The limits of polymorphism in Liolaemus rothi: Molecular and phenotypic evidence for a new species of the Liolaemus boulengeri clade (Iguanidae, Liolaemini) from boreal Patagonia of Chile
Author
Pincheira-Donoso, Daniel
Author
Scolaro, Alejandro
Author
Schulte, James A.
text
Zootaxa
2007
1452
25
42
journal article
10.5281/zenodo.176292
ae401c40-a319-472f-a705-27442c8cdad2
1175-5326
176292
Liolaemus hermannunezi
sp. nov.
Figures 2
and
4
Liolaemus rothi
Donoso-Barros (1974:287)
;
Núñez and Jaksic (1992:76)
;
Pincheira-Donoso (2003a:18)
; Schulte
et al.
(2004:410).
Liolaemus (Eulaemus) rothi
Pincheira-Donoso and Núñez (2005:99)
.
Type
material
.
Holotype
. MNHNC-3785, male, collected
10 km
E from Los Barros (
37°31’S
;
71°15’W
) on the road to Pichachén Pass, Eighth Administrative Region,
Chile
,
18 November 2001
by D. Pincheira- Donoso.
Paratypes
. MNHNC-3501, male, same locality as
holotype
, collected
10 February 2001
by J. A. Schulte II and J. P. Valladares; MNHNC-3502, 3503, both females, same data as male
paratype
; JAS-DC-718, female, same data as
holotype
; CHDPD-995, female, same data as
holotype
.
Etymology.
This species is dedicated to Herman Núñez, from the National Museum of Natural History of
Chile
, in recognition of his great contribution to the systematics and ecology of Chilean lizards of the genus
Liolaemus
. DP-D particularly thanks his teachings, his intimate friendship and his persistent help and encouragement.
Diagnosis
. A small bodied
Liolaemus
species belonging to the
boulengeri
clade diagnosed by
Etheridge (1995)
, as having a femoral patch of abruptly enlarged scales on the posterior surface of the thigh, and by the hypertrophied puboischiotibialis muscle (recently recognized as flexor tibialis internus;
Abdala
et al.
2006
), a trait well-developed in adult males. Into the
boulengeri
clade,
Etheridge (1995
, 2000) also recognized the
wiegmannii
species group, which is characterized by lorilabials distinctly smaller than supralabials, usually in two rows between the subocular and supralabials, with the posteriormost not elongate, with sublabials contacting the mental shield, which is widest posteriorly, and infralabials flat to concave. However, traits of the
wiegmannii
group are not observed in
L. hermannunezi
, and morphology and coloration differentiate
L. hermannunezi
from most of the remaining species belonging to the
L. boulengeri
clade, except
L. loboi
,
L. rothi
,
L. sagei
and
L. tehuelche
.
Liolaemus hermannunezi
differs from
L. tehuelche
in having a black belly, a smaller body size (
49.1–64.1 mm
; mean =
53.1 mm
), and a distribution restricted to the Laguna del Laja in
Chile
(
37°31’S
;
71°15’W
), whereas
L. tehuelche
is only black on the throat, has a larger body size (
55.5–74.2 mm
; mean =
66.4 mm
), and a more austral distribution in
Argentina
(
40°44’S
;
70°34’W
).
Liolaemus hermannunezi
differs from
L. sagei
in having a smaller body size (see above), larger and fewer body scales (Table 1), and has ventral melanism, mainly in abdominal and gular areas, whereas
L. sagei
is uniformly grey or blue ventrally. From
L. rothi
,
L. hermannunezi
differs in having a smaller body size (SVL over
100 mm
in
L. rothi
; see above), smaller and therefore more body scales (Table 1), and a black belly in males, restricted to the gular region in females. This last trait is absent in
L. rothi
(Table 1). Finally,
L. hermannunezi
differs from
L. loboi
in having a smaller body size (see results for statistical comparisons), a higher number of scales around the middle of body (range in
L. hermannunezi
= 66–77, mean = 71.8; versus range in
L. loboi
= 59–70, mean = 63.7), is black ventrally, and has a more boreal distribution in
Chile
, whereas in
L. loboi
ventral melanism is conspicuous, and occurs in more austral areas in
Argentina
(see Results for details, also
Fig. 5
, Table 1).
FIGURE 2.
(a) Adult male of
L. hermannunezi
in life. Specimen collected approximately 8 km E of Los Barros, Laguna del Laja, Chile; (b) adult female from the same locality. Photos J. A. Schulte.
