Leptotyphlops nigroterminus, Published, 2007

Published, First, 2007, A revision of the genus Leptotyphlops in northeastern Africa and southwestern Arabia (Serpentes: Leptotyphlopidae), Zootaxa 1408, pp. 1-78 : 40-42

Leptotyphlops nigroterminus sp. nov. ( Plate 12 , Fig. 1)

Black-tip worm snake

Glauconia signata — Sternfeld, 1910: 13 (part, Tabora).

Leptotyphlops conjuncta — Vesey-FitzGerald, 1958: 35.

Leptotyphlops scutifrons — Spawls et al., 2002: 299 (part).

Holotype. MCZ 54813, a male from Karema , eastern shore of Lake Tanganyika, Mpanda District, Rukwa Region, Tanzania (06°50’S, 30°50’E, elevation 950 m), collected by C.J.P. Ionides, 7 July 1956.

Allotype. MCZ 52634, a female from Manyoni , Manyoni District, Singida Region, Tanzania (05°43’S, 34°50’E, elevation 1270 m), collected by C.J.P. Ionides, 24 August 1951.

Paratypes. MCZ 54653 — Kipangate , Rukwa Valley, Tanzania, collected by D. Vesey-FitzGerald, February 1955 ; NMK /O.420 — Mpanda , Mpanda District, Rukwa Region, Tanzania (07°57’S, 32°25’E), collected by Ortlepp, May 1959 ; KU 172930 — a female from Mara Serema Lodge , Masai Mara Reserve, Narok District, Kenya (01°23’S, 35°00’E, 1585 m), collected by W.E. Duellman, 18 August 1976 ; ZMB 51610* — Tabora, Tabora District, Tabora Region, Tanzania, collected by Wintgens ; CAS 227733 — Msago Shamba , Mpanda District, Tanzania (07°06' S, 31°09'), collected by T. A. Gardner, 14 April 2003 .

Diagnosis. Apart from its distinctive skull, with a rhombic postparietal bone and paired parietals ( Plate 4 , Fig. 2A), this unique form differs from all other African species in its light brown colouration with the distal portion of the tail black.

Etymology. The specific name is derived from the diagnostic black tail tip; from the Latin niger = black and terminus = tip.

Description (paratype variations in parentheses). Body cylindrical, with head and neck broadened and flattened, the short tail tapers slightly to a small terminal spine.

Snout rounded, rostral broad (0.53–0.67 head width, mean = 0.59), fused with the frontal, unguiform, extending well beyond the level of the eyes, a preoral groove present ventrally. Behind rostral, upper lip bordered by infranasal (nostril midway between rostral and supralabial along nasal suture), small anterior supralabial with width along lip twice that of infranasal, large but narrow ocular, and tall posterior supralabial. Supraoculars pentagonal, anteriorly wedged in between supranasal and ocular, posteriorly in straight contact with the hexagonal postfrontal, which is subequal in size to the supraoculars, interparietal and interoccipital. Parietals oblique and in contact with the posterior supralabials. Occipitals not fused (fused in all 5 paratypes). Temporal single. No mental, four infralabials.

Body covered with 14 rows of smooth, imbricate, subequal scales. Reduction to 12 rows on the tail takes place lateral to the subtriangular cloacal shield, which is entire (tail rows 12 in the allotype, 10 in the four paratypes). Total middorsals 236 (228 in other male, 260–300 in females); subcaudals 23 (27 in other male; 25–27 in females).

Total length 159 mm, tail 12 mm; midbody diameter 3.5mm.

Total length/diameter ratio 45 (46–84); total length/tail ratio 13.2 (11.7–14.8).

Middorsal seven scale rows medium brown, rostral and dorsal tail blackish-brown, paler brown ventrally, distal half of tail with black ring (in the smallest specimen of 82 mm total length only the extreme tip of the tail is black, in the other paratypes the distal third of tail has black ring).

Size. Largest specimen ( MCZ 52634 — Manyoni , Tanzania) 180 + 13 = 193 mm .

Habitat. The habitat in western Tanzania is miombo woodland, but in the Masai Mara Reserve in Kenya the vegetation is a mosaic of evergreen bushland and secondary Acacia wooded grassland (White, 1983).

Distribution. Southwestern Kenya and western Tanzania, 1000–1600 m ( Plate 11 ).

Figures

PLATE 4. Figure 1. Dorsal views of the skulls of Leptotyphlops. A. Leptotyphlops nigricans (MCZ 21473) and B. Leptotyphlops kafubi (FMNH 56374), both after List (1966). KEY to bone abbreviations from List, 1966: Ax = axis, At = atlas, Eo = exoccipital, F = frontal, M = maxilla, N = nasal, P = parietal, Pf = prefrontal, Po = prootic, So = supraoccipital. C. Leptotyphlops cairi, after Abdeen et al. (1991). KEY to bone abbreviations from Abdeen et al., 1991: B.OC. = basioccipital; B.SP. = basisphenoid; C.T.C. = cartilaginouis trebacula cranii; EX.OC. = exoccipital; FR. = frontal; L.P.P.MX. = lateral process of maxilla; MX. = maxilla; NA. = nasal; OC.CO. = occipital condyle; P.MX. = premaxilla; P.OT. = prootic; P.VO. = prevomer; PA. = palatine; PR. = parietal; PR.FR. = prefrontal; PR.L.DG. = lateral downgrowth of parietal; PT. = pterygoid; S.OC. = supraoccipital. The lines represent 1 mm to scale. The stipple indicates thin transparent membrane. Figure 2. Dorsal views of the skulls of Leptotyphlops. A. Leptotyphlops nigroterminus sp. nov. (ZMB 51610); B. Leptotyphlops macrurus (BMNH 1957.1.10.26); C. Leptotyphlops boulengeri (MCZ 40087); D. Leptotyphlops reticulatus (BMNH 1954.1.12.77). E. Leptotyphlops longicaudus (NMZB-UM 29371); F. Leptotyphlops blanfordii (BMNH 1977.833); G. Leptotyphlops nursii (FMNH 66158). H. Leptotyphlops scutifrons merkeri (NMZB 8089). The lines represent 1 mm to scale. KEY: f = frontal; n = nasal; p = parietal; pp = postparietal; so = supraoccipital.

PLATE 11. Leptotyphlops. Distribution of the Leptotyphlops scutifrons species group in East Africa. Type localities are labelled.

PLATE 12. Figure 1. Leptotyphlops nigroterminus sp. nov. Dorsal and lateral views of the head of the holotype, MCZ 54813 — Karema, Tanzania. The line represents 1 mm to scale. Figure 2. Leptotyphlops latirostris. Dorsal, lateral and ventral views of the head of MCZ 53261/57459 from Uvira, DDC. Drawings by J. Boundy. The line represents 1 mm to scale. Figure 3. Leptotyphlops scutifrons merkeri. Dorsal, lateral and ventral views of the head of the syntype, MCZ 31627 — Moshi, Tanzania. Drawings by J. Boundy. The line represents 1 mm to scale. Figure 4. Dorsal views of the heads of: A. Leptotyphlops latirostris. MRAC 18014 (Uvira, Kivu), compared with B. Leptotyphlops scutifrons pitmani. MRAC 18006 (Rwankuba, Rwanda), after Laurent (1956). The lines represent 1 mm to scale.