Molecular phylogeny of Asian pipesnakes, genus Cylindrophis Wagler, 1828 (Squamata: Cylindrophiidae), with the description of a new species from Myanmar
Author
Bernstein, Justin M.
0000-0001-6839-8025
aaron.bauer@villanova.edu
Author
Bauer, Aaron M.
0000-0002-5249-3340
aaron.bauer@villanova.edu
Author
Mcguire, Jimmy A.
0000-0002-9562-5585
mcguirej@berkeley.edu
Author
Arida, Evy
0000-0002-7604-390X
eva.arida@gmail.com
Author
Kaiser, Hinrich
0000-0002-0001-9428
chalcopis@yahoo.com
Author
Kieckbusch, Max
0000-0001-9155-8226
max_kieckbusch@yahoo.de
Author
Mecke, Sven
0000-0003-0085-3364
s.mecke@paderborn.de
text
Zootaxa
2020
2020-09-11
4851
3
535
558
journal article
8539
10.11646/zootaxa.4851.3.5
57a67f85-87a0-4069-804a-a1f6ad1e370b
1175-5326
4494210
D24E45E7-BF27-4E5C-B549-482A1CD4EB3D
Cylindrophis slowinskii
sp. nov.
(
Fig. 4
)
Holotype
.
CAS 241554 (field number:
CAS-MHS 26113
), an adult specimen from
Indawgyi Wildlife Sanctuary
in the vicinity of
Lwe Mon Village
, west of
Indawgyi Lake
,
Mohnyin Township
,
Kachin State
,
Myanmar
(ca.
25.1787° N
,
96.2917° E
,
elevation
245 m
), collected by
J.A. Wilkinson
, K.T. Kyaw, and
J.V. Vindum
on
26 July 2008
(
Fig. 4
).
Paratype
.
USNM 590030
(field number:
CAS-MHS 26114
), an adult specimen, collection data as for the holotype
.
Diagnosis.
A species of the genus
Cylindrophis
, identified by a combination of the following characteristics: (1) small size:
297–333 mm
SVL; (2) 17-19-17 dorsal scale rows; (3) 216–220 ventrals; (4) eight subcaudals; (5) 65–69 very narrow diffuse pale ventral blotches that are branching, creating the impression of a diffuse reticulum; and (6) a pale bar running along the posterior border of the prefrontals (
Fig. 4
). These morphological characters are sufficient to distinguish
C
.
slowinskii
from all other species of Asian pipesnakes.
FIGURE 2.
Maximum likelihood (ML) trees of
Cylindrophis
. Yellow and green circles represent bootstrap support values of 70–94 (moderate support) and 95–100 (strong support), respectively. Clades without circles represent bootstrap values of 0–69 (poor support). Scale bars indicate the estimation of nucleotide substitutions per site. For each terminal, a voucher number and political unit (country) are given. For specimens from Indonesia (ID), island localities are additionally provided. A purple star (
★
) represents specimens of the new species described herein.
A
) Concatenated ML phylogeny of
Cylindrophis
using 16S, ND2, and R35 loci. The shaded clade highlights a Wallacean group containing
C
.
isolepis
,
C
.
boulengeri
, and
C
.
yamdena
.
B–D
) ML genealogies using 16S (
B
), ND2 (
C
), and R35 (
D
). Photo credits:
Cylindrophis maculatus
: Ruchira Somaweera
(The Commonwealth Scientific and Industrial Research Organisation/CSIRO);
Cylindrophis
sp. nov.
(holotype designated herein, CAS 241554): Justin M. Bernstein (Rutgers University-Newark);
C. burmanus
: Hla Tun
(photograph registered and archived at CAS: ID: MHS_209);
C. jodiae
: Teo Eng Wah
(University of Malaya);
C. isolepis
: Jimmy A. McGuire
(MVZ);
C. boulengeri
: Sven Mecke
(Naturkundemuseum Paderborn);
C. yamdena
: Ron E. Johnstone
(WAM).
FIGURE 3.
Concatenated (left) and species (right) trees of
Cylindrophis
. Open circles (○) indicate ML bootstrap values of 70–94; filled circles (●) represent ML bootstrap values of 95–100 (concatenated) or PP of 0.95–1 (BEAST). Symbols behind each clade refer to taxa as defined in inset, with symbols for species of the Wallacean clade consistently colored red. In the map, the origins, as political units (countries) or islands, of the specimens used for the phylogenies are shaded, and do not represent the total geographic range of the respective taxon. A purple star (
★
) indicates the type locality of the new species described herein. For country records of all species of
Cylindrophis
, see Fig. 1.
FIGURE 4.
Holotype of
Cylindrophis slowinskii
sp. nov.