Description of the
Holotype
– A small lizard with a relatively stout body. Snout-vent length
53.3 mm
, axilla-groin distance 24.0 mm. Head slightly longer (
12.6 mm
) than wide (
10.7 mm
). Head height
7.8 mm
. Snout moderately large. Neck as wide as head, with a shallow lateral fold, extending from posterior edge of external auditory meatus to insertion of the forelimb, forming an antehumeral fold and deep antehumeral pocket. Dorso-cervical and hemigular folds absent. Forelimb length
22.2 mm
.
Hind
limb length
34.9 mm
. Toe tips of adpressed hind limb reach posterior edge of external auditory meatus. Tail
88.7 mm
long, cylindrical, longer than snout-vent length.
FIGURE 3.
Phylogenetic relationships among 67 Liolaemini taxa based on maximum parsimony analysis of 1710 aligned positions of DNA sequence data (length = 5810 steps). Strict consensus of five equally most parsimonious trees. Bootstrap values are presented above branches and decay indices are shown in bold below branches on the cladogram.
Dorsal head scales slightly convex and smooth. Rostral pentagonal, expanded laterally, contacting six smaller scales. Two tiny pentagonal postrostrals. Nasal contacting seven smaller scales, surface twice as large as interparietal shield. A single row of four azygous scales surrounded by 10 frontonasals. Two prefrontals. Frontal divided transversely and longitudinally into seven small scales of similar size, 3–4 times smaller than prefrontals. Three postfrontals arranged in a transverse row, directly in contact with interparietal, hexagonal, and slightly larger than postfrontals. Parietals irregular, twice as large as interparietal, and with a smaller scale inserted between them. Occipital scales homogeneous, small, irregular, juxtaposed. Supraorbital semicircles convex. Circum orbitalis consisting of 13–13 small scales. Supraoculars 6–6, hexagonal, and wider than long, larger than other dorsal head scales. Superciliaries imbricate. Two rows of scales between supraoculars and superciliaries. Upper-ciliary scales 15–14, and 12–10 lower-ciliaries. Suboculars and postoculars enlarged, first one contacting an irregular polygonal preocular. Loreal region slightly concave, covered by three small scales, medial larger than other two. Supralabials 7–7, posteriors three times longer than anteriors. A single and irregular row of loreolabial scales between subocular and supralabials. Temporal subcircular, smooth, and subimbricate. Frontonasal, loreals, canthal, supralabials, loreolabials, temporals, and supraorbitals with tiny scale organs.
FIGURE 4.
Holotype of
Liolaemus hermannunezi
, male, MNHNC 3785, from 10 km E of Los Barros, near Pichachén Pass, Eighth Region, Chile. Photo D. Pincheira-Donoso.
FIGURE 5.
Map of the North-Western Patagonia of Argentina and Chile, showing the distribution of
Liolaemus hermannunezi
(black circle),
L. rothi
(empty circles),
L. sagei
(cross), and
L. loboi
(black triangle). Details on the wide Patagonian geographical distribution of
L. rothi
can be found in Cei (1986)
Mental subtriangular, slightly wider than rostral, bordered by two lower labials and two postmentals. Two divergent rows of 7–8 postmental scales, posteriors smaller than anteriors. Infralabials 6–7, larger than supralabials, smaller than those in posterior region. Single row of sublabials between postmentals and infralabials, that turn into two rows under second infralabial and in three rows under fifth infralabial. Gulars subcircular, smooth, and imbricate. External auditory meatus higher than wide, smaller than orbit, surrounded by several tiny granular scales, with two large scales along anterior margin, and conspicuous auricular scale in dorsal margin.
Dorsal body scales subtriangular and subimbricate, strongly keeled, never mucronate, lacking interstitial granules. Scales of body flanks similar to dorsals, but become smooth, with tiny interstitial granules. Ventral body scales 1.5 times larger than dorsals, rhomboidal, smooth, and imbricate, subtriangular and smaller in precloacal region. Scales around midbody 66. Lateral neck folds covered by several tiny granular scales. Similar scales on shoulders, axilla, and cloacal regions.
Forelimb scales subtriangular, imbricate, and slightly keeled, becoming smooth on dorsal surface of front feet. Lower humeral region covered by granular, juxtaposed tiny scales, becoming larger and subimbricate on forearm.
Hind
limbs with rhomboidal, slightly keeled, and subimbricate-imbricate scales, with a few tiny interstitial granules. Ventral scales of hind limbs rhomboidal, smooth, and imbricate. Coxal scales never projected. Posterior surface of thighs with a patch of abruptly enlarged scales. Twenty six strongly keeled subdigital lamellae on the fourth toe of right foot. Dorsal and lateral caudal scales rhomboidal, strongly keeled, becoming distinctly rectangular on distal tail. Ventral scales of the tail subtriangular, smooth, and imbricate, longer and keeled distally. Nine precloacal glands.
