Liolaemus casamiquelai, Avila, Luciano Javier, Perez, Cristian Hernan Fulvio, Morando, Mariana & Sites, Jack Walter, 2010

Avila, Luciano Javier, Perez, Cristian Hernan Fulvio, Morando, Mariana & Sites, Jack Walter, 2010, A new species of Liolaemus (Reptilia: Squamata) from southwestern Rio Negro province, northern Patagonia, Argentina, Zootaxa 2434, pp. 47-59 : 49-56

Liolaemus casamiquelai sp. nov.

( Figure 1 , 2 )

Type material. Holotype: MACN 39042, an adult male collected along the south side of Ruta Nacional 23, 14 km W Aguada de Guerra (41º 09’ S, 68º 30’ W, 866 m, Fig. 5 ), 25 de Mayo Department, Río Negro province, Argentina, 27 November 2000, by L. J. Avila, and C. H. F. Perez.

Paratypes: MACN 39043, MLP.S 2603, LJAMM-CNP 2986, LJAMM-CNP 4878 adult males; MACN 39044-5, MLP.S 2601-3, LJAMM-CNP 2977, LJAMM-CNP 2979- 80 adult females. Same data as the holotype. MLP.S 2600, LJAMM-CNP 2948, adult males; MACN 39041, MLP.S 2599, LJAMM-CNP 2949 adult females. Shrubby margins of Cari Lafquen Lagoon, 7 km N Ingeniero Jacobacci (41º 13’ S, 69º 24’ W, 855 m), 25 de Mayo Department, Rio Negro Province, Argentina, 28 November 2000 by L. J. Avila and C. H. F. Perez. LJAMM-CNP 11090- 92 adult males. Cari Lafquen Chica lagoon and Ruta Provincial 6, 10 km N junction Ruta Nacional 23 (41º13’ S, 69º24” W, 834 m), 25 de Mayo Department, Río Negro province, Argentina, 6 November 2008, by L. J. Avila, and M. Nicola. LJAMM-CNP 11102 adult males; LJAMM-CNP 11101 adult females. Ruta Nacional 23, 22.3 km E Ingeniero Jacobacci (41º18’ S, 69º17’ W, 860 m), 25 de Mayo Department, Río Negro province, Argentina, 7 November 2008, by L. J. Avila, and M. Nicola. LJAMM-CNP 11099, 11100 adult females. Ruta Provincial 74, 33.2 km N Chasicó (road to Aguada Guzman), 33.2 km N junction Ruta Provincial 6 (40º02’S, 68º54’ W, 876 m), El Cuy Department, Río Negro province, Argentina, 6 November 2008, by L. J. Avila, and M. Nicola. LJAMM-CNP 2973- 6 adult males. Ruta Provincial 6, 64 Km NE Ingeniero Jacobacci (40º53’, 69º17’, 854 m), 25 de Mayo Department, Río Negro province, Argentina, 29 November 2000, by L. J. Avila, and C. H. F. Pérez.

Diagnosis. Liolaemus casamiquelai is a robust and medium sized member of the clade of Liolaemus referred to as the boulengeri group by Etheridge (1995), and is a member of the Liolaemus melanops complex that includes L. canqueli , L. goetschi , L. martorii , L. melanops , L. morenoi , and several other candidate species still in need of detailed morphological study (Morando 2004; Avila et al. 2006a). Liolaemus casamiquelai can be distinguished from all other species of its group of Liolaemus by a combination of characteristics: its larger size, stout body, intense melanic venter, lack of melanic head, and bright green dorsal coloration with a pattern of transversal irregular black stripes ( Figs. 1 , 2 , 3 ). Liolaemus casamiquelai differs from L. canqueli and L. melanops in lacking a dark brown or black hood on the head in adults of either sex, and from L. goestchi and L. martorii in lacking large, black pre-and postcapular spots and these species are smaller. Liolaemus casamiquelai differs from L. morenoi in having a green background color with transverse black bands rather than a dorsal background color of light tan with brown spots or wavy with white posterior borders.

Description of the holotype. Adult male 92.7 mm (SVL), tail 131.0 mm. Axilla-groin distance 43.7 mm. Head length 17.7 mm; head width 14.9 mm; head depth 11.0 mm. Arm length 26.2 mm; tibial length 19.0 mm; foot length 26.4 mm.