(CAS 241554) from Kachin State, Myanmar in dorsal (A) and ventral (B) view. The head is shown in lateral (C) and dorsal (D) view, the tail in ventral view (E). The 10 mm and 5 mm scale bars are for panels A+B and C+D+E, respectively. Photos by Justin M. Bernstein.
Description of the
holotype
.
Metrics
. A relatively short body,
333 mm
SVL +
7 mm
TL =
340 mm
TTL (
336 mm
in life), tail blunt and very short (2% of SVL); BD
7.4 mm
(2.2% of SVL); head not wider than body, HL
7.4 mm
(2.2% of SVL), HW
4.9 mm
(66.2% of BD); snout rounded in dorsal and lateral views, relatively long, 2.7 times as long as diameter of the eye, SL
3.4 mm
(45.9% of HL), SW
2.8 mm
; a small eye, ED
0.9 mm
(12.1% of HL); IOD
3.3 mm
; IND 2.0 mm; rostral height
1.2 mm
, width
1.6 mm
; paired nasals, length of a single nasal
1.1 mm
, width
1.8 mm
; paired prefrontals, length of a single prefrontal
1.6 mm
, width
1.9 mm
; frontal length 2.0 mm, width
1.6 mm
; paired parietals, length of a single parietal
1.7 mm
, width
1.5 mm
; paired supraoculars, length of a single supraocular
1.9 mm
, width
1.5 mm
; postocular length
0.7 mm
, height
0.8 mm
; anterior temporal length
1.2 mm
, height
1.6 mm
, upper posterior temporal length
1.5 mm
, height
0.8 mm
; mental height
0.7 mm
, width
1.3 mm
; two pairs of chin shields, anterior chin shield length
1.8 mm
, width
1.6 mm
, posterior chin shield length
1.5 mm
, width 1.0 mm; mental groove length
3.1 mm
. The
holotype
weighed
12.5 g
in life.
Scale counts and qualitative pholidosis.
17-19-17 dorsal scale rows; 220 ventrals; eight subcaudals + terminal spine; postnasal, loreal, preocular, and subocular absent; temporal formula 1 + 2; six supralabials, 3
rd
and 4
th
contacting the eye; six infralabials; cloacal scute divided; scales on head, trunk, and tail smooth; apical pits absent.
Coloration and pattern in preservative
(
after 11 years in ethanol
). Dorsal surface Jet Black (300), with 31 transverse Pale Buff (1) to Chamois (84) blotches from nape to tail; blotches may be complete or medially interrupted, if interrupted both parts may alternate; first four blotches approximately one scale wide, blotches covering medial part of the body narrowest, covering scale margins only, last dorsal blotch broad, dorsal blotch on the tail Pale Pinkish Buff (3), merging onto the subcaudal region, tail tip dark; a pale bar runs from the border of the prefrontals with the frontal towards the upper margin of the 3
rd
supralabials, leaving the margin of the prefrontals with the supraoculars dark; posterior half of 3
rd
supralabial with a pale blotch, slightly connected with the prefrontal bar on the right side only; margin of 5
th
labial pale; frontal with a pale median blotch; scales on ventral surface of head almost always with pale margins (except for the mental and 1
st
labials); ground color of venter as for dorsum; 69 pale and very narrow diffuse ventral blotches present, branching, and therefore creating the impression of a diffuse reticulum.
Variation.
The
paratype
(USNM 590030) differs from the
holotype
(CAS 241554) as follows (metrics of head scales excluded):
297 mm
SVL +
8 mm
TL =
305 mm
TTL; 216 ventrals; 65 pale ventral blotches. In terms of color pattern, the
paratype
is very similar to the
holotype
. The bar on the prefrontals is not in contact with the pale color of the supralabials on both sides. All supralabials (except for the 1
st
and 2
nd
on the right side) have pale markings.
Comparisons with other species.
Cylindrophis slowinskii
(
n
= 2; characters listed in parentheses below), yet alone differs from all congeners by a combination of unique scalation characters, including 17-19-17 dorsal scale rows, a high number of ventrals (216–220), and eight subcaudals.
Cylindrophis aruensis
possesses 23 (19) dorsal scale rows at midbody, 173−182 (216−220) ventrals, six or seven (eight) subcaudals, 44 (65−69) pale ventral blotches, and pale stripes on the head, running from the nasals onto the posterior temporals (a pale bar on the prefrontals, no pale markings posterior to the eyes) (
Boulenger 1920
;
McDowell 1975
;
Lang 2013
;
Amarasinghe
et al
. 2015
).
Cylindrophis boulengeri
(
n
= 4) possesses 195−204 (216−220) ventrals, five or six (eight) subcaudals, 48−54 (65−69) pale ventral blotches, and pale wavelike markings along the labials that may run onto the prefrontals but are never connected to form a bar (no wavelike markings on the labials, a pale bar on the prefrontals).
