Tricheilostoma macrolepis ( Peters 1858 )

Pinto, Roberta Richard, Passos, Paulo, Portilla, José Rances Caicedo, Arredondo, Juan Camilo & Fernandes, Ronaldo, 2010, Taxonomy of the Threadsnakes of the tribe Epictini (Squamata: Serpentes: Leptotyphlopidae) in Colombia, Zootaxa 2724, pp. 1-28 : 17-19

Tricheilostoma macrolepis ( Peters 1858)

Figs. 10 , 11

Stenostoma macrolepis Peters 1858 [dated 1857], Mittheilungen. Monatsberichte der Preussischen Akademie der Wissenschaften zu Berlin, 1857:402.

Stenostoma [ Tricheilostoma ] macrolepis— Jan 1861, Archivio Per La Zoologia, L’Anatomia e La Fisiologia, Genova, 1:190– 191.

Stenostoma [ Tricheilostoma ] macrolepis— Jan & Sordelli 1861, Icnographie generale des Ophidiens, I, livr. 2: pr. V, fig. 10.

Glauconia macrolepis— Boulenger 1893, Catalogue of the Snakes in the British Museum, 1:69 (fig. 2).

Leptotyphlops macrolepis— Ruthven 1922, Miscellaneous Publications Museum of Zoology University of Michigan, 8:64.

Leptotyphlops macrolepis— Taylor 1940 [dated 1939], University of Kansas Science Bulletin, 26(15):539.

Leptotyphlops macrolepis— Dunn 1944, Caldasia, 3:51–52.

Leptotyphlops macrolepis— Bailey 1946, Occasional Papers of the Museum of Zoology University of Michigan, 492:4.

Leptotyphlops macrolepis— Dunn 1946, Caldasia, 4:122.

Leptotyphlops macrolepis— Roze 1952, Memoria de La Sociedad de Ciencias Naturales La Salle, 12:153.

Leptotyphlops macrolepis— Amaral 1954, Memórias do Instituto Butantan, 26:76.

Leptotyphlops macrolepis— Amaral 1954, Memórias do Instituto Butantan, 26:203–205.

Stenostoma macrolepis— Loveridge 1957, Bulletin of the Museum of Comparative Zoology, 117:246. Type species designation: Tricheilostoma , genus.

Leptotyphlops macrolepis— Shreve 1964, Breviora, 211:4.

Leptotyphlops ihlei Brongersma 1933 — Orejas-Miranda 1966, Comunicaciones Zoologicas del Museo de Historia Natural de Montevideo, 9:2–3.

Leptotyphlops macrolepis— Roze 1966, La Taxonomia y Zoogeografia de los Ofidios en Venezuela, 43–44.

Leptotyphlops macrolepis— Orejas-Miranda 1967, Atas do Simpósio sobre a Biota Amazonica, 5:430–432.

Leptotyphlops macrolepis— Peters & Orejas-Miranda 1970, Bulletin of the United States National Museum, 297:170.

Leptotyphlops macrolepis— Hoogmoed 1977, Zoologische Mededelingen, Leiden, 51:110–11.

Leptotyphlops macrolepis— Hahn 1979, Catalogue of American Amphibians and Reptiles, 230:3.

Leptotyphlops macrolepis— Gasc & Rodrigues 1980, Bulletin du Museum d'Histoire Naturelle de Paris, 2:567.

Leptotyphlops macrolepis— Hahn 1980, Das Tierreich, 101:20.

Leptotyphlops macrolepis— Lancini 1986, Serpientes de Venezuela:170–171.

Leptotyphlops macrolepis— Perez-Santos & Moreno 1988, Museo Regionale di Scienze Nataturali, Torino, 6:420.

Leptotyphlops macrolepis— Starace 1998, Guide des serpents et amphisbènes de Guyane, 77.

Leptotyphlops macrolepis— McDiarmid, Campbell & Touré 1999, Snake Species of the World, 1:35.

Stenostoma macrolepis— Bauer, Wallach and Günther 2002, Mitteilungen aus dem Hamburgischen Zoologischen Museum und Institut, 78:160.

Leptotyphlops macrolepis Passos, Caramaschi & Pinto 2005 , Boletim do Museu Nacional, Nova Série, Zoologia, 520:5.

Leptotyphlops macrolepis— Passos, Caramaschi & Pinto 2006, Amphibia-Reptilia, 27:349.

Tricheilostoma macrolepis— Hedges, Adalsteinsson & Branch in Adalsteisson et al. 2009, Zootaxa, 2244:11.

Lectotype: ZMB 1434 ( Fig. 10 ), from Puerto Cabello (10° 25' N, 068° 10' W, sea level), state of Carabobo, Venezuela.

Paralectotypes: ZMB 5294, from Puerto Cabello, state of Carabobo, Venezuela; ZMB 5722, from “S. Amerika ” (= South America).

