A new species of reed snake, Calamaria (Squamata: Colubridae), from the Central Truong Son (Annamite mountain range), Vietnam
Author
Ziegler, Thomas
Author
Quyet, Le Khac
text
Zootaxa
2005
1042
27
38
journal article
50963
10.5281/zenodo.169839
6e63434b-16a3-4599-a191-7f66b91d5d21
11755326
169839
122F30DC-4653-439D-898C-12F383435321
Calamaria thanhi
sp. n.
Figures 1–6
.
Holotype
.—
An adult female (
ZFMK
82920), adjacent to Phong Nha
Ke Bang National Park, Dan Hoa Commune, Minh Hoa District, Quang Binh Province,
Vietnam
, collected on
16 June 2003
by local people in a limestone cave of primary forest; for injuries prior to collection see
Figures 1–6
.
Diagnosis.—
Calamaria thanhi
sp. n.
can be distinguished from all congeners on the basis of the following combination of characters: 1) rostral wider than high, portion visible from above longer than prefrontal suture; prefrontal shorter than frontal, touching first two supralabials; 2) single nasal; 3) frontal hexagonal, more than 2.5 times maximum width of supraocular, and about twothirds length of parietal; 4) paraparietal surrounded by six shields and scales; 5) eye diameter larger than eyemouth distance; 6) preocular absent; 7) absent loreals and anterior temporals; 8) four supralabials, second and third entering orbit; fourth supralabial longest and in broad contact with parietal, third ¾ of second, first slightly shorter than third; 9) modified maxillary teeth; 10) five infralabials, three touching anterior chin shield; 11) mental not touching anterior chin shields; only first pair of chin shields meeting in midline; 12) three gular scales in midline between posterior chin shields and first ventral; 13) 198 ventrals; 21 divided subcaudal scales; 14) single anal plate; 15) smooth dorsals; dorsal scale row reduction on tail to five opposite last subcaudal anterior to terminal scute; 16) large size (total length up to
455 mm
); tail moderately long, tapering gradually to a point; 17) dark bluish greyish dorsum, iridescent; anterior body with four pale zigzag bands; yellowish markings on dorsum of tail base and tail tip; 18) ventral side of body immaculate beige yellowish; underside of head greyish brownish; beige yellowish tail base with small dark flecks and dark outermost corners of subcaudals.
Description of
holotype
.—
Rostral wider (
2.6 mm
) than high (
1.8 mm
), portion visible from above longer (
1.7 mm
) than prefrontal suture (
1.3 mm
). Prefrontal shorter (
2.7 mm
) than frontal (
3.2 mm
), touching first two supralabials. Frontal hexagonal, more than 2.5 times (
2.6 mm
) maximum width of supraocular (1.0 mm), length about twothirds that of the parietal (
4.7 mm
). Parietal about 1.7 times length of prefrontal. Paraparietal surrounded by six shields and scales. Nasal smaller than postocular. No preocular. Postocular higher than wide, not as high (
0.9 mm
) as eye diameter (
1.4 mm
). Eye diameter larger than eyemouth distance (1.0 mm). Distance from anterior corner of eye to centre of nostril
2.4 mm
, and from anterior corner of eye to tip of snout
3.8 mm
. Four supralabials, second and third entering orbit, fourth longest, third ¾ of second, first slightly shorter than third and about half as long as second. Mental semicircular to triangular, not touching anterior chin shields. Five infralabials, three touching anterior chin shield. First pair of chin shields meeting in midline, second pair diverging and only touching anterior. Three gulars in midline between posterior chin shields and first ventral. 198 ventral scales, and 21 divided subcaudals. A single anal scale. Thirteen smooth scales across the midbody.
The number of dorsal scale rows is reduced to six rows on tail opposite 8th subcaudal posterior to cloaca (reduction to five rows only opposite last subcaudal anterior to terminal scute).