Coloration (on the basis of the entire
type
series)
– The ground colour in living specimens is grayish or brownish olive on the dorsal head and body surfaces, becoming gray or blue in preserved animals. Head with irregular and small brown, black, and white spots. Suboculars and supralabial scales white, with indistinct gray spots. Two fine (1–2 scales wide) white dorsolateral stripes run from superior margin of nasals, to tail base. Nine subcircular paravertebral black spots, similar or larger in size than orbit (each 19–25 dorsal scales), bordered by gray and white tiny marks, and arranged alternately or in pairs, in two parallel and longitudinal rows, most conspicuous at tail base. Prescapular and postcapular spots black and conspicuous. Fine (1–2 scales wide) white stripe on dorsal neck, normally fragmented on the back. Flanks with white ventrolateral stripe and black spots, slightly smaller than paravertebral ones, and bordered by tiny white and blue irregular spots in upper region. Flanks with distinct yellow scales in life. The same pattern is represented on the dorsal tail surface, being clearly more irregular. Distinct black, grey, and white spots are irregularly distributed on the dorsal surface of limbs.
Pale gray-whitish ground colour ventrally, but black on mid-belly and gular surface. Lower ventrolateral field irregularly scattered with small brown marks. Ground colour of ventral limbs similar to ventral body. Ventral tail unspotted, with small and indistinct gray marks in postcloacal region. Precloacal region pale. Precloacal glands orange. In preserved specimens ventral colour fades pale blue.
Variation
. No obvious differences were detected between sexes, except in precloacal glands, developed in males and totally absent in females. Also, ventral and gular melanism is slightly more conspicuous in males.
Frontonasal azygous 2–4, frequently with small supernumerary scales. Frontal region transversely and longitudinally divided, resulting 6–8 similarly sized small frontals. Single transverse row of 3–5 postfrontals behind frontal. Parietal scales irregular, smaller, equal, or larger than interparietal shield, frequently separated by tiny supernumerary scales. Supraorbital semicircles surrounded by 13–16 small scales. Supraoculars 4–7 on each supraorbital semicircle. Upper ciliaries 13–15, and 10–13 lower ciliaries. Loreals 3–6, polygonal, variable in size. Anterior supralabials similar or larger than the posterior ones, 7–9 on each side; 2–3 enlarged scales on anterior margin of external auditory meatus. Single auricular shield differentiated. Two divergent rows of 5–8 postmental scales contacting mental. Infralabials 6–7, similar or slightly larger than supralabials.
Dorsal body scales rhomboidal or subtriangular, keeled, subimbricate or juxtaposed, often with interstitial granules. Scales around midbody 66–77. Ventral body scales with negligible variation. Dorsal scales of forelimbs rhomboidal or sublanceolate. On hind limbs, dorsal scales rhomboidal, slightly keeled, imbricate or subimbricate, with interstitial granules. Fourth toes with 24–27 subdigital lamellae. Dorsal tail scales subcircular or subtriangular, keeled and imbricate, becoming more polygonal medially. Ventral scales of tail subcircular or subtriangular, smooth and imbricate, becoming more triangular and keeled medially. Precloacal glands 7–9, restricted to males.
Geographic distribution.
Liolaemus hermannunezi
is only known from the
type
locality (
Fig. 5
).
Natural history.
We know little about the biology of
L. hermannunezi
. It is diurnal and inhabits mountainous areas of the Patagonian steppe with short (<
0.5 m
), bushy vegetation growing on sandy-gravel substrata. This vegetation is used almost exclusively for refuge and on several occasions individuals entering vegetation were found buried in loose sand at the base of the shrub. Nothing is known about its diet or reproductive mode. Individuals were never found under or basking on rocks. The vegetation in the
type
area is characterized by
Acaena pinnatifida, Agrostis
serranoi, Arenaria serpens, Berberis empetrifolia, Chaetanthera lycopodioides, Cyperus reflexus, Epilobium nivale, Erigeron andicola, Gaultheria pumila, Geranium sessiliflorum, Haplopappus diplopappus, Heliotropium geissei, Hypochaeris
spp.,
Plagiobothrys myosotoides, Plantago
lanceolata, Poa
sp.,
Rumex acetocella
,
Spergularia rubra
,
Trifolium
spp., and
Viola subandina
(M. Molina-Montenegro, pers. comm.).