Marinussaurus curupira, Peloso & Pellegrino & Rodrigues & Ávila-Pires, 2011

Peloso, Pedro L. V., Pellegrino, Katia C. M., Rodrigues, Miguel T. & Ávila-Pires, Teresa C. S., 2011, Description and Phylogenetic Relationships of a New Genus and Species of Lizard (Squamata, Gymnophthalmidae) from the Amazonian Rainforest of Northern Brazil, American Museum Novitates 2011 (3713), pp. 1-24 : 5-13

Marinussaurus curupira , new species.

Figures 1-3 , 4A ; table 1

HOLOTYPE: INPA 19855 (Field Number, Ponte 73; fig. 1); adult male, collected at “Ramal km 27,” Iranduba , state of Amazonas, Brazil (no coordinates available), on August 30, 2007, by. V. T. Carvalho.

PARATYPE: INPA 19856 (Field Number, Ponte 41; figs. 2, 3); adult male, collected at Sítio Bom Lugar (Renato Cintra), Iranduba, Amazonas, Brazil (3°07′00″S; 60°19′01″W), on August 27, 2007, by V. T. Carvalho .

DIAGNOSIS: The same as generic definition plus the following additions: Maximum SVL (considering the two known specimens) 56.2 mm. Limbs relatively short and robust; all digits clawed. Three supraoculars; interparietal shorter than parietals; five occipitals of nearly the same size; few temporals (5–6); loreal large, in contact with supralabials, frenocular small; third pair of chin shields with a short medial contact, almost totally separated by two enlarged pregular scales, and in contact with fourth and fifth infralabials. It is further characterized by having 29 transverse rows of hexagonal, slightly imbricate, smooth dorsal scales between interparietal and posterior level of hind limbs; 20 transverse rows of quadrangular, slightly imbricate, smooth ventrals between collar and preanals; 30–31 scales around midbody; three femoral pores and two preanal pores on each side in males (females unknown); preanal pores separated medially by the anterior preanal scale; preanal plate formed by an enlarged anterior, and five posterior scales; 7–8 lamellae under fourth finger, some divided, and 13 under fourth toe, all divided.

DESCRIPTION Of THE HOLOTYPE INPA 19855 [conspicuous differences observed in the paratype, INPA 19856, given between brackets]: A male, snout-vent length 52.1 mm [56.2 mm], tail length 60 mm [36 mm, of which 11 mm of original tail, the remaining 25 mm regenerated], round in cross section, tapering toward the tip; limbs well developed, but relatively small in relation to the body; neck as wide as body, which is slightly depressed. All measurements are given in table 1.

Rostral hexagonal, about 2.5 times as wide as high, in contact with first supralabials, nasals and frontonasal. Frontonasal pentagonal [heptagonal], slightly wider than long, in broad contact with rostral, nasals, and prefrontals, and in narrow contact with loreal. Prefrontals pentagonal, nearly as long as wide, in contact medially, with the frontonasal anteriorly, the loreal anterolaterally, the first supraocular posterolaterally, and the frontal posteriorly; the left prefrontal in point contact with the second supraocular, separating the first supraocular and the aDifferences in count within sides of the same specimen are given as left counts/right counts.

frontal, while on the right side these four scales touch each other [both prefrontals are in short contact with the second supraocular]. Medial contact between prefrontals shorter than that with loreal [about as wide as suture with loreal]. Frontal heptagonal, 1.1–1.2 times longer than wide, slightly wider posteriorly; in broad contact with second supraoculars and in narrow contact with third supraoculars (plus a point contact with first supraocular only on the right side of the holotype); posteriorly in contact with parietal and interparietals. Frontoparietals absent. Interparietal trapezoid, wider posteriorly. Parietals longer than interparietal, each in contact with frontal, third supraocular, postocular, two temporals and two occipitals. Interparietal and parietals form an almost straight line posteriorly, where they are in contact with five subequal occipitals (medial one slightly wider [not]).