Upper head scales smooth, convex, bulged, pitted with scale organs. Rostral pentagonal, twice as wide as high (3.17 x 1.4 mm). Two postrostrals, wider than high, nasal scales separate from rostral. Nasal scales subpentagonal in shape (1.8 x 1.7 mm). Nostrils roughly oval in shape, occupying almost half of the nasal scale. Nasal scales in contact with eight scales on each side. Internasal scales slightly convex. Four internasals, two in contact with postrostral, left almost rectangular, right quadrangular; two separate from postrostral by first internasal, almost oval in shape. Four frontonasals, two medials, hexagonal, in tandem, smaller than laterals. Left lateral frontonasals larger than right lateral scale. Nine prefrontals, regularly arranged, first row with a small medial, two large mediolateral and two smaller lateral; medial and laterals rhomboidal and similar in size, mediolaterals symmetric but roughly rectangular. Second row with two symmetric scales, regular and roughly pentagonal in shape, last row with two symmetric but smaller scales. Four small frontal scales almost similar in size than last prefrontals, in two rows. Eight frontoparietals irregular in shape, larger than frontal and parietal; arranged in three rows. Interparietal pentagonal with a large and conspicuous white cream “eye” in the middle, surrounded by five scales. Two large parietals, regularly arranged. Circumorbital circles incomplete: 13–14. Supraoculars 8–9, laterally expanded. Two rows of irregular, small scales between supraoculars and external circumorbitals, 11-15. Supercilliaries 7-7, first five strongly overlapped. Nuchal scales small, irregularly rounded, slightly bulged. Two internasals. First canthal higher than wide, separating first and second loreals, contacting lorilabials. Posterior canthal longer than wide. Posterior canthal overlaps only a small part of first supercilliary. Loreals: three irregular in size but symmetrically arranged on each side, two between first canthal and preocular. Canthals, preocular and anterior subocular forming a slight concavity. One preocular, slightly longer than wide; one elongate subocular (5.1 x 0.8 mm), one small postocular; a very evident keel in preocular and subocular, postocular with a less marked keel. Lorilabials convex to flat, 7-7, all roughly quadrangular, pitted with conspicuous and numerous scale organs. Upper ciliary scales in two rows, rectangular, compressed, and moderately projecting. Lower and upper ciliaries similar in size and shape. Palpebral scales small, irregular, convex. Supralabials 8-8, slighlty convex. Temporal scales rounded, smooth, convex, juxtaposed, with a scale organ in the tip. Auditory meatus higher than wide (3.4 x 1.2 mm) surrounded by granular scales. Mental pentagonal wider than high (2.9 x 2.0); in contact with anterior infralabial and postmental but not in contact with anterior sublabials. Infralabials 6-5. Chinshields 5-5, transversally expanded, separated from infralabials by series of 2-3 elongated but smaller sublabials. Only a few scale organs present in supralabials and infralabials. Gular scales smooth, flat, imbricate, rhomboidal, immediately after postmental, gradually becoming rounded posteriorly and with a distinct posterior apical notch. Lateral neck folds (longitudinal, oblique, antehumeral and post auricular) well developed. Antegular and gular folds not developed. Dorsal body scales subtriangular, slightly to not imbricated. Eighteen to 24 longitudinal rows with scales with distinct but smooth keels, a few with an apical scale organ. At midbody, dorsal scales laterally smooth, imbricate. Scales anterior to, above, posterior, and close to posterior forelimb and hind limb insertions, small, smooth, slightly overlapping, becoming granular. Ventral body scales smooth, flat, imbricate, with an apical notch in gulars; subtriangular to obovate, same size than dorsal body scales. Scales around midbody 72; scales between occiput an anterior margin of hind-limb articulations 76. Scales of cloacal apron more equal in size than ventral body scales. Preocloacal pores 7. Suprabrachials smooth, rhomboidal, imbricated, with a small notch in the tip. Infrabrachials small, convex, and not overlapping. Supra-antebrachials smooth, imbricate, rhomboidal to obovate, some with a small notch in the tip, others larger than suprabrachials. Infra-antebrachials smooth, rhomboidal, distally becoming with one to three small but distinct spines near the hand insertion. Supracarpals smooth, strongly imbricate. Infracarpals keeled, imbricate. Supradigital lamellae smooth, strongly imbricate. Subdigital lamellae tricarinate, imbricate, numbering: I: 12, II: 20, III: 20, IV: 16, V; 10. Suprafemorals smooth, imbricate, rhomboidal, few with an apical scale organ. Infrafemorals smooth, imbricate, rhomboidal. Supratibials smooth, imbricate, becoming rounded distally. Twenty six to 45 spinose scales in a postfemoral patch. Infratibials smooth, imbricate. Supratarsals, smooth, imbricate, a few with an apical notch. Infratarsals strongly imbricate, with one keel, and one to three small but distinct spines near the digits insertion. Supradigital smooth, imbricate. Infradigital bi- to tri-carinate, numbering I: 11, II: 16, III: 23, IV: 29, V: 18. Ventral caudal scales smooth, a few slightly keeled, imbricated. Dorsal caudal scales keeled, imbricated.

