A new arboreal Pseudoeurycea (Caudata: Plethodontidae) from the Sierra de Zongolica, Veracruz, Mexico
Author
Cazares-Hernandez, Erasmo
https://orcid.org/0000-0002-9160-5683
Instituto Tecnologico Superior de Zongolica, Coleccion Cientifica del ITSZ y Herbario ZON. Km 4 Carretera a la Compania S / N, Tepetitlanapa CP 95005, Zongolica, Veracruz, Mexico
Author
Jimeno-Sevilla, H. David
Instituto Tecnologico Superior de Zongolica, Coleccion Cientifica del ITSZ y Herbario ZON. Km 4 Carretera a la Compania S / N, Tepetitlanapa CP 95005, Zongolica, Veracruz, Mexico
Author
Rovito, Sean M.
https://orcid.org/0000-0002-4713-9654
Unidad de Genomica Avanzada (LANGEBIO), CINVESTAV, Irapuato, Guanajuato, Mexico
Author
Lopez-Luna, Marco Antonio
Division Academica de Ciencias Biologicas, Universidad Juarez Autonoma de Tabasco, Carretera Villahermosa-Cardenas km 0.5 Villahermosa, Tabasco CP 86039, Mexico
Author
Canseco-Marquez, Luis
https://orcid.org/0000-0001-9218-4756
Laboratorio de Herpetologia, Facultad de Ciencias, Universidad Nacional Autonoma de Mexico, Distrito Federal 04510, Mexico
lcanseco@gmail.com
text
Vertebrate Zoology
2022
2022-10-20
72
937
950
http://dx.doi.org/10.3897/vz.72.e87275
journal article
http://dx.doi.org/10.3897/vz.72.e87275
2625-8498-72-937
E47F65F692D24C02AD2B0C4B0881C519
472A867134905BCE9432DCE2C52D2CA1
Pseudoeurycea jaguar
sp. nov.
Figs 1
, 2
, 3
, 4
Chresonymy.
Pseudoeurycea
sp. -
Cazares-Hernandez
et al. 2021
.
Suggested English name: Jaguar Salamander.
Suggested Spanish name: Tlaconete jaguar.
Holotype.
MZFC-HE 28694. An adult male from El Mirador, Texhuacan Municipality, Veracruz, Mexico (
18°38′04.8″N
,
97°03′35.0″W
, 2,367 m elevation, WGS84 datum), collected by Erasmo
Cazares
Hernandez
on 5 September 2015.
Paratypes.
Seven. One male: MZFC-HE 35855 (10 September 2015); six females: MZFC-HE 35859 (10 September 2015), MZFC-HE 28686 (11 September 2015), MZFC-HE 35856-57 (14 September 2015), MZFC-HE 35858, 28685 (10 October 2015). Same locality as the holotype.
Diagnosis.
Assigned to the genus
Pseudoeurycea
based on the presence of a sublingual fold, comparatively short fifth toe compared to the fourth, limited foot webbing, relatively large size, and mitochondrial DNA sequences.
Morphologically, we distinguish the new species from the other salamanders that occur in the region and from the others of the genus
Pseudoeurycea
based on size of the body and tail, limb length, digit shape, shape and size of the head, and especially by external coloration (dorsal and ventral coloration of head, body and tail).
Pseudoeurycea jaguar
is easily distinguished from the other species of the genus
Pseudoeurycea
by its unique color pattern (Figs
1
,
4
).
Based on mtDNA, this new species is closely related to members of the
P. juarezi
group (
sensu
Canseco-Marquez
and Parra-Olea 2003
;
Parra-Olea et al. 2004
). It is distinguished from species of the
P. juarezi
group by its larger body size (SVL males:
P. aurantia
SVL 40.2-45.0,
P. jaguar
sp. nov.
58.0-58.7 mm,
P. juarezi
44.0-51.3 mm,
P. ruficauda
24.2 mm,
P. saltator
40.0-42.3 mm; females:
P. aurantia
41.5-44.1 mm,
P. jaguar
sp. nov.
42.4-71.0 mm,
P. juarezi
38.5-48.0 mm,
P. ruficauda
38.2 mm,
P. saltator
33.4-41.2 mm; Tables
1
and
2
) and wider head (HW males:
P. aurantia
9.9-11.2 mm,
P. jaguar
sp. nov.
13.7-15.1 mm,
P. juarezi
10.0-12.6 mm,
P. ruficauda
6.7 mm,
P. saltator
9.5-10.3 mm; females:
P. aurantia
10.3-10.7 mm,
P. jaguar
sp. nov.
11.0-17.6 mm,
P. juarezi
9.4-12.5 mm,
P. ruficauda
8.5 mm,
P. saltator
3.8-9.1 mm. Females have a relatively longer tail (TL/SVL females:
P. aurantia
0.86-0.90,
P. jaguar
sp. nov.
