A new species of the genus Paramesotriton (Caudata: Salamandridae) from Guangxi Zhuang Autonomous Region, southern China
Author
Wu, Yunke
Author
Rovito, Sean M.
Author
Papenfuss, Theodore J.
Author
Hanken, James
text
Zootaxa
2009
2060
59
68
journal article
10.5281/zenodo.186817
68a53ec2-9247-485e-b075-a1ac6baaf487
1175-5326
186817
EE45E241-F388-4FA3-9A2E-345E6983DD64
Paramesotriton ermizhaoi
species nov.
(
Fig. 3
ABC)
Holotype
:
CIB
88141, an adult male collected in Mt. Dayao (
24°07´N
,
110°13´E
,
881m
elevation), Jinxiu Yao Autonomous County, Guangxi Zhuang Autonomous Region, P. R.
China
; collected by Jiatang Li on
July 7, 2006
.
Paratypes
: Same locality as
holotype
:
CIB
88140,
CIB
95998-96000, collected with the
holotype
on the same date;
MVZ
230616
-
230621
, collected by E. Zhao in
March 1999
.
FIGURE 3.
A: Dorsal view of living
P. ermizhaoi
(CIB 95998, paratype: Ƥ); B: Ventral view of living
P. ermizhaoi
(CIB 88141, holotype: 3). C: habitat of
P
.
ermizhaoi
in Mt. Dayao, Jinxiu Yao Autonomous County, Guangxi Zhuang Autonomous Region, China.
Diagnosis
:
Paramesotriton ermizhaoi
is assigned to the genus
Paramesotriton
because of its slender and nearly straight epibranchial bones, maxillary bones oriented angular to the body axis, and laterally compressed tail. This species can be diagnosed from other congeners by the following combination of characters: skin relatively smooth; granular warts absent on head and body; vertebral ridge not prominent; head depressed and nearly flat in profile; habitus slender and depressed; limbs short—when adpressed against flank, fingers and toes hardly meet; dorsum olive brown with irregular black flecks; ventral orange-red blotches irregular in shape.
Description of the
holotype
: A slender and flat newt, preserved with mouth open. Head oval in shape, depressed and nearly flat in profile. Snout truncate and slightly projecting beyond lower mandible. Nostrils close to snout tip. Labial fold evident throughout posterior half of upper jaw. Skull relatively narrow, with maxillary bones oriented angular to body axis. Maxillary tips lie anterior and lateral to pterygoid bones; no contact between maxillary and pterygoid. Fronto-squamosal arch complete but not very robust. Epibranchial bones slender, nearly straight, only slightly flared dorsally. Vomerine tooth patch Λ-shaped, tooth rows converging anteriorly and exceeding the anterior limit of choanae. Tongue adhering to mouth floor with free lateral margins. Parotoid region evident, but not enlarged. Gill filaments absent. Gular fold present. Skin relatively smooth on head and body, with small transverse wrinkles. Vertebral ridge thin, slightly elevated. Lateral dorsal ridge absent. Thirteen trunk vertebrae. Four fingers, five toes, without webbing. Tail laterally compressed; posterior dorsal caudal fin evident, ventral caudal fin indistinct; tail extremity round in profile. Cloaca swollen, with a few papillae near posterior limit.
Color of
holotype
in life
: Dorsum olive brown with irregular black flecks. Vertebral ridge with orange tint. Venter paler brown. Irregular orange-red blotches on venter and anterior portion of cloaca with indistinct black margin; some blotches connected into short irregular stripes. Orange-red on underside of tail.
In preservative, dorsum and venter black. Vertebral ridge inconspicuous. Ventral bright orange fading to yellow to milky white; black margins invisible.
Variation
: Morphology of
paratypes
resembles that of
holotype
except that females have smaller and nonswollen cloaca without papillae. Linear measurements are summarized in
Table 2
. Color of ventral blotches ranges from orange to red, spreading to chin and underside of axillae, varying in shape and arrangement. Black marks border those blotches or intersperse on venter.
TABLE 2.
Linear measurements of
Paramesotriton ermizhaoi
. See text for abbreviations. Holotype is included in the measurements of males. Unit: mm.
