Description of a new annual rivulid killifish genus from Venezuela
Author
Hrbek, Tomas
Author
Taphorn, Donald C.
text
Zootaxa
2008
1734
27
42
journal article
10.5281/zenodo.181425
65266d45-ee92-4b56-994c-a3254b00a608
1175-5326
181425
Llanolebias
new genus
Fig. 4
(male and female),
Fig. 5
(male and female MCNG 25828)
Type
species.
Rivulus stellifer
Thomerson & Turner 1973
.
Holotype
:
USNM
209254;
Paratypes
:
USNM
209254,
FMNH
71667,
FMNH
71668,
UMMZ
193375,
CAS
27556,
MBUCV
V-
7199, ICNMHN 700.
FIGURE 4.
A representative female (4a) and male (4b)
Llanolebias stellifer
(photos by Tonnie Woeltjes).
Diagnosis.
Llanolebias
is diagnosed by the numerous molecular characters, however, it possesses no unique morphological characters that will unambiguously distinguish it from all other rivulid species; however, 13 characters distinguishing it from the genus
Rachovia
, and 33 characters distinguish it from the genus
Gnatholebias
. Compared to its sister genus
Gnatholebias
, the single species of
Llanolebias
is a robust, cylindrical-shaped fish, with short fins and in males very small fin-ray extensions, while
Gnatholebias
species have relatively deep, laterally compressed bodies with long fins and long fin-ray extensions. The anal fin base of
Llanolebias
is also short compared to species of
Gnatholebias
, and
Llanolebias
has 14-15 anal fin rays versus 22-26 fin rays in
Gnatholebias
.
Llanolebias
also lacks the fatty predorsal ridge characteristic of older males of
Rachovia
. With the sole exception of females of
Renova oscari
Thomerson & Taphorn, 1995
,
Llanolebias
is the only member of the ‘lowland annual’ clade of
Rivulidae (
Hrbek & Larson, 1999
)
with a ‘Rivulus’ spot in females.
Llanolebias stellifer
also differs ecologically from the two species of
Gnatholebias
.
Llanolebias stellifer
occurs in shallow habitats on the edges of aquatic systems in deep forest, whilst
Gnatholebias zonatus
is from sunny pools in the savannah and
Gnatholebias hoignei
(Thomerson, 1974)
is from shaded but deeper pools than
L. stellifer
.
Llanolebias stellifer
is confined to seasonally wet areas in the seasonally dry tropical forest region of the Llanos, and is found in a habitat similar to that occupied by species of the genera
Aphyolebias
and
Moema
which are found in seasonally wet areas of dense tropical forests of the Amazon and
Essequibo
basin.
Included taxa.
Only the
type
species.
Etymology.
From the Spanish
Llanos
(grassy plains, and in particular the Orinoco River savannahs of
Venezuela
and
Colombia
) and the Greek
Lebia
(a small fish and a nominal cyprinodontiform genus). Gender masculine.