Echinosaura centralis, DUNN, 1944

ECHINOSAURA CENTRALIS DUNN, 1944 View in CoL

( FIGS 6B, 7, 10B, 11, 12)

Echinosaura centralis Dunn, 1944: 397–398 View in CoL (original description). Types destroyed or lost (see below), from ‘ Muzo ( Humbo ) [Boyacá department, Colombia]’ and ‘ Robledo (near Medellin) [Antioquia department, Colombia]’, exact localities are unknown .

Echinosaura horrida palmeri ( Boulenger, 1911) View in CoL – Uzzell, 1965: 85 (for ILS 216–218 from ‘Muzo’ and CNHM 63813 from ‘ 4 km northeast of Bellavista, on the Río Porce, in Antioquia’).

Designation of neotype: Dunn (1944) described Echinosaura centralis View in CoL based on eight specimens, seven of which were collected in Muzo, department of Boyacá, Colombia and deposited in the collection of Museo de La Salle (Bogotá, Colombia, MLS). The remaining specimen was collected in Robledo, M e d e l l í n, d e p a r t m e n t o f A n t i o q u i a, C o l o m b i a and deposited in the collection of Colegio San José (Medellín, Colombia, now Museo de Ciencias Naturales de La Salle, CSJ). However, Dunn did not provide an individual identification for each specimen beyond mentioning that the holotype was the largest specimen from Muzo. According to Uzzell (1965: 85), Hno. Nicéforo María informed him ‘the specimens in the Instituto de La Salle, including the holotype and 6 of the 7 paratypes, have been destroyed’. Details were not given, but those specimens were probably destroyed during the fire of the institute (MLS) in 1948. Therefore, Uzzell based the synonymization of E. centralis View in CoL with E. h. palmeri View in CoL (currently E. palmeri View in CoL ) on examination of three topotypic specimens from Muzo [ILS (=MLS) 216–218] and one specimen from ‘ 4 km northeast of Bella Vista, on the Río Porce, in Antioquia’ (CNHM 63813), and according to him near the ‘type-localities’. We visited both Museo de La Salle (Bogotá) and Museo de Ciencias Naturales de La Salle (Medellín), but had no success in locating the remaining type specimen and no record in the museum database suggests its existence. We also noticed that ‘topotypic’ specimens from Muzo municipality mentioned by Uzzell (1965), are actually from Otanche municipality (based on the original specimen tags). Given the absence of type material of E. centralis View in CoL , and in accordance with the ICZN (1999) Art. 75, we designate a neotype for this species. We considered this specimen the best candidate because: (1) there is enough evidence to identify it as the same entity described by Dunn (1944), (2) it is an adult male in excellent preservation condition, (3) there is a photograph in life and (4) it could be included in our phylogeny. A description of the neotype is given below.

Neotype (designated here): MHUA-R 13332 , an adult male ( Figs 11, 12). Colombia, department of Antioquia, municipality of San Rafael, embalse Jaguas, Caño Girón (6° 23’ 54.672’ N, 75° 01’ 37.092’ W, 1275 m a.s.l.). Collected on 23 August 2017 by Juan D. Vásquez-Restrepo.

