Alpine-Himalayan orogeny drove correlated morphological, molecular, and ecological diversification in the Persian dwarf snake (Squamata: Serpentes: Eirenis persicus)
Author
Rajabizadeh, Mahdi
Author
Nagy, Zoltán T.
Author
Adriaens, Dominique
Author
Avci, Aziz
Author
Masroor, Rafaqat
Author
Schmidtler, Josef
Author
Nazarov, Roman
Author
Esmaeili, Hamid Reza
Author
Christiaens, Joachim
text
Zoological Journal of the Linnean Society
2016
176
878
913
journal article
10.5281/zenodo.5360449
0024-4082
5360449
591555C6-EF37-495B-A
CONTIA PERSICA
PERSICA
TERENT ÉV & CHERNOV, 1965
Holotype
Adult male,
ZDEU 136
/2005, legit.
İ. Baran
,
Y. Kumlutas
¸,
Ç. Ilgaz
, and
A. Avcı
,
01.v.2005
.
Paratypes
Twenty-two specimens. See Appendix 1.
Terra typica
Between
Diyarbakır
and
Siverek
,
48 km
west of
Diyarbakır
(
37°49′12.3″N
,
39°37′58.5″E
), S¸ anlıurfa
Province
,
Turkey
(locality indicated by circle
7 in
Fig. 2
).
Altitude
1100 m
a.s.l.
Diagnosis
Eirenis occidentalis
sp. nov.
is differentiated from all other congeners by having the unique combination of 186–213 ventrals in
♂
and
204–224 in
♀
; 46–59 subcaudals in
♂
and
42–58 in
♀
; ratio of the tail length over total length
13.43–19.49 in
♂
and
13.05–18.99 in
♀
; usually seven, rarely eight, infralabials; unicoloured dorsum, anterior dorsal scales without dark base.
Description of the
holotype
Body cylindrical; head small and not distinct from the neck; head and body scales not keeled; rostrum
0.98 mm
high and
2.10 mm
wide, bordered by two upper labials, two nasals, and two internasals; rostrum slightly curved towards top of the head and does not quite intrude between the internasals; nostrils situated on the nasal scales at either side; distance between the nostrils
2.44 mm
; loreal absent; single preocular and postocular on each side of the head; eyes small, with circular pupil of
0.96 mm
diameter; length of the narrow frontal
2.30 mm
, width
1.54 mm
; seven upper labials, third and fourth in contact with the eyes on each side; seven infralabials on each side; three pairs of infralabials in contact with the anterior chin shields at the left side and four at the right side; one anterior temporal and one posterior temporal on each side; ten dorsals plus temporal scales surrounding the posterior margin of the parietals; 15 dorsal scale rows at mid body, 17 at the level of one head length posterior to the head, and 15 at one head length anterior to the level of anus; two anal plates; two gular scales in contact with the posterior chin shield; 209 ventrals, 46/46 + one subcaudals; pileus length
7.62 mm
, width
4.26 mm
; head height
3.66 mm
; snout–vent length
313.68 mm
, tail length
48.66 mm
.
The background colour of the head and the dorsum in the living specimen is reddish brown, changing to yellowish or light brown in the preserved specimen, dorsum without pattern; blackish marking over the dorsal head, connected to a 5–6-scale-wide blackish band on the nape; dorsal marking extends to both sides of the head, reaching the nasals, four upper labials (1– 4), around the eye, the postoculars, and the upper side of the temporals; a narrow black blotch extends from the upper part of the first sublabial to the contact of the third; a straight collar band can be seen over the lower part of the head; length of collar band 19 scales, not connected ventrally; the venter and the lower part of the tail uniformly cream, without maculation (
Fig. 14
).
Variation
The
paratypes
agree in external morphology with the
holotype
. Detailed data on the
paratypes
(
N
= 21;
7♂
,
14♀
) and the single
holotype
are given in Appendix 3.
Dorsal background colour in preserved specimens yellowish or light brown, without dorsal pattern; black- ish marking on the dorsal head and a 4–7-scale-wide blackish band on the nape, usually separated from each other by a narrow light band crossing the tip of the parietals or connected to each other medially; the lateral head and the labials may be uniformly cream or the dorsal head marking may extend to the snout, the anterior or around eyes, adjacent supralabials or infralabials and upper margin of the temporal region; lower side of the head uniformly cream; the width of the nape’s band shrinks over the lateral sides of the neck and are detached over the ventral side.
Comparisons
This new species is distinguished from
E. persicus
by having a higher average number of ventrals, 186– 213 (
x
= 199.78) in
♂
and 204–224 (
x
= 211.29) in
♀
[compared with 190–203 (
x
= 195.6) in
♂
and 198–214 (
x
= 205.0) in
♀
in the latter species]; a lower average number of subcaudals, 46–59 (
x
= 51.89) in
♂
and 42–58 (
x
= 51.23) in
♀
[compared with 64–83 (
x
= 75.0) in
♂
and 54–77 (
x
= 66.25) in
♀
in
E. persicus
] and a lower average ratio of the tail length over the total length, 13.43–19.49 (
x
= 16.30) in
♂
and 13.05–18.99 (
x
= 15.65) in
♀
[compared with 21.93– 29.09 (
x
= 23.80) in
♂
and 18.92–22.60 (
x
= 20.42) in
♀
in
E. persicus
]; usually seven (78.3%), rarely eight, infralabials [compared with usually eight (88.9%), rarely seven]. The new species has a unicoloured dorsum and anterior dorsal scales without dark bases, which is different to
E. nigrofasciatus
,
E. walteri
, and
E. angusticeps
(
nigrofasciatus
morph in
E. nigrofasciatus
, and both
persicus
morph, the anterior dorsal scales having dark bases, and the
walteri
morph in
E. walteri
and
E. angusticeps
). The new species also differs from
E. nigrofasciatus
,
E. walteri
, and
E. angusticeps
in having a lower number of subcaudal scales,
42–59 in
both sexes (compared with
67–96 in
E. nigrofasciatus
,
80–104 in
E. walteri
, and
77–85 in
E. angusticeps
).
Eirenis occidentalis
sp. nov.
differs from
E. mcmahoni
in having 15 anterior dorsal scales (compared with
13 in
E. mcmahoni
).
Eirenis occidentalis
sp. nov.
can be distinguished from the other species of the genus
Eirenis
by having 15 rows of dorsal scales at the mid body and usually no loreal scales (see
Mahlow
et al
., 2013
).
Distribution
Occurs in south-eastern
Turkey
(eastern Taurus Mountains and foothills) up to
Kermanshah province
in western
Iran
(localities indicated by circles
1 to 17 in
Fig. 2
).
Etymology
The name ‘occidentalis’ (Latin: ‘western’) indicates the westernmost known distribution of the taxon amongst the known species within the subgenus
Pseudocyclophis
.