Coloration. In life, general background color on neck, body, tail, and limbs, brightly green-yellow (in sunlight) becoming gray/light gray in the shade. Dorsal head surface irregularly brown intermixed with smaller, irregular gray areas, grading to light tan in azygous and nuchal areas. Between occiput and rump, a series of twelve more or less regular, transversal black bands, 2-5 scales wide, more regular in the midbody between limbs. First two marks on the nuchal area irregularly divided and merged, limiting clear spots with background coloration. Markings continue on the lateral sides of the head and neck as irregular well-marked lines 1-2 scales wide, becoming faded and gray on the ventral surface. On the lateral sides of the head, clear areas are larger and clear-white. On the trunk dorsum, transversal marks are broken, or slightly connected along vertebral midline. Some marks between limbs become forked on the lateral regions of the trunk. All marks between limbs extend, usually well defined, to the ventral scales. Between legs and first third of the tail, transverse marks merge and become more regular. Along the tail transverse marks merge longitudinally and become almost indistinguishable in the last third of the tail. Background coloration becomes light-gray on distal two-thirds of the tail. Lower lateral sides of the neck, trunk, and first third of the tail orange-yellow when lizard is in the shade without bright coloration. Otherwise, no lateral color differs from the general background. On dorsal limb areas an irregular pattern of black lines, continuous from the dorsum, delimit rounded or irregular, clear spots with a light gray background. Ventral surfaces of the gular, chest, belly, interfemoral, femoral and apron areas black. Ventral surface of the limbs and tail white with some gray areas. All bright coloration disappears after capture, and after several years in preservative, all coloration became faded.

Variation. Based on the paratypes ( Table 2 , Fig. 4 ): in 15 males: SVL 78.8–106.2 mm. Axilla groin distance 37.8–54.5 mm. Foot length 15.6–27.1 mm. Tibial length 16.2–19.6 mm. Arm length 22–28.5 mm. Head length 15.1–18.8 mm. Head width 13.1–16.2 mm. Head depth 9.5–13.8 mm. Midbody scales 64–78. Dorsal scales between occiput to rump 66–87. Ventral scales 92–109. Supralabials 6–9. Infralabials 5–7. Fourth toe lamellae 27–32. Precloacal pores 7–11. In 15 females: SVL 74.1–103.5 mm. Axilla-groin distance 38.3–56.4 mm. Foot length 21.8–27.0 mm. Tibial length 15.3–18.2 mm. Arm length 22.1–26.6 mm. Head length 13.9–18.2 mm. Head width 12–15.0 mm. Head depth 9.1–11.6 mm. Midbody scales 66–76. Dorsal scales between occiput to rump 75–84. Ventral scales 96–115. Supralabials 5–9. Infralabials 5–7. Fourth toe lamellae 25–33. Dorsal head scales variable in size, some irregular in shape, most convex but a few almost flat. Cloacal apron larger in males that in females. Scales of the cloacal apron slightly smaller that ventral scales in males, same size or slightly smaller in females. Postfemoral patch not present in females and variable in size in males between 18–22 scales.

Males (N= 15) Females (N= 15)

In some individuals melanic coloration is more extensive than the holotype. In a few individuals dorsal transversal marks are connected longitudinally, becoming lines of clear dots on the dorsum. In some individuals melanic coloration extends on lateral sides of the neck and head, leaving only a few clear scales; others have the same areas with a very reticulated pattern of anastomosed gray lines. All individuals show a bright yellow-green coloration in full sun, which immediately fades in the shade and disappears completely when lizards are kept in captivity. Dorsal background color bright green in recently captured adult males and females, few individuals (20-30%) have a yellowish-green sheen. Individuals from locality Ruta Nacional 23 10 km E Ingeniero Jacobacci have a grey background coloration on the head and tail.

Etymology. To honor Rodolfo Magín Casamiquela, a recently deceased vertebrate paleontologist and anthropologist, born in Ingeniero Jacobacci (formerly Huahuel Niyeu) in 1932, a small town very close to L. casamiquelai type locality. R. M. Casamiquela was a researcher (retired) of Consejo Nacional de Investigaciones Científicas y Técnicas of Argentina (CONICET), and developed a large and prolific scientific and cultural literature ranging from amphibians fossils to historic tales of Patagonia.