Cylindrophis burmanus
(
n
= 20) possesses 190−
2202
[median = 209] (216−220; median = 218) ventrals, four to seven (eight) subcaudals, and 29−61 (65−69) pale ventral blotches.
Cylindrophis engkariensis
(
n
= 1) possesses 17 (19) dorsal scale rows at midbody, 230 (216−220) ventrals, five (eight) subcaudals, rugose (smooth) dorsals on the tail, 45 (65–69) pale ventral blotches, a dorsal pattern of two paravertebral rows of dark spots (transverse pale dorsolateral blotches), a pale postocular streak (no postocular streak), and dark prefrontals (a pale bar on the prefrontals).
Cylindrophis isolepis
(
n
= 2) is a relatively large species with a maximum SVL of
500 mm
(
333 mm
; see
Amarasinghe
et al
. 2015
) and possesses 21 (19) dorsal scale rows at midbody, five or six (eight) subcaudals, nasals that are separated by the rostral (nasals in contact), 27−35 (65–69) pale ventral blotches that are reddish in living specimens, and no markings on the dorsal surface of the head (a pale bar on the prefrontals).
Cylindrophis jodiae
(
n
= 90) is a relatively large species with a maximum SVL of
786 mm
(
333 mm
) and possesses 21 (19) dorsal scale rows at midbody, 177−201 (216−220) ventrals, five to seven (eight) subcaudals, 30−55 (65−69) pale ventral blotches, pale wavelike markings along the labials or heavily blotched labials (labials without prominent pattern), and dark prefrontals (a pale bar on the prefrontals).
Cylindrophis lineatus
(
n
= 1) is a relatively large species with a maximum SVL of
713 mm
(
333 mm
) and possesses 21 (19) dorsal scale rows at midbody, 210−218 (216−220) ventrals, 31 (65−69) pale ventral blotches, a dorsal pattern of stripes that are red and black in living specimens (transverse pale dorsolateral blotches), a pale dorsal surface of head and tail, both being red in living specimens (no extensively colored dorsal surface of head and tail), and dark markings on the temporals and parietals (head uniformly dark with a pale bar on the prefrontals) (see also
Amarasinghe
et al.
2015
).
Cylindrophis maculatus
(
n
= 36) possesses 27−49 (65−69) pale ventral blotches, a dorsal pattern of large and roundish, paired pale blotches separated by a narrow dark network, with the blotches being reddish-brown in living specimens (very narrow and widely separated transverse pale blotches on a dark dorsum), and prefrontals that lack a pale bar (a pale bar on the prefrontals).
Cylindrophis melanotus
(
n
= 39) is a relatively large species with a maximum SVL of
678 mm
(
333 mm
) and possesses 228−268 (216−220) ventrals and 38−63 dark blotches on a pale-colored venter that is reddish or white in living specimens (65−69 very narrow diffuse pale blotches on a dark-colored venter).
Cylindrophis opisthorhodus
(
n
= 6) possesses 23 (19) dorsal scale rows at midbody, 185−210 (216−220) ventrals, four to seven (eight) subcaudals, 46−61 (65−69) pale ventral blotches, a pale dorsum with dark speckles forming two paravertebral rows and occasionally a discontinuous vertebral line (very narrow transverse pale blotches on a dark dorsum), and dark speckles on the pale dorsal surface of the head (head uniformly dark with a pale bar on the prefrontals) (see also
Amarasinghe
et al.
2015
).
Cylindrophis osheai
(
n
= 3) possesses 224–226 (216–220) ventrals, 25−28 dark ventral blotches, aligned to form a broad wavy stripe along most of the otherwise pale underside (venter almost entirely black with 65–69 diffuse pale blotches), and no pale bar on the prefrontals (a pale bar on the prefrontals).
Cylindrophis ruffus
(
n
= 244), as defined by
Kieckbusch
et al.
(2016)
, is a relatively large species with a maximum SVL of
857 mm
(
333 mm
) and possesses five to seven (eight) subcaudals and 33−66 (65–69) pale ventral blotches.
Cylindrophis subocularis
(
n
= 9) possesses a subocular scale (no subocular scale), 190−196 (216−220) ventrals, six or seven (eight) subcaudals, and 40−48 pale ventral blotches that are usually as broad as the dark blotches (65–69 very narrow diffuse pale blotches that are widely separated by dark color).
Cylindrophis yamdena
(
n
= 5) is a relatively large species with a maximum SVL of
671 mm
(
333 mm
) and possesses 21 (19) dorsal scale rows at midbody, 183−195 (216−220) ventrals, and no pattern on the dorsal surface of the body and no ventral blotches in adults (a pale bar on the prefrontals, pale blotches on the dorsum and venter).