Supraoculars three; first smallest, laterally in narrow contact with loreal and in contact with first supraciliary [left side in contact with first and second supraciliaries]; second supraocular largest, laterally in contact with first, second and third [second, third and fourth] (left side) or first and second [first, second and third] (right side) supraciliaries. Three [four] supraciliaries on the left side, two [three] on the right side; on both sides first supraciliary wider anteriorly and the longest, in broad contact with loreal [first supraciliary squarish on left side; elongate and partially fused with loreal on right side]; posterior supraciliary also elongate, longer than second (when present), which is small. Nasal roughly rectangular, almost twice as long as high, divided medially by an oblique suture; in contact with rostral, frontonasal, loreal, and first and second supralabials; nostril on the lower half of the nasal suture. Loreal large, roughly pentagonal, as high as nasal, in contact with nasal, second and third supralabials, frenocular, a preocular, first supraciliary, first supraocular, prefrontal, and frontonasal. Frenocular small, quadrangular, slightly longer than high, in contact with third and fourth supralabials, anterior subocular, preocular, and loreal. It is followed posteriorly by a series of three suboculars; second longest, in contact ventrally with fourth, fifth, and sixth supralabials. A pentagonal, posteriorly pointed, postocular. Lower eyelid with a semitransparent, undivided disc. Seven supralabials, fifth below center of eye, second and sixth the highest, sixth and seventh [seventh] the longest. Five (left) or six (right) relatively large, polygonal temporals [six on both sides]. Three upper ones in contact dorsally with postocular (anterior one), parietal (the other two), and lateral occipital (posterior one). The remaining two or three temporals border the ear opening; the lowest border ventrally a small postinfralabial, which also reaches the ear-opening border. Tympanum shortly recessed.

Mental trapezoid, round anteriorly, wider than long. Postmental pentagonal, laterally in contact with first and second infralabials. Three pairs of enlarged chin shields, first and second in broad contact medially; third pair in narrow contact medially [separated by a short contact between second chin shields and pregulars]; all chin shields in contact with infralabials. Posterior chin shields in contact with three large scales, lateral and medial ones obliquely elongate, which are separated from gulars by a row of small irregularly shaped scales. Six infralabials of nearly the same length, suture between third and fourth approximately below center of eye; they are followed by two [one on the right side] smaller postinfralabials that reach the border of the ear opening. All scales on head smooth, juxtaposed, except for occipitals, which imbricate over postoccipitals.

Four roughly quadrangular, smooth, imbricate postoccipitals, slightly larger than occipitals. Posterior head scales become progressively longer than wide, grading into dorsals. Sides of neck with smooth, mostly rectangular, longer than wide, imbricate scales, in transverse rows that continues dorsally, with some extra scales in between some of the rows. Gulars in six welldefined transverse rows of rectangular (more rounded and irregular on the anterior row), imbricate, smooth scales, which become slightly larger posteriorly and wider medially. Posterior row of gulars forming a collar composed of seven scales, the medial one widest [not].

Dorsal scales imbricate, smooth, in 28/29 (because of a discontinuity on anterior rows) [29] transverse rows between interparietal and posterior level of hind limbs; anterior scales shorter, wider, roughly squared, becoming gradually longer, narrower, hexagonal, with angular to nearly round posterior margins. Toward the sides, scales become narrower and rectangular (except for small areas around arm insertion and near groin, where scales are small, flat, smooth, and juxtaposed). Ventrals smooth, slightly imbricate, in transverse rows; rectangular, only slightly longer than wide toward the midline, narrower toward the sides; lateralmost row as narrow as lateral dorsals and partially covered by them; in 20 transverse rows between collar and preanals, and 10 longitudinal rows. Thirty [31] scales around midbody. Two preanal and three femoral pores on each side, each pore surrounded by 3-4 scales (figs. 3, 4A); preanal pores separated from femoral pores by a gap, and medially by the anterior scale of the preanal plate. Preanal plate with a hexagonal, large anterior scale and five posterior scales, medial widest.