Geographic distribution. Liolaemus casamiquelai is known from five localities ( Fig. 6 ) in western Rio Negro province: (1) the type locality, (2) in the eastern edge of Cari Lafquen Chica Lagoon, (3) along the National Road 23 eastern of Ingeniero Jacobacci town, (4) 64 km north of Ingeniero Jacobacci along the Provincial Road 6, and (5) south of Aguada Guzman town, along the Provincial Road 74.

Natural history. The holotype and the paratypes were found basking on the edges or walking inside of clumps of spinose shrubs. All localities except (5) are in Meseta Central ecoregion ( Bran et al. 2000), the most arid region in Río Negro province, with an annual rain lower than 200 mm and temperatures between 10-12° C. This ecoregion is characterized by the presence of lower plateaus, small hills, and peneplains covered by lower-shrub steppe vegetation with dominant plants as Nassauvia axillaris , N. glomerulosa , and Chuquiraga avellanedae or shrub-grass steppes with clumps of Prosopis denudans and Lycium sp, surrounded by grassy areas with several species of grass, more common is Stipa humilis . The fifth locality is an ecotonal area between southern Monte and the Meseta Central ecoregion, with the same vegetation plus some individuals of Larrea spp. and clumps shrubs of Schinus johnstonni . According to Cabrera (1994) phytogeographic classification, all the localities are included in the Dominio Andino Patagónico, Provincia Patagónica. All of the sites where L. casamiquelai were collected are similar in physiography, normally flat, with sandy soil mixed with gravel areas or more compacted soil. Clumps of shrub appear in areas with some degree of protection from the strong winds typical of Patagonia; these clumps are composed mainly of Prosopis denudans (or Schinus johnstonii in locality 5) and smaller shrubs of Atriplex sp., Lycium chiliensis , and Chuquiraga avellanedae , all of which grow under the protection of this spiny mesquite. These clumps reach a maximum height of 1.8 m, and cover an area between two to four m2 and separated from each other by distances of two or three meters. This region is characterized by highly degraded soils (due to overgrazing), and shows a tendency towards desertification. Clumps seem to be the safest areas for lizards and rodents, as well for some birds. The majority of the lizards were observed only inside or in the immediate vicinity of the spiny shrub clumps. We never observed a lizard in small shrubs or between grasses surrounding this clumps. All lizards observed during several field trips were seen in the immediate edges or inside the clumps. Usually lizards bask under sun in early morning (09:00 to 10:00) and in late afternoon (18:00 to 19:00) in the midsummer, when they show a bimodal type of activity, but in early spring and late-summer they usually show continuous activity without a mid-day break. In the type locality we collected other species of Liolaemus living in syntopy with L. casamiquelai , including L. inacayali , L. bibronii , and L. aff. melanops , as well as two leiosaurid species Leiosaurus bellii and Pristidactylus nigroiugulus Avila et al. (2003) . In other localities we collected Liolaemus elongatus , L. petrophilus , Phymaturus aff. ceii , and Homonota darwinii usually in nearby rocky outcrops but not sharing the same microhabitat than L. casamiquelai ( Acosta et al. 1996a, b; Avila et al. 2003; Avila et al. 2004; Avila et al. 2006a, b). In nearby localities we collected Bothrops ammodytoides and Philodryas patagoniensis ( Avila et al. 2001) , both are known to eat lizards and are probable predators of L. casamiquelai . Some other likely predators, such as the hawks Falco sparverius and Buteo polyosoma , are common in this area. Liolaemus casamiquelai is probably oviparous as well others members of its clade, and feeds mainly in arthropods and some plant matter as a dissected stomach content show.

