Range extension and extended diagnosis of Lycodon pictus: First country record from China
Author
Janssen, Helen Yvonne
Cologne Zoological Garden, Riehler Strasse 173, D- 50735 Cologne, Germany & Institute of Zoology, University of Cologne, Zülpicher Strasse 47 b, D- 50674 Cologne, Germany
Author
Jin-Long, Ren
Chengdu Institute of Biology, Chinese Academy of Sciences, No. 9 Section 4, Renmin Nan Road, Chengdu, Sichuan, P. R. China, 610041
Author
Jia-Tang, Li
Chengdu Institute of Biology, Chinese Academy of Sciences, No. 9 Section 4, Renmin Nan Road, Chengdu, Sichuan, P. R. China, 610041
Author
Zeng, Wang
Chengdu Institute of Biology, Chinese Academy of Sciences, No. 9 Section 4, Renmin Nan Road, Chengdu, Sichuan, P. R. China, 610041
Author
Nguyen, Tao Thien
Vietnam National Museum of Nature, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Road, Hanoi, Vietnam
Author
Nguyen, Truong Quang
Institute of Ecology and Biological Resources, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet, Cau Giay, Hanoi, Vietnam & Graduate University of Science and Technology, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet, Cau Giay, Hanoi, Vietnam
Author
Bui, Quynh Thi Thuy
Author
Ngo, Hanh Thi
Author
Le, Minh Duc
Author
Ziegler, Thomas
Cologne Zoological Garden, Riehler Strasse 173, D- 50735 Cologne, Germany & Institute of Zoology, University of Cologne, Zülpicher Strasse 47 b, D- 50674 Cologne, Germany
text
Revue suisse de Zoologie
2020
127
2
413
422
journal article
122383
10.35929/RSZ.0030
91ed6259-fe71-4f11-a86b-7b6864d6f217
0035-418
5743934
Lycodon pictus
Janssen, Pham, Ngo, Le, Nguyen &
Ziegler, 2019
Figs 1-3
New record for
Vietnam
(n = 1):
VNMN 011227
(
Fig. 1
), Ha Lang,
Cao Bang
,
Vietnam
,
Coordinates
22°42’50’’ N, 106°40’74’’ E,
960 m
a.s.l., collected by
Nguyen Quoc Huy
on
18 May 2019
.
Fig. 1. The new record of
Lycodon pictus
(VNMN 011227) from Vietnam in life. Photograph by Tao Thien Nguyen.
New record for
China
(n = 1):
CIB 115609
(field no. GX2019069;
Figs 2-3
),
Nonggang National Nature Reserve
,
Longzhou County
,
Guangxi Zhuang
Autonomous Region
, China,
106°57’18.77” E
,
22°28’3.92” N
,
233 m
a.s.l., collected by
Ren Jin-Long
and
Zeng Fan-Xing
on
8 July 2019
.
Description of the Chinese specimen:
Head elongate, moderately distinct from neck, rather flattened, longer than wide, snout narrow, distinctly shorter than head width; nostril large, lateral, located in the middle of the nasal; eye large, pupils vertically elliptic; rostral triangular, much broader than high, hardly visible from above; nasal divided, narrowed medially; two internasals, anteriorly round, slightly wider than high, bordered by two large, hexagonal prefrontals posteriorly; frontal single, enlarged, pentagonal to hexagonal, narrowed posteriorly; parietals large, longer than wide, in contact with each other medially, with upper anterior and posterior temporals, paraparietal laterally and four nuchal scales posteriorly; paraparietals elongated, anterior part widened, about equal in length or slightly longer than posterior temporals; loreal 1/1, elongate, not entering orbit on right side, whereas the posterior corner entering orbit on the left side (
Fig. 3C and D
); supralabials 8/8, first and second in contact with nasal, third to fifth entering orbit, sixth largest, slightly higher than third on left side; infralabials 10/9, first pair in broad contact with each other, first to fifth/first to fourth in contact with anterior pair of chin shields; anterior and posterior pairs of chin shields elongate, second pair not meeting in midline; preocular 1/1, located on antero-upper part of eye; postoculars 2/2, lowermost smaller, bordering anterior temporals; anterior temporal 1/1, in contact with sixth supralabial; posterior temporals 3/3, upper one thinner than lower one. Left maxilla arched, with an angular apex, distinctly bent inwards anteriorly. A total of 13 maxillary teeth or teeth alveola, with the following formula: five small anterior teeth, slightly enlarged posteriorly + three strongly enlarged teeth, thick, and not much curved + a distinctly wide gap + three small teeth + a small gap + two enlarged posterior teeth.
Body elongate, TL
591 mm
; SVL
467 mm
; TaL
124 mm
; preventral 1, ventrals 218, from behind neck region distinctly notched laterally; subcaudals 90, paired; precloacal plate single; DSR 17-17-15, all smooth; the vertebral scales not enlarged.
Coloration in preservative:
Dorsal surface of head and neck with pigmentation, paler on lateral side of head, the lower part of supralabials yellowish cream, speckled with pale brownish blotches. Body brownish black, light body bands beginning after 1.5 times the head length behind the head, in total 29 transverse light bands on body and 14 light bands on tail; the first four body bands yellowish cream, and distinctly widened towards the venter, increased in size posteriorly; a dark mottling in the vertebral region more prominent posteriorly; the subsequent light body bands with two distinct indentations on each side, fused in the middle in the last third of the body.
