Synopsis of the terrestrial Reptiles of Equatorial Guinea
Author
Sánchez-Vialas, Alberto
Author
Calvo-Revuelta, Marta
0000-0002-8628-1055
Author
Riva, Ignacio De La
0000-0001-5064-4507
albertosv@mncn.csic.es
text
Zootaxa
2022
2022-11-03
5202
1
1
197
http://dx.doi.org/10.11646/zootaxa.5202.1.1
journal article
182444
10.11646/zootaxa.5202.1.1
45ba25c1-47a9-4001-93d9-294815bf37e7
1175-5326
7285600
BF4831D2-D98B-4265-9138-03DB8607B826
Afrotyphlops congestus
(
Duméril & Bibron, 1844
)
Figure 31A–B
Onychocephalus congestus
Duméril & Bibron, 1844: 334
.
Type
locality: unknown.
Onychophis barrowii
Gray, 1845: 133
.
Type
locality: “
India
?” (in error
fide
Hahn 1980: 68
).
Typhlops crassatus
Peters, 1881c: 50
.
Type
locality: “Chinchoxo, durch die africanische Gesellschaft” (=
Cabinda
,
Angola
).
Rhinotyphlops congestus
(
Duméril & Bibron, 1844
)
: Broadley & Wallach 2000: 167.
Afrotyphlops congestus
(
Duméril & Bibron, 1844
)
:
Broadley & Wallach 2009: 46
.
Distribution
. It extends from southeastern
Nigeria
to the West of
Uganda
, southward to the
Republic of the Congo
. In
Equatorial Guinea
it has been recorded in Bioko at Basilé (
Bocage 1895a
;
Bocage 1903
;
Roux-Estève 1974
) and Moka (
Mertens 1964a
), and in
Río Muni
at Monte Alén National Park (
Lasso
et al.
2002
) (
Map 36A
).
Comments.
Afrotyphlops congestus
was formerly considered by some authors as a subspecies of
A. punctatus
(
Leach, 1819
)
(
Werner 1913
;
Roux-Estève 1974
; see
Broadley & Wallach 2009
). Some molecular works that included samples of both taxa, supported their independent species status (
Vidal
et al.
2010
;
Hedges
et al.
2014
;
Pyron & Wallach 2014
;
Nagy
et al.
2015
). In Wallach
et al
’s. (2014) catalogue,
A. punctatus
is included in the fauna of Bioko, maybe as a result of a mistake coming from the previous status of
A. congestus
as a subspecies of
A. punctatus
. Taking into account (1) the high morphological similarity shown by
A. punctatus
and
A. congestus
, and (2) the ecology of these two species, in which
A. punctatus
usually occurs in savannah environments (
Trape & Baldé 2014
) whereas
A. congestus
exclusively inhabits forests, we follow
Roux-Estève (1974)
in considering all the populations from
Equatorial Guinea
(both Bioko and
Río Muni
) as
A. congestus
, excluding
A. punctatus
from the reptile list of the country.
Afrotyphlops congestus
, like some other related species [e.g.
A. punctatus
,
A. liberiensis
(Hallowell, 1848)
], presents two phenotypes, a “marbled” form and a “striped” form, the first one being more common in
A. congestus
(
Roux-Estève 1974
)
. Mertens (1964) reported the striped phenotype of
A. congestus
in Moka, Bioko. We found both phenotypes among the examined specimens either from
Río Muni
or Bioko: MNCN23354, MNCN23355, MNCN23357, EBD 20801, 27520, 24963 depict a marbled pattern, whereas MNCN23356 and EBD 2843 show a striped pattern. The pholidosis traits of the examined specimens fall within the variability of the species [midbody scale rows: 28 (MNCN23356), 31 (MNCN23357), and 30 (MNCN23354, MNCN23355); number of dorsal longitudinal scales: 332 (MNCN23356), 333 (MNCN23357), 383 (MNCN23355), 394 (MNCN23354)]. The examined specimens from
Río Muni
present a greater number of dorsal longitudinal scales (383–394) than the Biokoan examined specimens (332–333).
There is a taxonomic question dealing with the striped phenotype, pending resolution until more data are available. Some putative undescribed species of
Afrotyphlops
are shown by
Chirio & LeBreton (2007)
. For example, the one named “
Rhinotyphlops
sp.3
”, is morphologically similar to some striped specimens of
A. congestus
. These authors noted the same pholidotic pattern in their undescribed form “
Rhinotyphlops
sp.3
” and in
A. congestus
. A molecular phylogeography including both the “marbled” and “striped” phenotypes of
A. congestus
,
together with samples of specimens assignable to the putative new taxa depicted by
Chirio & LeBreton (2007)
will be required in order to resolve this taxonomic conundrum. With the data at hand, we tentatively consider all the examined striped specimens as
A. congestus
.
Specimens examined.
Eight
specimens.
Río Muni
: without specific locality, 1885 (
MNCN 23354–23355
)
.
Nvom (road from Aconibe to Asoc),
08April 1987
(
EBD
24963)
.
Miboman (road from Movo to Niefang),
September 1987
(
EBD
27520)
.
Miboman (Km 27, road from Bata to Movo),
02 June 1986
(
EBD
20801)
.
Enuc
,
12 April 1965
(
EBD 2843
)
.
Bioko
: without specific locality, 1876–1877 (
MNCN 23356–23357
)
.