2 Among the
20 specimens
of
Cylindrophis burmanus
we have examined, only a single specimen (BMNH 1908.6.23.3;
paralectotype
) has a ventral count (= 220) that falls within the range of
C
.
slowinskii
. The second highest count in our specimens was 214 ventrals. BMNH 1925.12.22.4 (
paralectotype
) was stated to possess 225 ventrals by
Amarasinghe
et al
. (2015)
, but has only 214 ventrals (see also
Wall (1926)
, who provided a count of 212 ventrals for this specimen).
Geographic distribution, habitat, and natural history.
Cylindrophis slowinskii
might have a more isolated distribution with regard to the other species of the genus and is only known from its
type
locality in northern
Myanmar
near Indawgyi Lake (
Fig. 5
). As the
type
specimens were found under logs in forests,
C. slowinskii
is assumed to be a secretive forest-dweller with a semi-fossorial lifestyle, as typical for most species of Asian pipesnakes. Due to the limited number of available specimens, the complete geographic distribution and biogeographic history of
C
.
slowinskii
is uncertain. However, the physiography of northern
Myanmar
, especially
Kachin State
, is characterized by scattered stretches of mountains that may act as dispersal and gene flow barriers for species of
Cylindrophis
. Additionally, major rivers such as the
Irrawaddy
River, and its largest tributary, the Chindwin River, may also largely act as barriers to gene flow. These biogeographic hypotheses, however, can only be tested using more complex analyses, divergence dating estimates, and a more complete sampling of
C. slowinskii
and the closely related
C
.
burmanus
(see “Remarks on the
type
series”, below).
Etymology.
The specific epithet is a patronym to honour the American herpetologist Joseph Bruno “Joe” Slowinski (1962–2001) and his pioneering work on herpetofauna, especially in
Myanmar
. In 2001, Joe led a multidisciplinary expedition to
Kachin State
,
Myanmar
, the
type
locality of the new species described herein. For biographical details see
Donnelly & Crother (2003)
and
James (2008)
.
Suggested common names.
Slowinski’s pipesnake (English), Slowinski-Walzenschlange (German),
Remarks on the type series of the closely allied
Cylindrophis burmanus
.
The Asian pipesnake
Cylindrophis burmanus
was originally described as a subspecies of “
C
.
ruffus
” by Malcolm Arthur Smith (1875–1958) based on an unspecified number of vouchers. The distributional range of this new taxon was given as “Tenasserim and
Burma
as far North as Myitkyina” (today’s
Myanmar
) without the restriction of a precise type locality.
Amarasinghe
et al
. (2015)
designated a
lectotype
(BMNH 1940.3.3.1) from “the presumed type series” (i.e., the
syntypes
) and listed five additional specimens housed in the collection of the BMNH that they designated as
paralectotypes
(see also
Kieckbusch
et al
., 2016
).
Although
Smith (1943
; probably based on
Wall (1925))
listed Tenasserim, today’s
Tanintharyi Region
, as the southern limit for the distribution of
Cylindrophis burmanus
, we were not able to confirm the presence of this species south of the
Irrawaddy
Delta based on voucher specimens. A single, more recent record (JMB & SM, pers. obs.) for an Asian pipesnake from the
Tanintharyi Region
can be identified as
C
.
jodiae
.
The
lectotype
(definitive type) of
Cylindrophis burmanus
was collected from
Yangon
(today’s
Rangoon
; see
Fig. 5
), the most famous port in the
Irrawaddy
Delta, and capital of all
Myanmar
(
Burma
) from 1886 to 2005. Based on its collection locality, this specimen likely belongs to the population that is found in the
Irrawaddy
Delta and east of the
Irrawaddy
River and that we identified using molecular genetic methods (
Fig. 5
). Among all the vouchers of
C
.
burmanus
we have examined (
n
= 20; see “Appendix 2”), only a single specimen (BMNH 1925.12.22.4;
paralectotype
) was collected from the temperate hilly zone in northern
Myanmar
that is enclosed by the Chindwin and
Irrawaddy
Rivers (see
Wall (1926))
, and only ~
50 km
away from the type locality of
C
.
slowinskii
, the latter located at the western side of Indawgyi Lake. Indawgyi Lake is enclosed by hilly country as well, with the Loipyet Range acting as a potential barrier to the east. The collection locality of BMNH 1925.12.22.4 (Sahmaw; part of the Myitkyina District when the specimen was collected) is located in the lowlands east of this mountain range. Based on morphology (214 ventrals, seven subcaudals, 52 pale ventral blotches) this
paralectotype
identifies as
C
.
burmanus
.