Phymaturus aguanegra, Lobo, Fernando, Laspiur, Alejandro & Acosta, Juan Carlos, 2013

Lobo, Fernando, Laspiur, Alejandro & Acosta, Juan Carlos, 2013, Description of new andean species of the genus Phymaturus (Iguania: Liolaemidae) from Northwestern Argentina, Zootaxa 3683 (2), pp. 117-132 : 120-122

Phymaturus aguanegra sp. nov.

Holotype ( Fig 1 .): MCN 975. Male. Paso Agua Negra, Iglesia department, San Juan province, Argentina. 30º23’ S; 69º34’ W. 2900 m asl. April 2007. A. Laspiur, E. Sanabria & L. Quiroga collectors.

Paratypes: MCN (969, 973-975, 977, 979, 982, 984, 988, 990-991, 995 and 971-972, 976, 978, 980, 981, 983, 986-987, 989, 992-993). 13 males and 14 females. Same data as holotype.

Diagnosis. Phymaturus aguanegra belongs to the palluma group (sensu Etheridge 1995) because it has square, non-imbricate superciliaries, scales of the tail markedly spinose, usually a fragmented subocular, and the subocular-supralabials are separated by two or more scale rows. This new taxon belongs to the Puna subclade of the palluma group (Lobo & Quinteros 2005) because it shows the typical dorsal “spray” pattern (southern palluma group members show a dorsal reticulated pattern).

Within the Puna subclade, Phymaturus aguanegra differs from P. antofagastensis , P. punae and P. laurenti because it presents a complete melanism over the dorsum of neck, whereas the other three species exhibit a clear interruption in the mid dorsal line ( Figs. 2 A and B). Phymaturus aguanegra differs from P. antofagastensis and P. punae in the presence of enlarged scales at the base of tail in males, which are absent in these two species (see this character in Fig. 15B of Lobo et al. 2010a). Phymaturus aguanegra has strongly keeled tarsal scales, differing from P. laurenti (slightly keeled). Tail of males and females of Phymaturus aguanegra lacks a pattern, whereas in P. antofagastensis , P. punae , P. laurenti , and P. mallimaccii the tail of females is always ringed, and the tail of males of P. mallimaccii and P. punae is ringed (not as marked as in females); however, in males of P. antofagastensis and P. l a u re n t i the ringed pattern may be present or absent (see this character in Fig. 10C of Lobo & Quinteros 2005b). Phymaturus aguanegra lacks enlarged scales on the anterior margin of the antehumeral fold and centre of chest, as in P. antofagastensis and P. laurenti ( Fig.2 C and D). Females of P. aguanegra lack flank coloration, whereas in P. antofagastensis (yellow), P. mallimaccii and P. laurenti (orange), coloration is conspicuous. A vertebral dark gray stripe is usually present on the dorsum of Phymaturus aguanegra , whereas in P. antofagastensis and P. laurenti , it is always absent. In P. punae and P. mallimaccii this vertebral stripe is light gray. Females of Phymaturus aguanegra lack transversal white stripes on the dorsal pattern, as females of P. antofagastensis and some females of P. laurenti (see this character in Fig. 10A of Lobo et al. 2010a). Females and, to a lesser extent, males of P. aguanegra exhibit a tricolor dorsal pattern, with two shades of brown and scattered ferriferous oxide spots; this pattern is not found in any other species of the group, except the species we describe below and P. paihuanense . Phymaturus aguanegra lacks a scapular spot, present in P. mallimaccii and P. extrilidus . Rostral scale is always undivided in Phymaturus aguanegra , whereas it can be divided in P. antofagastensis and P. punae . Sexual dichromatism is more pronounced in P. punae , P. antofagastensis , P. mallimaccii , and P. laurenti than in P. aguanegra , in which the dorsal pattern of males is slightly yellow or inconspicuous. Phymaturus aguanegra differs from the recently described Chilean species P. paihuanense ( Núñez et al., 2010) in the presence of dorsal melanism of head and neck (absent in P. paihuanense ), in having scales not enlarged on the anterior margin of the antehumeral fold (present in P. paihuanense ) and differs from P. damasense ( Troncoso-Palacios & Lobo 2012) in the presence of non-projected scales on the anterior border of auditory meatus (present in P. damasense ) and in the color pattern of males and females.