Remarks. Phylogenetic analysis based on the mitochondrial gene fragment cyt-b (805 bp), using Maximum Parsimony and Bayesian approaches of all described species of the fitzingerii group ( melanops + fitzingerii complexes) and two outgroups ( L. boulengeri and L. cuyanus ) recovered the tree shown in Fig. 7 . This topology presents evidence to support the monophyly of the melanops complex with L. casamiquelai as the sister taxon of L. martorii (MP Bootstrap Support [MPB]: 90; Posterior Probability [PP]: 0.51) and closely related to L. goestchi . Liolaemus morenoi is the basal species of this clade we call melanops N (MPB: 83, PP: 0.99). Liolamus canqueli is the sister taxon of L. melanops , clade we refer to as melanops S (MPB: 96, PP: 0.94). The uncorrected pairwise distances within species of the melanops N clade range from 0.62% ( L. goestchi vs. L. casamiquelai ) to 2.73% ( L. morenoi vs. L.martorii ); the distance between L. canqueli vs. L. melanops is 1.74%; and species distances between melanops N and S clades range from 3.11% to 3.85%. There is evidence of incomplete lineage sorting for this marker within and between these clades (Morando et al., in prep.), and species from this complex (as in other Liolaemus complexes) exhibit strong variation in background and pattern coloration that difficult an easy recognition of species limits without a proper sampling effort and an adequate knowledge of contact zones. A poor morphological knowledge of large series, lack of extensive sampling, absence of revision of type specimens, fail to collect samples in the right type locality made difficult an adequate study of the species of the complex and originated a complicated nomenclatural status for some of them. But a discussion of the nomenclatural status of some species and our vision of the present situation of this complex is out of the scope of this work. Some authors do not recognize L. martorii and suggested synonymy with L. goetschi ( Cei & Scolaro 2003, Pincheira et al. 2008) but our recommendation is to be conservative until intensive serious studies present convincing evidence for species limits in this group; until then, we still recognize L. martorii as a valid species well characterized with some morphological traits (see Abdala 2003) even the molecular paraphyly discovered for some individuals in Avila et al. (2006). These species as well as other undescribed taxa from this group are under study by our research group and a detailed analysis will be published elsewhere.

Figures

FIGURE 1. Liolaemus casamiquelai, holotype adult male (MACN 39042), from southern edge of Ruta Nacional 23, 14 km W Aguada de Guerra, 25 de Mayo Department, Rio Negro province, Argentina.

FIGURE 2. Dorsal (upper) and ventral (below) view of the Liolaemus casamiquelai, holotype.

FIGURE 3. Liolaemus casamiquelai (A) and the other species in its clade: L. morenoi (B), L. martorii (C), L. melanops (D), L. goetschi (E), and L. canqueli (F). All males from the type localities. Liolaemus goetschi (type specimen) photograph courtesy of the Zoologische Staatssammlung München through Dr. K. Delhey

FIGURE 4. Variation in some individuals of the type series. Dorsal and ventral color variation in some individuals of the type series of Liolaemus casamiquelai showing variation in dorsal and ventral coloration; only individuals showing extreme variation are included.

FIGURE 5. General view of the type locality of Liolaemus casamiquelai from a northern perspective. Lizard activity was observed only under large clumbs of shrubs.

FIGURE 6. Known distribution of Liolaemus casamiquelai (red dots; 1 = Ruta Nacional 23, 14 km W Aguada de Guerra; 2 = eastern edge of Cari Lafquen Chica Lagoon; 3 = along the National Road 23 eastern of Ingeniero Jacobacci town; 4 = 64 km north of Ingeniero Jacobacci along the Provincial Road 6; and 5 = south of Aguada Guzman town, along the Provincial Road 74. The major geographic landmarks are illustrated, and the insert identifies this area in Argentina.

FIGURE 7. Phylogenetic relationships of the Liolaemus melanops complex with other described members of the fitzingerii group. Numbers above branches are MP bootstrap values.

Tables

TABLE 2. Morphometric and meristic variation in the Liolaemus casamiquelai type series. Means and standard deviations (SD) of the main morphometric and meristic characters. Measures in mm and scale in numbers.

	Mean	SD	Range Mean	SD	Range
SVL	92.78	6.48	78.8–106.2 91.75	7.8	74.15–103.5
Axilla-groin distance	46.07	3.94	37.84–54.57 49.87	5.26	38.31–56.49
Head length	17.58	1.29	15.15–18.88 16.48	1.21	13.95–18.20
Head width	14.95	1.17	13.1–16.24 13.99	0.87	12.00–15.08
Head high	10.89	1.04	13.1–16.24 10.32	1.79	9.10–11.65
Foot length	25.11	2.77	15.65–27.15 24.54	1.44	21.80–27.06
Tibial length	18.00	1.19	16.25–19.6 17.05	0.90	15.35–18.24
Arm length	25.73	1.64	22.00–28.52 24.81	1.50	22.10–26.60
Midbody scales	71	4.38	64–78 70.29	3.15	66–76
Dorsal scales	78.13	5.15	66–87 79	3.18	75–84
Ventral scales	100.8	5.0	92–109 103.7	5.58	96–115
Fourth toe lamellae	29.26	1.48	27–32 29.11	2.14	25–33
Supralabial scales	7.66	1.17	9–6 7.70	1.04	5–9
Infralabial scales	6	0.75	5–7 6.05	0.65	5–7
Cloacal pores	8.33	1.18	7–11 -	-	-