Holotype
Females (N = 6) Males (N = 5)
Measurements (CIB 88141) Range Mean ± SE Range Mean ± SE SVL 63.5 46.6–66.8 56.3 ± 2.7 46.4–63.5 56.1 ± 3.1 TTL 126.0 94.0–137.5 112.8 ± 5.9 92.2–127.6 111.5 ± 6.8 TAL 57.7 44.7–65.5 53.4 ± 3.0 43.3–60.2 51.1 ± 3.3 TAD 7.5 5.5–8.1 7.0 ± 0.4 5.5–8.5 7.3 ± 0.5 HL 17.7 14.4–17.4 15.9 ± 0.5 14.8–17.8 16.1 ± 0.7 HW 12.1 8.8–12.6 10.7 ± 0.5 9.1–12.3 10.9 ± 0.6 IO 7.1 5.3–6.9 6.0 ± 0.2 5.4–7.1 6.4 ± 0.3 EN 4.9 3.2–4.2 3.8 ± 0.2 3.1–4.9 4.0 ± 0.3 IN 3.7 2.7–3.6 3.1 ± 0.1 2.4–3.7 3.1 ± 0.2 AX 31.3 20.2–36.7 27.7 ± 2.2 21.4–31.3 27.6 ± 1.7 AL 15.6 12.6–15.4 13.8 ± 0.4 12.5–17.4 14.6 ± 0.9 PL 16.0 13.1–15.6 14.2 ± 0.4 13.5–17.4 15.2 ± 0.7
Etymology
: The new species is named after Ermi Zhao, a prominent Chinese herpetologist and educator, for his great contribution to the development of herpetological study and the training of a new generation of scientists in
China
.
Habitat
: Stream in broadleaf forest with herbaceous plants and vines. Stream is 3-4 meters wide and shallow, flowing slowly in a valley (
Fig. 3
C). Substrates include gravels, scattered small rocks, and semisubmerged larger rocks. Along the stream are pools with a very slow current. Newts are found at the stream bottom, usually under rocks or between crevices during daytime. Fishes and small aquatic invertebrates coexist with
Paramesotriton ermizhaoi
, and
Pachytriton labiatus
is found in the same stream drainage at a higher elevation.
FIGURE 4.
Radiograph of
P. ermizhaoi
(CIB 88141, holotype: 3). Arrow points to the 13th trunk vertebrae.
Discussion
:
Paramesotriton ermizhaoi
is unusual insofar as a large portion of individuals possess 13 trunk vertebrae; other congeneric species normally have 12 trunk vertebrae (
Chan
et al.
2001
). Although variation has been observed in other
Paramesotriton
, it is rare. However, six of eleven
P. ermizhaoi
(including the
holotype
) have 13 trunk vertebrae (
Fig. 4
); the other five specimens have 12. The number of trunk vertebrae does not appear to be correlated with gender. A similar situation occurs in the European salamandrid
Ommatotriton ophryticus
, in which the modal number of trunk vertebrae varies from
12 to 13 in
different geographic populations (
Litvinchuk
et al.
2005
).
Orska and Imiolek (1962)
reported the correspondence of vertebral number to developmental temperature in salamanders. Future research is necessary to evaluate the correlation between environmental temperature and embryonic development in
P. ermizhaoi
.
Paramesotriton ermizhaoi
may have been long misidentified as another Asian salamandrid species.
Scholz (1998)
reported a potentially new species of
Pachytriton
from the pet trade, named
Pachytriton
C. In
fact, most descriptions of morphology, coloration, and behavior of
Pachytriton
C match with
P. e r m i z h a o i
. Due to lack of molecular data and known locality,
Scholz (1998)
did not make a definitive taxonomic statement on
Pachytriton
C. We
suspect that the two names refer to the same species.
The only known locality of
P. ermizhaoi
, Mt. Dayao
, is located within the putative Guangxi population of
P. c h i n e n s i s
(
Fei
et al.
1999
;
Zhang & Wen 2000
;
Fei
et al.
2006
), which was first described in rivers at inland from Ningbo, Zhejiang Province (
Gray 1859
). However,
P. ermizhaoi
has been identified mistakenly as
P. chinensis
despite their different morphologies. For instance, the
paratypes
of
P. e r m i z h a o i
from MVZ were originally catalogued as
P. c h i n e n s i s
. We also note that the
P. chinensis
used by
Lu
et al.
(2004)
from Mt. Dayao actually are
P. ermizhaoi
, based on mitochondrial sequences. To our knowledge, no true
P. c h i n e n s i s
has been collected from Mt. Dayao. It is possible that claims of a disjunct Guangxi population of
P. chinensis
are incorrect due to misidentification. However,
Zhang and Wen (2000)
provide an account on Guangxi
P. chinensis
that matches the diagnostic characters of this species. More fieldwork is needed to determine if
P. chinensis
occurs in Guangxi Zhuang Autonomous Region.
Comparative material examined
:
P. caudopunctatus
(
MVZ
236250-236254 from Guizhou,
China
),
P. chinensis
(
MVZ
230360
,
CIB
95899,
CIB
95907-95911 from Zhejiang,
China
),
P. fuzhongensis
(
MVZ
230622
-
230625
from Guangxi Zhuang Autonomous Region,
China
),
P. hongkongensis
(
MVZ
230365
-
230370
from
Hong Kong
,
China
),
P. deloustali
(
MVZ
222122-222123,
MVZ
223627-223629 from Tam
Dao
,
Vietnam
),
P. laoensis
(
FMNH
255450,
FMNH
257850,
FMNH
257852,
FMNH
257853 from Xiang Khouang,
Laos
).