Description of holotype. Male. Snout-vent length 95.3 mm. Head length 17.6 mm. Head width 16.7 mm. Head height (at parietal) 9.8 mm. Axilla-groin 51.4 mm (53.9 % of Snout-vent length). Tail length (excluding the regenerated part) 61.5 mm. Body slightly wide, trunk width: 36.4 mm (38.2 % of SVL). Twenty-two smooth dorsal head scales. Three scale organs in one postrostral and none in the other three postrostrals. Nasal bordered by nine scales, not in contact with rostral. Canthal separated from nasal by three scales. Loreal region slightly concave. Ten enlarged supralabial scales, none in contact with subocular. Ten enlarged infralabials. Auditory meatus oval, without enlarged scales in its anterior border. Auricular scale absent. Eleven convex, juxtaposed temporals. Rostral undivided. Mental subpentagonal, in contact with six scales. Interparietal bordered by eight scales. Frontal region without an azygous scale. Supraorbital semicircles inconspicuous. No distinctly enlarged supraoculars. Eleven imbricate flat superciliaries. Subocular unfragmented separated from supralabials by one to two rows of lorilabials. Seventeen lorilabials, the last subocular. Preocular separated from lorilabial row by four scales. Scales of throat round, flat, and juxtaposed. Chin shields undifferentiated. Sixty-six gulars between auditory meata. Lateral nuchal folds well developed, with granular scales over longitudinal fold. Antehumeral pocket well developed. Fifty-eight scales between auditory meatus and shoulder. In ventral view, gular fold not developed and posterior gular folds present with their anterior margins without enlarged scales on their borders. Lack of enlarged scales in the centre of chest. Dorsal scales round, smooth, juxtaposed. Forty-four dorsal scales along midline of the trunk in a distance equivalent to head length. Scales around midbody: 198. Mid-dorsal scales not enlarged compared with those on flanks. Ventral scales larger than dorsals. Ventral scales between mental and precloacal pores: 182. Eight precloacal pores in an undivided row plus one supernumerary pore. Brachial and antebrachial scales smooth with rounded posterior margins. Supracarpals laminar, round, smooth. Subdigital lamellae of fingers with three keels. Number of subdigital lamellae of fingers I: 8; II: 13; III: 15; IV: 20; V: 13. Claws moderately long. Supradigital lamellae convex, imbricate. Infracarpals and infratarsals with round margins and 2-3 obtuse mucrons. Supracarpals and supratarsals smooth, with round posterior margins. Subdigital lamellae of toes I: 9; II: 13; III: 17; IV: 23; V: 17.

Pattern of body and limbs: body trunk and dorsal surfaces of fore and hindlimbs covered by thinly scattered brown spots. No conspicuous pattern is present, except dorsum of neck and head, which becomes dark, almost melanic ( Fig. 1A &B). This dark color is extended over the sides of head and throat. Melanism can reach the chest.

Coloration in life: the general background coloration is brown-orange, giving an appearance of ferric oxide coloration ( Fig. 2 ). In a few specimens a light yellow dorsal color can be observed.

Variation: Based on 28 adult specimens (13 males and 15 females). SVL 70.9-98.5 mm (x = 85.6; SD = 9.1) for adult specimens only. Head length 15.8–20.6% (x = 18.8%; SD = 1.1) of SVL. Tail length 0.85–1.06 (x = 0.93; SD = 0.06) times SVL. Scales around midbody 165–220 (x = 191.7; SD = 13.3). Dorsal head scales 20–27 (x = 23.4; SD = 1.9). Ventrals 163–194 (x = 181.1; SD = 9.2). Scales surrounding interparietal 7–11 (x = 9; SD = 0.9). Scales of neck along longitudinal fold from posterior border of auditory meatus to shoulder 54–70 (x = 63.2; SD = 4.4). Gulars 56–98 (x = 74.3; SD = 11.4). Scales between rostral and frontal 8–12 (x = 9.5; SD = 1.3).

Etymology. The specific epithet is given after its type locality. [“Agua Negra”] toponym, which refers to the dark water aspect of Andean streams near the type locality

Distribution. Only known from its type locality.

Figures

FIGURE 2. Patterns of coloration in life of Phymaturus aguanegra sp. nov. A and B: Males; C and D: Females.

FIGURE 1. A. Dorsal view of the holotype specimen of Phymaturus aguanegra sp. nov. (MCN 975) B. Ventral view of the same specimen. SVL: 95.3 mm.