0.93-1.25,
P. juarezi
0.70-1.12,
P. ruficauda
0.99,
P. saltator
0.88-0.92).
Pseudoeurycea jaguar
sp. nov.
has more maxillary and premaxillary teeth (mean MT + PMT males:
P. aurantia
69,
P. jaguar
sp. nov.
85.5,
P. juarezi
73,
P. ruficauda
31,
P. saltator
67; females;
P. aurantia
74,
P. jaguar
sp. nov.
92.6,
P. juarezi
67,
P. saltator
73) and vomerine teeth (mean VT males:
P. aurantia
25,
P. jaguar
sp. nov.
30.5,
P. juarezi
23.3,
P. ruficauda
17,
P. saltator
26; females;
P. aurantia
22,
P. jaguar
sp. nov.
30.3,
P. juarezi
22,
P. saltator
22). The head of
P. jaguar
is longer and wider than that of other species (HL males:
P. aurantia
9.9-11.2,
P. jaguar
sp. nov.
13.7-15.1 mm,
P. juarezi
10.0-12.6 mm,
P. ruficauda
6.7 mm,
P. saltator
9.5-10.3 mm; females:
P. aurantia
10.3-10.7 mm,
P. jaguar
sp. nov.
11.0-17.6 mm,
P. juarezi
9.4-12.5 mm,
P. ruficauda
8.5 mm,
P. saltator
3.8-9.1 mm; HW males:
P. aurantia
6.3-6.8,
P. jaguar
sp. nov.
9.8-10.3 mm,
P. juarezi
6.2-7.9 mm,
P. ruficauda
4.4 mm,
P. saltator
6.3-6.7 mm; females:
P. aurantia
6.1-6.7 mm,
P. jaguar
sp. nov.
7.8-12.0 mm,
P. juarezi
5.9-7.8 mm,
P. ruficauda
6.1 mm,
P. saltator
5.4-6.7 mm). No other species of
Pseudoeurycea
from Veracruz or Puebla has such large, extensively webbed feet and long limbs.
The new species is further distinguished from all members of the
Pseudoeurycea juarezi
group, as well as from all other species of
Pseudoeurycea
and all salamander species from central Veracruz, by color pattern.
Pseudoeurycea jaguar
has irregular yellow mottling on the dorsum on a brown or nearly black background. In
P. aurantia
the ground color is reddish brown with bright orange blotches or mottling present on the dorsum; these blotches coalesce on the tail (Fig.
1A
), and some individuals have small dark spots on the tail and dorsum.
Pseudoeurycea saltator
has a uniformly dark gray-brown dorsal ground color that is invariably overlain by a paler yellow or golden mid-dorsal stripe (Fig.
1B
).
Pseudoeurycea juarezi
typically has yellow-brown dorsal coloration on the head and forming a dorsal band to the tip of the tail, with scattered black spots on the dorsum and tail (Fig.
1C
); the color pattern in this species can be variable, some specimens have small dark spots on a yellowish background (Fig.
1D
) while others are darker brown or reddish-brown dorsally with yellow or golden mottling on the tail. Dorsal coloration in
P. ruficauda
is orange-tan with coppery-gold highlights that are mixed with black (Fig.
1E
). The ventral part of the tail of
P. jaguar
is paler than the dorsal part (lead gray), darkening towards the tip, with very small and clear flecks evenly distributed along the median portion of the venter. Both
P. melanomolga
and
P. gadovii
have some version of yellowish spots on a dark background, but the spots in these species are arranged in regular rows unlike the mottling seen in
P. jaguar
.
Pseudoeurycea lynchi
has greenish, rather than yellow, blotches and mottling and tends to show less background color compared to
P. jaguar
.
Pseudoeurycea nigromaculata
also typically shows less background color and often is primarily yellowish on the tail, and
P. granitum
has irregular blotches and a pale interorbital bar that are lacking in
P. jaguar
.
Figure 1.
Live specimens of all members of the
P. juarezi
group.
A
P. aurantia
(
Pena
Verde, Oaxaca), Photo by Sean Rovito;
B
P. saltator
(Sierra de
Juarez
, Oaxaca), Photo by Sean Rovito;
C
,
D
P. juarezi
(Cerro
Pelon
, Sierra de
Juarez
, Oaxaca), Photos by Sean Rovito and Luis Canseco, respectively;
E
P. ruficauda
(near Plan de Guadalupe, Oaxaca), Photo by Sean Rovito;
F
Holotype of
P. jaguar
sp. nov.
from the type locality, Photo by Erasmo
Cazares
.
Description of the holotype.