Snoutvent length
424 mm
, tail length
31 mm
. Body thickness about
7 to 8 mm
, tail root
5.5 mm
thick. Tail moderately long, relatively thin, tapering gradually to a point. Ratio of tail to total length (
455 mm
) is 0.068. Vermiform habitus, head indistinct from neck. Modified (most probably nine) maxillary teeth.
Colour preserved in ethanol dark bluish to greyish above, iridescent. Parietals and subsequent scales with indistinct light beige to yellowish markings. Lower parts of supralabials yellowish, most distinct below and somewhat behind the eyes. Dorsal scales posterior in part with more or less light markings, especially on the sides of the anterior body half. Outermost dorsal scale rows light yellowish beige below. Four beige to yellowish dorsal bands are well discernible in the anterior body half: each band is half a scale to two scales broad, somewhat zigzag shaped and turns into the yellowish beige coloration of the venter. The first yellowish dorsal band is located about
1 cm
behind the head, the others follow each with distances of about
3.5 cm
. Small yellowish markings can be found on the dorsum of the tail base as well as on the dorsal tail tip: whereas the anterior light dorsal area, situated about half a centimetre behind the anal scale, is recognizable as rudiment of a thin zigzag shaped band, comprising five scale rows, the yellow fleck on the tail’s end covers only the hind part of a single scale bordering the tail tip. The ventral side of the body is immaculate yellowish to beige. Similar to the body venter the tail base is yellowish beige except for some small dark flecks and the dark outermost corners of the subcaudals. The underside of the head appears greyish to brownish.
Etymology.—
We dedicate this new species to our friend and colleague Vu Ngoc Thanh (
Vietnam
National University, Hanoi, University of Science, Faculty of Biology, Department of Vertebrate Zoology, Zoological Museum) in recognition of his valuable support during numerous biodiversity excursions in
Vietnam
.
As
common names we suggest Thanh’s reed snake (English), Ran mai gam Thanh (Vietnamese), Calamaire de Thanh (French), and Thanhs Zwergschlange (
German
).
Comparisons.—
Calamaria thanhi
sp. n.
differs according to
Inger & Marx (1965)
and
Darevsky & Orlov (1992)
from the Vietnamese species as follows:
C. buchi
is blackish above, each dorsal scale with small light spots; in addition,
C. buchi
has a higher count of ventral scales (221–236 vs.
198 in
C. thanhi
sp. n.
), fewer subcaudal scales (13–14 vs. 21), preocular present, rostral higher than wide (vs. rostral wider than high), its mental touching the anterior chin shields (which is not the case in
C. thanhi
sp. n.
), only five (vs. six) scales touch the paraparietal, dorsal scale reduction to four rows on tail opposite the third to fourth subcaudal anterior to terminal scute, and a ratio of tail to total length of 0.039 to 0.041 (vs. 0.068) in females.
FIGURE 1.
Dorsal view of the ethanolpreserved holotype of
Calamaria thanhi
sp. n.
(ZFMK 82920).
FIGURE 2.
Ventral view of the ethanolpreserved holotype of
Calamaria thanhi
sp. n.
(ZFMK 82920).
FIGURE 3.
Oblique view of the head and neck region of the ethanolpreserved holotype of
Calamaria thanhi
sp. n.
(ZFMK 82920).
FIGURE 4.
Lateral view of the head of the ethanolpreserved holotype of
Calamaria thanhi
sp. n.
(ZFMK 82920).
FIGURE 5.
Ventral view of the head of the ethanolpreserved holotype of
Calamaria thanhi
sp. n.
(ZFMK 82920).
FIGURE 6.
Dorsal view of the tail of the ethanolpreserved holotype of
Calamaria thanhi
sp. n.
(ZFMK 82920). Photos by Thomas Ziegler.
