Taxonomic revision of Drymoluber Amaral, 1930 (Serpentes: Colubridae)
Author
Costa, Henrique Caldeira
Author
Moura, Mário Ribeiro
Author
Feio, Renato Neves
text
Zootaxa
2013
3716
3
349
394
journal article
10.11646/zootaxa.3716.3.3
9a8c1b4f-0173-482f-8eb1-ff7e106549a6
1175-5326
249295
71B98313-E0FC-427D-A06F-6917B64A64F8
Drymoluber apurimacensis
Lehr, Carrillo & Hocking, 2004
Drymoluber apurimacensis
Lehr, Carrillo & Hocking, 2004
.
Copeia,
2004, p. 47.
Holotype
:
Museu de Historia Natural Universidad Nacional Mayor de San Marcos, MHNSM 20672, juvenile female, SVL
206 mm
, TL
73 mm
, collected by P. Hocking on
15 January 2001
, in Abancay (-13.64, -72.88), Abancay Province, Apurimác Department,
Peru
,
2500 m
above sea level (Lehr
et al.
2004). Specimen examined by photographs (
Fig. 22
).
Paratypes
:
Field Museum of Natural History, FMNH 81542, male, SVL
460 mm
, TL
192 mm
, collected by C. Kalinowski in
September
1953
in Hacienda Palmira (-13.65, -73.38), Huancarama district, Andahuaylas Province, Apurimác Department,
Peru
,
3300 m
above sea level (specimen examined by the senior author;
Fig. 23
A); Museum für Tierkunde, Dresden, MTKD 44669, adult female, SVL
653 mm
, TL
253 mm
, killed by a local farmer in
May 2002
, in Cconoc (-13.06, -72.64), Abancay Province, Apurimác Department,
Peru
,
1925 m
above sea level (Lehr
et al.
2004) (specimen examined by photographs;
Fig. 23
B); MHNSM 18647, female, SVL
670 mm
, TL
274 mm
(Lehr
et al.
2004; not examined), MTKD 45192, male, SVL
480 mm
, TL
165 mm
(Lehr
et al.
2004; examined by photographs;
Fig. 23
C), MTKD 45193, female, without head, TL
216 mm
(Lehr
et al.
2004; examined by photographs;
Fig. 23
D), all collected by an inhabitant of Cconoc, Abancay Province, Apurimác Department,
Peru
,
1925 m
above sea level (Lehr
et al.
2004).
Diagnosis:
Drymoluber apurimacensis
is distinguished from
D. brazili
and
D. dichrous
by the following combination of characters:
a)
13-13-13 dorsal scale rows without apical pits;
b)
158–164 ventrals in males,
166– 182 in
females;
c)
84–93 subcaudals in males,
87–91 in
females;
d)
14–16 maxillary teeth.
Comparisons:
Drymoluber brazili
has 17-17-15 dorsal scales rows, and
D. dichrous
has 15-15-15. Apical pits are present in
D. brazili
and
D. dichrous
.
Drymoluber brazili
has 182–200 ventrals in males and
185–202 in
females, 109–127 subcaudals in males and
109–126 in
females.
Drymoluber dichrous
is not distinguishable from
D. apurimacensis
based on ventrals and subcaudals counts, having 157–173 ventrals in males and
160–180 in
females, 87–110 subcaudals in males and
86–109 in
females.
Drymoluber brazili
has 19–15 maxillary teeth, and
D. dichrous
has 19–16.
FIGURE 22.
Holotype of
Drymoluber apurimacensis
Lehr, Carrillo & Hocking, 2004
(MHNSM 20672). Photo: Claudia P. Torres Gastello.
The only known juvenile of
Drymoluber apurimacensis
(
holotype
) has dark crossbands 1–2 scales wide, and pale interspaces 2–3 scales wide. Juveniles of
D. brazili
have dark crossbands 2–6 scales wide (mean 3.6) and pale interspaces 0.5–5 scales wide (mean 1.6). Juveniles of
D. dichrous
have dark crossbands 1.5–7 scales wide (mean 3.6) and pale interspaces 0.5–2.5 scales wide (mean 0.8).
The hemipenis of
Drymoluber apurimacensis
has more calyces than those of
D. brazili
, smaller spinulate flounces, and no spines in the lobular region. The walls of the sulcus spermaticus tend to be more ornamented, at least in the lobular region, with small jagged papillae. The spines on the asulcate face, mainly the most proximal, are larger than those in some specimens of
D. brazili
. The hemipenial morphology of
D. apurimacensis
and
D. dichrous
is similiar, making inaccurate the differentiation of these species by hemipenial characters.
According to the description by Lehr
et al.
(2004),
Drymoluber apurimacensis
has dorsal scales with two apical pits. However, a reexamination of the
holotype
and four
paratypes
did not reveal apical pits (H.C. Costa pers. obs.; M. Auer, pers. comm.; C.P. Torres-Castello, pers. comm.). Lehr
et al.