Fig. 2. New country record of
Lycodon pictus
(CIB 115609) from China (Nonggang, Guangxi), adult female in life. Photograph by Jin-Long Ren.
Fig. 3. Adult female of
Lycodon pictus
(CIB 115609; Guangxi, China) in preservative. (A) Dorsal general view; (B) Ventral general view; (C) Lateral head view, right side; (D) Lateral head view, left side; (E) Dorsal view of head; (F) Ventral view of head; (G) Lateral body view; (H) Ventral scale view. Scale bar 5 mm.Photographs by Jin-Long Ren.
Ventral surface of head and neck yellowish cream, belly cream and greyish cream in the last third part of body and on lower tail surface; the dark dorsal bands in part extending towards the venter, forming complete dark bands around the posterior body and on the tail; lateral side of the head cream below, with the lighter pattern beginning in the supralabial region; tip of lower jaw and infralabial region in part greyish brown; dorsal surface of the head and upper head sides a bit paler than the remaining head dorsum.
Variation of the new specimens:
The Chinese specimen (CIB 115609) largely matches the morphological data of the original description of
Lycodon pictus
, except for having (1) a slightly shorter tail, TaL/TL 0.210 vs
0.215 in
the single female
paratype
; (2) fewer infralabials 9/10 vs 10; (3) fewer anterior temporals 1 vs 2; however,
Janssen
et al.
(2019)
already documented the condition “2*” each for one side of both
paratypes
, meaning two anterior temporals with the lowermost not touching the postocular, thus referred to as posterior temporal herein, resulting in only one anterior temporal in afore mentioned cases in the type series already.
The Vietnamese specimen (VNMN011227) generally agrees with the morphological data of the original description of
Lycodon pictus
, except for having (1) a slightly longer tail, TaL/TL 0.219 vs
0.211 to 0.215 in
the single juvenile and the single female from the
type
series for which TaL/TL ratio was available, (2) slightly fewer maxillary teeth (12 vs 13 or 14) and (3) fewer subcaudals 85 vs 90 or 91.
Both specimens showed more bands on the tail; 14 dark bands in CIB 115609 and 15 dark bands in VNMN011227 (vs 9 and 13); 14 light bands in CIB 115609 and 16 light bands in VNMN011227 (vs 9+ and 13).
Extended diagnosis:
Lycodon pictus
can be differentiated from its congeners by the following morphological characters: dorsal scales in 17–17–15 rows, all smooth; supralabials eight (rarely nine); infralabials ten (rarely nine); one elongated loreal on each side, either in contact with the eye or separated from it; precloacal plate single; ventral scales 212-218 (plus one or two preventral scales); subcaudals 85-91; a total length of 597+ mm in males and
543-591 mm
in females; tail / total length ratio
0.210
-0.219
in
females; maxillary teeth 12 to 14; dorsal surface of body with 28 or 29 light body bands; dorsal surface of tail with 9 to 15 dark bands, and 13 to 16 cream bands forming a distinct blotch in the vertebral region; ventral surface of body and tail mostly cream with the dark body bands in part extending towards the venter, sometimes forming complete dark bands around the body.
Fig. 4. Map showing the new findings of
Lycodon pictus
. 1: VNMN 011227, from closeby the type locality in Cao Bang Province, northern Vietnam. 2: CIB 115609, the new country record of
L. pictus
from Nanggong, Guangxi, southern China.
Distribution:
Lycodon pictus
is currently known from the
type
locality in
Cao Bang Province
, northern
Vietnam
and Longzhou County in
Guangxi
, southern
China
(
Fig. 4
).
Etymology:
The specific name of the species, “
pictus
”, meaning painted or decorated in Latin, refers to the unique dorsal color pattern of this species (
Janssen
et al.
, 2019
). Because this species is herein reported as a new member of the Chinese snake fauna, we suggest “Jin Bai Huan She (DZ白ẇffi)” as its Chinese common name, deriving from its scientific name.
Natural history:
Lycodon pictus
inhabits karst environment in between elevations of
233 m
(
Nonggang
,
Guangxi
,
China
, this study,
Fig. 5
) and
701 m
a.s.l. (
type
locality;
Janssen
et al.,
2019
). In southern
China
, the species was found at night between 00:00 and 1:00 am after light rain, active in a drainage ditch along a forest path, covered with dead leaves. The surrounding habitat was secondary karst forest, consisting of short hardwood, shrubs and vines. The snake did not attempt to bite when it was handled, neither aggressive nor defensive behavior was observed. In terms of the herpetofauna, several other amphibians and reptiles were observed during the survey period in
2019 in
the same microhabitat, including
Kurixalus odontotarsus
(Ye & Fei in
Ye
et al.
, 1993
),
Rhacophorus kio
(
Ohler & Delorme, 2006
)
,
Draco maculatus
(
Gray, 1845
)
,
Acanthosaura lepidogaster
(
Cuvier, 1829
)
,
Goniurosaurus luii
Grismer, Viets & Boyle, 1999
, and
Psammodynastes pulverulentus
(
Boie, 1827
)
.