Scales on tail rectangular, smaller than dorsals, smooth, slightly imbricate; they form complete rings around the tail, with ventral scales wider than dorsals.

Scales on forelimbs large, polygonal (mostly rhomboid on upper arms), smooth, imbricate in dorsal view, distinctly smaller in anterior view, and intermediate in size in posterior view. Scales on hind limbs variably polygonal, smooth, imbricate on ventral (except for pore scales), anterior and dorsal views of thigh and on lower leg; they are largest in anterior view of thigh. Scales small, imbricate, in posterior view of thigh. Carpal and tarsal scales large, imbricate; supradigital lamellae on digits smooth, imbricate. Palmar and plantar surfaces with smooth, small granules; most infradigital lamellae divided medially, eight [seven] on finger IV and 13 on toe IV on each side. Fingers and toes clawed, with the following relative sizes: finger I <V <II <IV <III; toe I = V <II<III <IV.

COLOR PATTERN IN PRESERVATIVE: Dorsal surface of INPA 19855 dark brown with lighter spots on top of head and four (two paravertebral, two dorsolateral) tan longitudinal bands on back (with irregular margins), and flanks predominantly tan, with irregular dark-brown spots. INPA 19856 predominantly dark brown dorsally, with only an inconspicuous dorsolateral redbrown band on back; ventralmost scales on flanks predominantly tan. Limbs predominantly dark brown dorsally in both specimens. Pattern of tail similar to dorsum, but the longitudinal bands in INPA 19855 become more irregular and turn into irregular spots at some distance from the base of the tail. Ventral region cream, except for palms, soles, and tip of tail, which are grey or brown, partially mottled with cream.

DISTRIBUTION: Known only from the type locality, located a few km W of the intersection of the Rio Negro and Rio Amazonas / Solimões (fig. 5) .

ETYMOLOGY: The specific name is given after the Curupira, a mythological creature known from many regions in South America (e.g., Brazil, Argentina, Chile, Paraguay, and Uruguay). The most common versions of the legend regard the Curupira as an anthropomorphic creature of short height, with dark skin and with the feet pointed backward. The Curupira protects the forest and its inhabitants, severely punishing those who hunt for pleasure or who kill breeding females or defenseless juveniles. In the Amazonian region of Brazil the legend is vivid in the minds of people of riverside communities and the Curupira is sometimes much feared. The Curupira is also known as Curupi (in Argentina). For a comprehensive review of the Curupira legend we refer the reader to Pereira (1994).

COMPARISONS: In an attempt to properly place the new taxon among extant genera of the Gymnophthalmidae , we surveyed external morphological features of selected genera and species representing all major radiations of the family. General morphology of Marinussaurus curupira closely resembles that of Anotosaura spp. , Dryadosaura nordestina Rodrigues et al., 2005 , and to a lesser extent Colobosauroides spp. (all members of the tribe Ecpleopodini, sensu Pellegrino et al., 2001 ; Rodrigues et al., 2005). Closer resemblance is found between the new taxon and Dryadosaura . Our phylogenetic analyses partially corroborate this view, recovering the new lizard

62°W 60°W

within the Ecpleopodini radiation, although a sister relationship with Dryadosaura is not supported. Therefore, we restrict our comparisons with the Ecpleopodini and with few selected taxa of the Gymnophthalmidae that share some morphological features with the new species.

The new taxon is easily distinguished from Anotosaura by having a distinct ear opening (absent in Anotosaura ). It is distinguished from Colobosauroides by the absence of frontoparietals (present in Colobosauroides ), and by the size of the interparietal, shorter than parietals in Marinussaurus (as long as or longer than parietals in Colobosauroides ). Marinussaurus differ from Dryadosaura by the presence of three pairs of chin shields (two pairs in Dryadosaura ). The new genus also differs from Anotosaura , Colobosauroides , and Dryadosaura by having distinctive precloacal pore morphology. The precloacal pores of Marinussaurus (figs. 3 and 4A) are relatively large and arranged between three to four scales (pores relatively smaller and arranged in a single larger scale in Anotosaura , Colobosauroides [fig. 4C], and Dryadosaura [fig. 4D]).