Diagnosis. Tricheilostoma macrolepis is distinguished from all congeners by the following combination of characters: snout truncate in dorsal and ventral view, rounded in lateral view; supraocular present; ocular subhexagonal with rounded shape at the eye level; enlarged eyes occuping most ocular width; rostral subtriangular in dorsal view not reaching ocular level; frontal longer than other midsaggital head scales; temporal distict; three supralabials (2+1); four infralabials; 211–243 middorsal scales in females and 218–243 in males; 217–225 midventral scales in females and 204–221 in males; 18–24 subcaudal scales in males and 16–21 in females; fused caudals present; 10 scales around the middle of tail; dorsum uniformly dark brown to black on seven dorsal scale rows, contrasting with the pale brown to brown covering the centre of scales on the seven lateroventral rows.

Colour of the lectotype in preservative: Seven dorsal scale rows uniformly dark brown and seven lateroventral scale rows brown on center of each scale, with beige border marking the limit of scales; colour of head and lower margins of scales follows body pattern; cloacal shield and terminal spine dark brown.

Colour in life: Similar, but more intense to colour pattern in preservative ( Fig. 11 ).

Sexual dimorphism: Males have more subcaudal scales than females (F(1,12) = 8.0; p <0.01). No sexual dimorphism were found in middorsal scales (F(1, 12) = 0.7; p = 0.4) and in midventral scales (F(1, 5) = 2.2, p = 0.2).

Variation: Middorsal scales 211–243 (x¯ = 225.8 ± 12.2, n = 5) in females and 218–243 (x¯ = 230.3 ± 8.8, n = 9) in males; midventral scales 217–225 (n = 2) in females and 204–221 (x¯ = 212.2 ± 7.4, n = 5) in males; subcaudal scales 18–24 in males (x¯ = 21.8 ± 2.1, n = 9) and 16–21 (x¯ = 18.6 ± 1.8, n = 5) in females; TL 126–322 mm (x¯ = 226.2 ± 85.9, n = 5) in females and 126–297 mm (x¯ = 217.6 ± 60.0, n = 9) in males; TL/TAL ratio 10.5–14.9 (x¯ = 12.1 ± 1.6, n = 9) in males and 12.4–15.8 (x¯ = 13.9 ± 1.7, n = 5) in females; TAL 6.7–9.5% of TL in males (x¯ = 8.4 ± 0.0, n = 9) and 6.3–8.1% in females (x¯ = 7.3 ± 0.0, n = 5); TL/MB ratio 40.9–65.6 (x¯ = 49.0 ± 9.8, n = 5) in males and 40.7–52.5 (x¯ = 47.7 ± 6.2, n = 3) in females; TAL/MT ratio 5.2–6.2 (x¯ = 5.5 ± 0.4, n = 4) in males and 3.8–5.3 (n = 2) in females; relative eye diameter 1.4–2.0 (x¯ = 1.7 ± 0.3, n = 3) in males and 1.4–1.9 (n = 2) in females; rostral width 0.4 (x¯ = 0.4 ± 0.0, n = 4) in males and 0.3–0.4 (n = 2) in females.

Distribution. In Colombia, Tricheilostoma macrolepis has a trans-Andean pattern of distribution, occurring along the three Cordilleras and also on Pacific to Amazon lowlands ( Fig. 3 ).

Remarks. We must address a taxonomic issue relevant to the leptotyphlopids. Loveridge (1957) assigned Stenostoma macrolepis as the type species of the Tricheilostoma Jan , but, as pointed out by McDiarmid et al. (1999), he overlooked the first use of the name Tricheilostoma in a figure legend of Jan (in Jan and Sordelli, 1860), in association with the African species Stenostoma (Tricheilostoma) bicolor and Stenostoma (Tricheilostoma) gracile , later species placed as synonym of Glauconia bicolor (= Tricheilostoma bicolor ) by Boulenger (1893). Adalsteinsson et al. (2009) followed Loveridge (1957) and revalidate Tricheilostoma referring to macrolepis group and described the genus Guinea to the bicolor group. Despite the overlooked designation of Stenostoma macrolepis to Tricheilostoma type species by Loveridge (1957), the ICZN (1999, Art. 70.2, p. 74) indicates that if it is found that an earlier type species has been overlooked, the overlooked fixation is to be accepted and later fixations are invalid. Based on these arguments, we maintain the Loveridge (1957) type species designation.

Figures

FIGURE 3. Geographic distribution of species of the tribe Epictini in Colombia. Type localities correspond to white symbols.

FIGURE 10. Dorsal (A) and ventral (B) views of body and dorsal (C), lateral (D), and ventral (E) views of head of the lectotype of Tricheilostoma macrolepis (ZMB 1434).

FIGURE 11. Dorsal (A) and lateral (B) views of the Tricheilostoma macrolepis (MHUA 14509) in life from Capitan, Briceño, departament of Antioquia.