(2004) also suggested that
D. apurimacensis
could de distinguished from its congeners based on the temporal formula of 1+2 (1+1/
1 in
the present study), while
D. brazili
and
D. dichrous
have temporal formulae of 2+2 (1/1+1/
1 in
the present study).
As
previously discussed, marked polymorphism of temporal plates characterizes
Drymoluber
, and the temporal formula 1+1/1 also occurs in
D. dichrous
and
D. brazili
, although the 1/1+1/1 formula is more frequent.
Coloration of preserved adults:
Three of the four
paratypes
examined (MTKD 44669, 45192, 45193) have the dorsum covered with old scales of olivre-brown color. The inner layer of scales is light bluish-gray. The labials, gular region and the venter are cream colored. The venter becomes bluish-gray with some cream marks on the posterior 2/3 of the body. Subcaudals are bluish-gray and cream colored.
FIGURE 23.
Four of the five paratypes of
Drymoluber apurimacensis
Lehr, Carrillo & Hocking, 2004
. A) FMNH 81542; B) MTKD 44669; C) MTKD 45192; D) MTKD 45193. Photos: Henrique C. Costa (A) and Barbara Bastian (B–D).
The coloration of FMNH 81542 is darker; its dorsum is dark-gray, and the venter is cream on the anterior third, becoming gray with cream marks posteriorly. The supralabials are cream with dark upper and lateral edges (the last four scales are almost completely black), and the gular region is cream.
There is no information about the coloration of living adult specimens of
D. apurimacensis
.
Coloration of preserved juveniles:
The only known specimen of
D. apurimacensis
with juvenile coloration is the
holotype
(MHNSM 20672). Its dorsum has more than 40 dark crossbands of uniform size (about 1–2 scales wide), which become less visible in the posterior third of the body. The light interspaces are 2–3 scales wide. The gular region and venter are cream to light-gray color. The dark crossbands reach the lateral edges of ventrals. The head has the same color of the juveniles of
D. dichrous
and
D. brazili
with a transversal white stripe crossing the parietals. The supralabials are pale colored, with slightly darkened lateral edges.
Coloration of juveniles in life:
The
holotype
had black crossbands, and the interspaces are brown. The venter was light-gray and the head brown with black marks (Lehr
et al.
2004).
Hemipenial morphology (n=1) (
Fig. 24
):
Hemipenis single, subcylindrical, not capitate. Sulcus spermaticus single and centrolinear. Lobe with just less than half of the hemipenis length, with papillate calyces (5–10 triangular papillae per calyx). Proximally, the calyces are gradually replaced by spinulate flounces and spines. Body covered by spines arranged in more or less transverse rows (about 60–70 spines in total). Walls of the sulcus spermaticus ornamented at least in the lobular region by jagged papillae and some spinules. These walls are also bordered on both sides by a longitudinal row of eight spines that tend to increase in size toward the proximal region. A hook is present at the end of each of row bordering the sulcus; the right hook is located more proximally than the left. Neither spines nor spinules occur between the left hook and the sulcus spermaticus. There are two lateral spines larger than the hooks left of the sulcus. The asulcate face of the hemipenis is formed by spines arranged in about seven more or less transverse rows (counted from proximal to distal region), with largest spines in the medial rows. The base of the hemipenis is smooth, with some grooves and several sparse spinules.
Variation:
When available, data of the
paratype
MHNSM 18647 given by Lehr
et al.
(2004) were used. Largest male has SVL
643 mm
, TL
253 mm
(MTKD 44669); largest female has SVL
670 mm
, TL
274 mm
(MHNSM 18647; not examined). The tail is 34.4–41.7% of the SVL in males (mean 38.5%; SD=3.75; n=3) and 35.4–40.9% (n=2) in females. For variation in meristic characters, see
Table 5
.
Geographic distribution:
Drymoluber apurimacensis
is known from three localities between 1920 and 3300 meters above sea level south of the Apurimác and Pampas Rivers, department of Apurimác, in the Serranía Esteparia ecoregion. The area is characterized by
matorral seco
and
matorral sub-húmedo
vegetation (Lehr
et al.
2004).
Drymoluber apurimacensis
probably is endemic to the deep valley of the Apurímac River, which seems to be a significant geographical barrier to the North-south distribution of some Andean taxa (Lehr
et al.
2004). Amphibians of the genus
Bryophryne
(Strabomantidae)
, the bird
Synallaxis courseni
(Furnariidae)
and the plant
Solanum anomalostemon
(Solanaceae)
are some species endemic to the Apurímac region (Lehr & Catenazzi 2008; BirdLife International 2009; Knapp & Nee 2009).
Natural history:
The
holotype
was collected under a rock at midday, and the
paratype
MTKD 45193 had a lizard
Euspondylus
sp. (
Gymnophthalmidae
) in its stomach (Lehr
et al.
2004).
Drymoluber apurimacensis
is sympatric with the snakes
Dipsas peruana
,
Leptotyphlops
sp.,
Oxyrhopus melanogenys
and
Tachymenis peruviana
(Lehr
et al.
2004)
.