C. pavimentata
usually has narrow, dark, longitudinal stripes, a solid black collar immediately behind the neck, ventrals with dark lateral tips, a slightly smaller first supralabial than the second (vs. a first supralabial that is about half as long as second in
C. thanhi
sp. n.
), the second pair of chin shields meeting in midline (which is not the case in
C. thanhi
sp. n.
, where the second pair diverges and only touches anteriorly), a rostral that is as broad as high (or slightly higher vs. a rostral that is wider than high), dorsal scale row reduction usually to four (vs. five) on tail, a rostral portion visible from above only onehalf to equal entire length of prefrontal suture (vs. a rostral portion visible from above longer than prefrontal suture in
C. thanhi
sp. n.
), and a preocular present.
C. septentrionalis
has dorsal scales with many small light dots forming a network, lower counts of ventral and subcaudal scales in females (168–188 vs. 198 and 6–11 vs. 21), rostral portion visible from above less than onethird length of prefrontal suture (vs. a rostral portion visible from above longer than prefrontal suture in
C. thanhi
sp. n.
), preocular present, the tail being as thick as body, not tapering, with a broadly rounded tip (vs. a relatively thin tail in
C. thanhi
sp. n.
that is tapering gradually to a point), and a ratio of tail to total length of 0.026 to 0.043 (vs. 0.068) in females.
C. lovii ingermarxorum
has an immaculate greybluish dorsum with light spots on each side of the neck covering four scales, uniformly dark grey ventrals with light posterior edges, prefrontals being longer than frontal (vs. prefrontals shorter than frontal in
C. thanhi
sp. n.
), rostral portion visible from above more than half length of prefrontal suture (vs. a rostral portion visible from above longer than prefrontal suture), its mental touching the anterior chin shields, dorsal scale reduction to four rows on tail opposite first to fifth subcaudal anterior to terminal scute, and a short, blunt tail that is not tapering (vs. a relatively thin tail that is tapering gradually to a point).
Our new
Calamaria
species can be distinguished from the other subspecies of
C. lovii
, that do not occur in
Vietnam
, according to
Inger & Marx (1965)
e.g. by its quite large total length (
455 mm
vs.
316 mm
in
C. l.
lovii
Boulenger,
315 mm
in
C. l. wermuthi
Inger & Marx, and
269 mm
in
C. l.
gimletti
Boulenger), the ventral and subcaudal counts (198 and 21 vs. 218–254 and
11–18 in
C. l.
lovii
, 256 and
11 in
C. l. wermuthi
, and 215–249 and
10– 12 in
C. l.
gimletti
), by its eye diameter being larger than the eyemouth distance and by a differing coloration and pattern; in addition, contrary to the situation in
C. thanhi
sp. n.
, in
C. l.
lovii
and
C. l. wermuthi
the mental touches the anterior chin shields and in
C. l.
gimletti
the rostral portion visible from above is distinctly smaller than the prefrontal suture (vs. a rostral portion visible from above being longer than prefrontal suture in
C. thanhi
sp. n.
).
Calamaria thanhi
sp. n.
differs from the Chinese species
C. yunnanensis
Chernov
, that was judged as doubtful form by
Inger & Marx (1965)
, but listed as valid by
Yang & Inger (1986)
or
Zhao & Adler (1993)
, in lacking narrow, dark, elongated stripes along the body, dark edges on the ventrals, and in having a higher ventral count (198 vs. 173) as well as in a lower tail ratio (0.068 vs. 0.082).
From the four
Calamaria
species, that reach Malay Peninsula (
C. albiventer
Gray
,
C. ingeri
Grismer, Kaiser & Yaakob
,
C. schlegeli
Duméril & Bibron
) and
Thailand
(
C. lumbricoidea
Boie
) in the north,
C. thanhi
sp. n.
is distinguishable in lacking five supralabials, of which the third and fourth entering the orbit (namely four supralabials with second and third entering orbit in
C. thanhi
sp. n.
