distinguishes
Lepidocharax
from
Planaltina
,
Pseudocorynopoma
, and
Xenurobrycon
which have a caudal organ or pouch bordered by modified scales or represented by a single modified pouch scale.
Etymology.
Lepido
, from the Greek, for scales and
charax
,from the Greek
characo
, meaning pointed stake, here used in reference to the characid genus
Charax
, hence a Characid fish.
Lepidocharax
is a name used in reference to the scales covering the ventral caudal-fin lobe. A noun in apposition.