Typhlops anousius, Thomas, Richard & Hedges, Blair, 2007

Thomas, Richard & Hedges, Blair, 2007, Eleven new species of snakes of the genus Typhlops (Serpentes: Typhlopidae) from Hispaniola and Cuba, Zootaxa 1400, pp. 1-26 : 20

Typhlops anousius new species ( Fig. 8 G, 9C)

Holotype: MNHNCu 4550 (field tag number 191295), 3.5 km E Tortuguilla, Guantánamo Province, Cuba, 10 meters elevation, on 28 June 1990 by S. Blair Hedges, Richard Thomas, and Daniel McCallister.

Paratype: USNM 564783, same data as holotype.

Diagnosis: An apparently small species of Typhlops of the T. biminiensis species group distinguished from other members of the group by a lack of pigment (except for the eyes). From T. arator it can be distinguished by a relatively smaller and differently shaped rostral ( Figs. 8 , 10 A) and fewer dorsal scales (465–513 versus 578–579). The rostral of T. anousius is narrower dorsally (RW1) and at the labial border (RW3) than that of its closest relative, T. perimychus ( Fig. 10 E); RW1/RL1 = 0.74–0.77 versus 0.79–1.05 in T. perimychus . Typhlops anousius is the most extreme all the species in the width of the upper arm of the anterior nasal: ANTNAS/RW1 = 0.40–0.64 versus 0.34–0.39 in T. perimychus . In its narrow rostral T. anousius is somewhat similar to T. epactius , although its rostral is narrower (RW1/RL1, 0.74–0.77 versus 0.78–0.85) and straighter sided. Additionally, T. anousius differs from T. epactius in its lack of pigment with the latter having normally pigmented scale rows 9–11 (neck­midbody), its shorter tail (TL/TA 55–56 versus 40–48) and in being somewhat heavier bodied (TL/MBD 45–55 versus 55–58), and in having 24 scale rows (reducing at 2% TL) rather than 22 (no reduction).

Description: Snout rounded, not lobed. Rostral straight­sided in dorsal aspect (RW1/RL1 0.74–0.77), not flared on apex or at labial border; no umbo. Preocular angle 105–126°, apex rounded; lower portion contacting labials 2 and 3 of upper labial series. Anterior nasal width as a proportion of RW1 0.40–0.64. OL 1/2 height, OS 0.22–0.24. The ocular below the eye is very narrow in the holotype, but not so narrow in the paratype, a juvenile, which may not be typical, since head scale shape undergoes some ontogenetic change in Typhlops . Rostronasal pattern strongly divergent. Postocular 3–4 times higher than long. First parietal standard, spanning 2 scale rows (short on left side of USNM 564783). Second parietal present and similar in size to the first or absent. TL to 197 mm. TL/TA 55–56. TL/MBD 45–55. Middorsal scales 465–513. Scale rows 24 reducing to 22 very far anteriorly (9–12 ventral scales posterior to mental), roughly 2% TL. Coloration: completely lacking in pigment except for the eye and a few melanophores in the orbit.

Distribution: Known only from the type locality, an extremely xeric ravine along the coast ( Fig. 11 ).

Etymology: From the Greek, anousios, meaning without substance, ghostly, in reference to its lack of pigment.

Comments: The unusual lack of pigment in this species apparently is not related to its small size, in that the four specimens of T. perimychus that are smaller than the paratype of T. anousius are all pigmented. Although this species is most closely related to T. perimychus (confirmed by DNA sequence evidence; S. B. Hedges, unpublished) and the two species are separated by only 18 km ( Fig. 11 ), their degree of morphological divergence (see diagnostic traits above) suggests that they are different species, and this is further supported by their sequence divergence.

Figures

FIGURE 8. Head scalation in the Typhlops biminiensis Group, including seven new species from Cuba. (A) T. biminiensis (ASFS V 11655), from Elbow Cay, Cay Sal Bank, Bahamas. (B) T. paradoxus (ASFS V 12067), from Great Inagua, Bahamas. (C) T. epactius (ASFS V 11673), from Cayman Brac, Cayman Islands. (D) T. caymanensis (ASFS V 17112), from Grand Cayman, Cayman Islands. (E) T. perimychus (USNM 564800), holotype, from Guantanamo Bay Naval Station, Cuba. (F) T. arator (MNHNCu 191), holotype, from El Narigon, La Habana, Province, Cuba). (G) T. anousius (MNHNCu 4550), holotype, from 3.5 km E Tortuguilla, Guantánamo Province, Cuba. (H) T. notorachius (MNHNCu 4551), holotype, from 9.4 km W Imias, Guantánamo Province, Cuba. (I) T. contorhinus (MNHNCu 4552), holotype, from 4.9 km S La Tinta, Guantánamo Province, Cuba. (J) T. anchaurus (MNHNCu 4553), holotype, from within 1 km of Cueva de Agua (2.5 km airline NW Maisí), Guantánamo Province, Cuba. (K) T. satelles (SMF 61303), holotype, from Rancho Luna, about 12 km airline S Cienfuegos, Cienfuegos Province, Cuba.

FIGURE 10. Variation in measurements of Typhlops biminiensis and Cuban species of the Typhlops biminiensis Group. For all graphs (A – F), the following species are indicated by symbols: T. anchaurus (open diamond), T. anousius (closed square), T. arator (closed diamond), T. biminiensis (open circle), T. contorhinus (open triangle), T. notorachius (closed triangle), T. paradoxus (open square), T. perimychus (closed circle), T. satelles (“ X ”). Trendlines are indicated on some graphs for T. biminiensis and T. perimychus. See text for definition of abbreviations.

FIGURE 11. Geographic distribution of seven species of blindsnakes (Typhlops) in Cuba. Closed triangles = T. perimychus, closed hexagons = T. arator, open circle = T. anousius, closed circle = T. notorachius, open square = T. contorhinus, open triangle = T. anchaurus, closed square = T. satelles.