A relatively large adult male (58.7 SVL), body slender, head relatively long and broad (HW/SVL = 0.17), wider than body, neck region well defined (Fig.
2A, B
). Snout slightly truncate in dorsal view and rounded in lateral view, eyes moderate in size, slightly protruding, not exceeding margin of jaw in dorsal view. Nostrils small, oval. Nearly round and relatively prominent mental gland (2.4 mm wide) (Fig.
2B
). Costal folds 13, counting one each in axilla and groin. Tail longer than body (TL/SVL = 1.15), tapering gradually along length, slender posteriorly ending in a point. Limbs long, overlap by 2 costal folds when appressed to side of body (Fig.
3D
). Hands and feet broad, digits long and relatively slender, blunt with distinct subterminal pads. Hands and feet highly webbed compared to most other members of the genus (although only moderately webbed compared with species of
Bolitoglossa
or some
Chiropterotriton
), with webbing extending to the middle of the penultimate phalanx on third toe of foot. First toe short, fifth toe short compared to fourth long, 2.1 times larger than the first finger. Digits in order of decreasing length: III-II-IV-I on hands; III-IV-II-V-I on feet. Phalangeal formulae 1-2-3-2 for hands and 1-2-3-3-2 for feet (Fig.
2C, D
). Teeth numerous: maxillary teeth 92 (45/47); premaxillary teeth 3, enlarged compared to maxillary teeth; vomerine teeth 36, arranged in two arcs (18/18) extending beyond the choanae. Nasolabial protuberances well developed.
Figure 2.
A
Dorsal and
B
ventral view of the holotype of
Pseudoeurycea jaguar
sp. nov (MZFC-HE 28694), scale bar = 10 mm.
C
Ventral view of right hand and
D
right foot. Scale bar = 3 mm.
Figure 3.
A
Ventral view of male paratype of
Pseudoeurycea jaguar
sp. nov.
(MZFC-HE 35855) showing the mental gland.
B
Ventral view of right hand and
C
right foot of a female paratype (MZFC-HE 28685).
D
Male paratype male showing overlapping digits when appressed to the side of the body (MZFC-HE 35855). Scale bar = 2 mm.
Measurements of the holotype (in mm).
Snout to posterior angle of vent (SVL) 58.7; head width 10.3; head length 14.8; head depth at angle of jaw 4.7; eyelid length 3.9; eyelid width 3.0; anterior rim of orbit to snout 4.9; eye diameter 4.4; interorbital distance 3.5; snout to forelimb 21.0; internarial distance 3.1; intercanthal distance 4.1; nostril diameter 0.4; snout projection beyond mandible 1.1; snout to anterior angle of vent 55.4; axilla to groin 29.4; tail length 67.6; tail width at base 4.3; tail depth at base 4.7; forelimb length 18.2; hind limb length 19; hand width 5.1; foot width 8.0; length of the longest (third) toe 2.5; length of fifth toe 0.8; mental gland width 2.4; mental gland length 2.3. Tooth counts: premaxillary 3; maxillary 45/47; vomerine 18/18.
Variation and sexual dimorphism.
The type series includes eight specimens, two males and six females. There is marked sexual dimorphism; adult females reach a larger size than males (SVL 42.4-71.0 mm in females vs. 58.0-58.7 mm in males), head relatively broad (9.8-12.0 mm in females and 9.8-10.3 mm in males) and have a more robust body compared to males (shoulder width 7.6-10.8 in females vs 7.2-7.3 mm in males). Adult males have a well-developed, nearly round mental gland (width 2.8 mm) (Fig.
3A
) and few premaxillary teeth (3-4 vs.13-20 in females). Hands and feet are broader in females (foot width 7.7-8 mm in males and 8.3-9.3 in females) (Fig.
3B, C
).
Coloration of the holotype in life (Fig. 4A).
Dorsum and dorsal surface of head solid dark chocolate brown with extensive yellow speckling or mottling; yellow specks small on head, becoming larger and mottled on the dorsum and even larger and more continuous on tail. Sides of head brown with yellow speckling, with the same proportion of yellow toward back of the head, mouth and dorsal surface of the head. Dorsal surface of tail same color as dorsum, with the yellow mottling more continuous, but reduced at tip. Sides of body dark brown above midline, with yellow flecks (small flecks combined with larger and elongated flecks) and slightly paler brown with limited yellow mottling below midline. Dorsal surface of limbs brown chocolate (same color as dorsal surface of head, body and tail) with yellow specks, which are larger and elongated on the hind limbs; dorsal surface of feet brown with small yellow specks. Ventral surface of body, limbs, gular region and tail pale brown with small yellow flecks. Iris dark brown with yellow specks around the pupil.
Figure 4.
Color pattern of
Pseudoeurycea jaguar
sp. nov.