), and in lacking a preocular (present in
C. albiventer
,
C. ingeri
and
C. lumbricoidea
), in lacking a mental that touches the anterior chin shields (as is present in
C. albiventer
and
C. lumbricoidea
), in having a higher ventral count in females (198 vs.
136180 in
C. schlegeli
and vs.
147162 in
C. albiventer
), by having a paraparietal that is surrounded by six and not only by four or five scales or shields as in
C. lumbricoidea
, as well as in pattern (
C. albiventer
: body with four narrow light stripes,
C. lumbricoidea
: belly with black crossbars,
C. schlegeli
: distinctly bicolored).
Most of the remaining, geographically quite distant
Calamaria
species from Sumatra, Borneo, Java, the
Philippines
, Sulawesi and the
Moluccas
can be distinguished from
C. thanhi
sp. n.
not only by coloration and pattern but also by the presence of the (due to its limited intraspecific variation) stable character of five supralabials (four in
C. thanhi
sp. n.
), of which, in addition, the third and fourth (and not the second and third as in
C. thanhi
sp. n.
) enter the orbit (
C. abstrusa
Inger & Marx
,
C. acutirostris
Boulenger
,
C. alidae
Boulenger
,
C. apraeocularis
Smith
,
C. bicolor
Duméril & Bibron
,
C. bitorques
Peters
,
C. boesemani
Inger & Marx
,
C. brongersmai
Inger & Marx
,
C. ceramensis
de Rooij,
C. crassa
Lidth
de Jeude,
C. curta
Boulenger
,
C. doederleini
Gough
,
C. eiselti
Inger & Marx
,
C. everetti
Boulenger
,
C. forcarti
Inger & Marx
,
C. gervaisi
Duméril & Bibron
,
C. grabowskyi
Fischer
,
C. griswoldi
Loveridge
,
C. hilleniusi
Inger & Marx
,
C. joloensis
Taylor
,
C. lateralis
Mocquard
,
C. lautensis
de Rooij,
C. leucogaster
Bleeker
,
C. lumholtzi
Andersson
,
C. margaritophora
Bleeker
,
C. mecheli
Schenkel
,
C. modesta
Duméril & Bibron
,
C. muelleri
Boulenger
,
C. nuchalis
Boulenger
,
C. palavanensis
Inger & Marx
,
C. prakkei
Lidth
de Jeude,
C. rebentischi
Bleeker
,
C. suluensis
Taylor
,
C. sumatrana
Edeling
,
C. ulmeri
Sackett
, and
C. virgulata
Boie
). Of the remaining species,
C. battersbyi
Inger & Marx
,
C. borneensis
Bleeker
,
C. linnaei
Boie
, and
C. melanota
Jan
possess a preocular,
C. schmidti
Marx & Inger
bears unmodified maxillary teeth,
C. gracillima
(Günther)
has the supraocular fused with the postocular, and
C. javanica
Boulenger
has, besides distinctly lower subcaudal counts in females (10–12 vs. 21), four gulars (vs. three gulars in
C. thanhi
sp. n.
) in midline between posterior chin shields and first ventral, which clearly distinguish all of them from
C. thanhi
sp. n.
Distribution and Natural History.—
Calamaria thanhi
sp. n.
is only known from the
type
locality. Records for
Laos
are to be expected in the future, due to the close proximity of the
type
locality to the Laotian border.
The snake was found heavily injured on the ground of a large limestone cave under a mist net. Further records of that species must confirm, whether
C. thanhi
sp. n.
is adapted to primary limestone forest caves. The adult female, which was collected during the dry season, contained at least seven large eggs besides smaller ova in the ovaries; folded oviducts indicated, that eggs had already been laid. Concerning the larger eggs, mean egg length measured
10.7 +/ 1.5 mm
(min. 8.0, max.
12.2 mm
), mean egg width was
3.4 +/ 0.9 mm
(min. 2.3, max.
4.5 mm
).