Among the remaining ecpleopodines, Marinussaurus differs from Amapasaurus , 6 Arthrosaura , and Leposoma by the absence of frontoparietals (present in Amapasaurus , Arthrosaura , and Leposoma ), by having smooth ventrals (keeled in Amapasaurus , Arthrosaura , and Leposoma ), and smooth head scales (usually ornamented by rugosities in Amapasaurus and Leposoma ; smooth in Arthrosaura ). From Arthrosaura , it can be distinguished by the absence of a frontoparietal (present in Arthrosaura ), and by having smooth dorsal scales (keeled in Arthrosaura ). From Ecpleopus , the new genus is distinguished by the absence of frontoparietals (present in Ecpleopus ), in having smooth dorsals (keeled in Ecpleopus ) and in the presence of femoral pores in males (absent in Ecpleopus ). Kaieteurosaurus , 6 and Pantepuisaurus 6 were described based on single specimens ( Kok, 2005, 2009, respectively), which we did not examine. On the basis of the original descriptions Marinussaurus is readily distinguished from both Kaieteurosaurus and Pantepuisaurus by the absence of frontoparietals (present in Kaieteurosaurus and Pantepuisaurus ), smooth dorsals (keeled in Kaieteurosaurus and Pantepuisaurus ), rectangular smooth ventrals (hexagonal, keeled in Kaieteurosaurus and Pantepuisaurus ). A summary of diagnostic features among selected taxa within Ecpleopodini is given in table 2.

Myers and Donnelly (2001) described the genus Adercosaurus based on a single specimen, for which Castoe et al. (2004) could not associate with any subfamilies, although they suggested the genus might be related to the Alopoglossinae, Cercosaurinae , or “Ecpleopodinae” (considered here as Ecpleopodini , a tribe of Cercosaurinae ). Based on the original description of Adercosaurus , Marinussaurus curupira is distinguished from it by the absence of frontoparietals (present in Adercosaurus ), posterior margins of parietals and interparietals forming a straight line (forming a “jagged line” in Adercosaurus ), and dorsals smooth (sharply keeled in Adercosaurus ).

Body scales and general body shape of Marinussaurus is similar to some species of Ptychoglossus , but head scales immediately distinguish the two genera. Marinussaurus lacks frontoparietal scales (present in all species of Ptychoglossus ; Harris, 1994); and the interparietal is as nearly long as parietals in Ptychoglossus (visibly shorter in Marinussaurus ). Ptychoglossus is a member of the basal Alopoglossinae ( Castoe et al., 2004; Rodrigues et al., 2005) whereas Marinussaurus is a Cercosaurinae , tribe Ecpleopodini (see our phylogenetic hypothesis below).

Figures

FIG. 1. Marinussaurus curupira, in life, INPA 19856 (paratype). SVL = 56.2 mm. Photo by V.T. Carvalho.

FIG. 2. Marinussaurus curupira, INPA 19855 (holotype). Drawings of A, dorsal, B, lateral, and C, ventral views of the head. Scale bar = 5 mm.

FIG. 3. Marinussaurus curupira, INPA 19856 (paratype). Drawing of the pericloacal region showing cloacal plate, precloacal and femoral pores. Scale bar = 5 mm.

FIG. 4. Intergeneric variation of cloacal plate scales and precloacal pores: A, Marinussaurus curupira, INPA 19856; B, Arthrosaura reticulata, MPEG 19181; C, Colobosauroides cearensis, uncatalogued specimen from MPEG; D, Dryadosaura nordestina, MPEG 27738; E, Amapasaurus tetradactylus, MPEG 27370; F, Alopoglossus angulatus, MPEG 24372, a basal Gymnophthalmidae.