Adults:
A
Male holotype (MZFC-HE 28694);
B
,
C
,
D
Female paratypes (MZFC-HE 35856-57, 28685, respectively; and released male (
E
) and female (
F
). Juveniles (all released).
G
A specimen <22 mm SVL;
H
a specimen measuring 30 mm SVL;
I
,
J
specimens measuring 33 mm SVL. Photos by Erasmo
Cazares
.
Coloration of the holotype in preservative (Fig. 2A, B).
Dorsum nearly uniformly dark gray, including head and tail, hands, and feet. All irregular spots on body and specks on head cream. Ventral surface of body, limbs and gular region pale gray with numerous cream specks.
Color variation in adult and juvenile specimens (Fig. 4).
The color pattern is similar in most adult specimens. Irregular blotches on the body can vary in size and shape and can be yellow or orange, forming elongated or rounded patterns; they are smaller on the head and become larger along the dorsum and even larger on the tail, but their size varies from specimen to specimen (Fig.
4
). Regardless of the size of the blotches on the dorsum, most specimens have a mottled pattern. There were two adult specimens, one female (MZFC-HE 35857, Fig.
4C
) and one male, that were almost completely dark with small yellow blotches. There appears to be ontogenetic variation in color pattern. In juveniles, the dorsum is almost entirely dark brown or black, without the yellow mottling or blotches as in adults. Some of the smallest specimens (22 mm SVL) are almost totally black, with little or no yellow dorsal coloration (Fig.
4G, H
). Slightly larger juveniles (30-40 mm SVL), show more yellow dorsal coloration (Fig.
4I, J
).
Distribution and natural history.
Pseudoeurycea jaguar
sp. nov.
is known only from Sierra de Zongolica (Fig.
5A
). It is found in a mature coniferous forest (Fig.
5B, C
) at 2,360-2,367 m, which is dominated by
Cupressus benthamii
,
Pinus patula
,
Alnus acuminata
, and
Saurauria leucocarpa
with an understory of
Fuchsia microphyla
,
Rubus
sp.,
Licianthes synanthera
; and herbaceus plants including
Didymaea alsinoides
,
Chusquea mulleri
and
Begonia oaxacana
. There is an abundant presence of epiphytes, including
Tillandsia imperialis
and
Elaphoglossum paleaceum
, with extensive growth of mosses.
Figure 5.
A
Geographic distribution of members of the
P. juarezi
group.
B
,
C
Habitat at the type locality of
Pseudoeurycea jaguar
sp. nov.
Cupressus
forest, roots, trunk and branches of the trees have moss of the genera
Ptychomitrium
sp. and
Anacolia
.
Pseudoeurycea jaguar
sp. nov.
is mainly an arboreal species with nocturnal habits. The species was observed active at night on trees, shrubs, rocks, herbaceous plants, and moss and was also observed moving on the ground. Most of the trees where
P. jaguar
was observed contained layers of moss and bromeliads. By day, we found
P. jaguar
sp. nov.
hidden behind or within the layers of moss that cover the trunks of the trees, in particular two species of moss (
Ptychomitrium
sp. and
Anacolia menziesii
).
Other species of plethodontids that share habitat with
P. jaguar
sp. nov.
in the study site are
Aquiloeurycea cafetalera
,
Chiropterotriton
sp.,
Isthmura gigantea
,
Parvimolge townsendi
,
Thorius
sp. and
T. troglodytes
.
Intraspecific antagonistic behavior.
Antagonistic behavior between individuals in a population has been described in several species of plethodontid salamanders (
Jaeger and Forester 1993
;
Staub 1993
;
Lynn et al. 2019
). However, this behavior has been little studied or observed in Mexican plethodontids. During our population study, we only found one individual of
P. jaguar
in each trap or tree studied. Initially, we collected some individuals, transported them to the laboratory, and took morphological measurements for mark-recapture studies. On the first sampling trip, we kept three containers with more than one individual, considering that each container represented a particular section of the study area. In the first one, we kept five immature individuals with a large adult, in the second container a pair of adult individuals, and in the third container two large adult individuals with a young adult. In all the containers there were signs of serious aggression. In the first, three of the five juvenile individuals disappeared; in the second, the female and male adults mutilated each other, leaving the male blind and the female with serious injuries to the body; in the third container, the youngest individual was killed. Some individuals of the population studied have regenerated or regenerating tails, indicating some level of predation or possibly agonistic interaction between them.
Etymology.
The specific epithet
jaguar
is a noun in apposition and refers to the similarity between the dorsal color pattern of the salamander and that of the jaguar (
Panthera onca
). In the last three years the presence of this endangered feline has been recorded in some places in the Sierra de Zongolica and it seems appropriate to honor this emblematic species in the region.