Description of neotype: Adult male ( Figs 11, 12), SVL = 60 mm, TRL = 27 mm, SL = 5.7 mm; HL = 15.2 mm, HW = 9.1 mm, TaL = 10.2 mm. Rostral scale single. Internasals two, longer than wide, with three longitudinal stretch marks, in contact with rostral anteriorly, nasals laterally, frontonasals posteriorly. Nasals subtriangular, in contact with internasals and first supralabials. Frontonasals about three times longer than wide, rectangular, with the posterior edges forming an obtuse angle and a depressed area in the middle part of each scale. Frontal single, wider anteriorly and thinner posteriorly, with a series of longitudinal, barely visible longitudinal ridges. Supraoculars three, first supraocular in contact with frontal and frontonasals, smaller than second and third; third supraocular in contact with three small, keeled ciliaries. Lower eyelid with a palpebral disc divided into three large, unpigmented scales. A large polygonal scale in loreal region not in contact with the supralabials, except on the right side where it is fused with the first large subocular scale. Loreal in contact with preciliary, frontonasal and nasal. Suboculars in four small rows, in contact with a fifth row formed by five large scales on the left side and four on the right side (fifth scale fused with loreal), which are in contact with second to fifth supralabials. Frontoparietals paired, small, well defined. Parietal region covered with small irregular scales. Five upper and four lower labials on both sides. Mental posteriorly in contact with postmental. Postmental trapezoidal, in contact with first infralabial and anterior half of second infralabial. Chin shields large, in one pair, about three times longer than wide, in contact with posterior half of the second and anterior half of the third infralabials, separated from infralabials by three rows of small, hexagonal scales arranged longitudinally, larger than adjacent. Gular region with small, semicircular and tubercular scales, becoming spine-like scales that extend to posterior part of head in dorsal view in four longitudinal rows. Two of these lines are continuous and parallel, extending on paravertebral region and separated from each other by 6–7 irregular, small scales. The remaining two rows extend on upper coastal region, also formed by spine-like scales, but forming a discontinuous longitudinal and sinuous line. On the sides, there is a series of spine-like scales forming oblique lines. Spine-like scales on dorsum separated from each other by small, irregular or tubercular scales. Limbs pentadactyl, digits clawed. Subdigital lamellae on the fourth finger 15/14 (second one on left side divided); subdigital lamellae on the fourth toe 21. Scales on pectoral region flat, rounded, becoming six rows of squared and keeled scales on the belly. Tail with two parallel ridges dorsally, formed by a series of increasing in size scales from the anterior margin of each caudal segment, with more-developed scales forming longitudinal ridges laterally. Tail complete, with three subcaudal scales per caudal segment.

Dorsum light brown, with some dark-brown scales on head, barely yellowish blotches on body and limbs, and two cream spots at the base of the tail. Scales of ventral surface of head dark brown (almost black), most of them with a cream spot on the centre. Mental and labials with whitish colouration on the posterior edges. Suture between postmental and chin shields with a white transverse stripe. Scales on belly with an irregular pattern of chessboard (black and cream scales). Ventral surface of tail dark brown (almost black) from the basis, except by a few whitish scales on the anterior and posterior part.

Diagnosis: The following data are based on 70 examined specimens (referred material listed in Supporting Information, Appendix SII). Echinosaura centralis possesses the following characteristics: (1) snout pointed; (2) internasal divided longitudinally (rarely single); (3) frontonasals paired; (4) frontal single and long (it extends up to the middle of the eyes); (5) frontoparietals paired; (6) supraoculars two or three, large; (7) supralabials 4–6 (usually five); (8) infralabials 3–5 (usually four); (9) postmental single; (10) large chin shields in one pair; (11) two paravertebral ridges, separated from each other by usually five or more small, irregular scales; (12) spine-like scales forming oblique lines on lateral surface of body; (13) ventral scales squared, usually keeled; (14) subdigital lamellae on the fourth finger 12–18; (15) subdigital lamellae on the fourth toe 20–27; (16) femoral pores per hind limb in males 4–9; (17) dorsal surface of tail with two parallel ridges, formed by a series of increasing in size scales from the anterior margin of each caudal segment; lateral surface of tail with more-developed scales forming longitudinal ridges (coded as ‘= pattern’); (18) subcaudals per caudal segment three (when tail is not regenerated); (19) dorsum brown or dark brown, relatively uniform, sometimes with yellowish marks and/or two spots more or less distinguishable at the base of tail; ventral surface of head and neck mainly light brown, except on the anterior part where there is a darker ground colour with some transverse cream blotches, extending to labial scales; ventral surface of body (including limbs) mainly light brown spotted with dark brown or cream, while that of tail almost completely dark. Colouration in preservative is darker in some specimens.

Combination of these characteristics distinguishes Echinosaura centralis from its congeners. In addition, the distinctiveness of E. centralis and its sister-species E. palmeri ( Fig. 2) is corroborated by uncorrected pairwise distances of 17.6% in ND4 and 5.6% in 16S ( Table 1).

Geographic distribution: Echinosaura centralis is endemic to Colombia. It occurs in the Cordillera Central from Tolima to Bolívar departments, the adjacent Magdalena Valley and the west versant of the Cordillera Oriental in Cundinamarca and Boyacá departments. Most records are above 1000 m a.s.l., but its elevation ranges from 50 to 2200 m a.s.l. ( Fig. 8) .

Natural history: We have observed individuals of Echinosaura centralis diving into the streams and swimming short distances after being disturbed.

Variation: The referred specimens are similar to the neotype with the following noteworthy exception: internasal scale single (an unusual condition) in MHUA-R 10132 , 11245 , 11440 , 12111 , 12273 and 13212 .