Taxonomy of the Threadsnakes of the tribe Epictini (Squamata: Serpentes: Leptotyphlopidae) in Colombia
Author
Pinto, Roberta Richard
Author
Passos, Paulo
Author
Portilla, José Rances Caicedo
Author
Arredondo, Juan Camilo
Author
Fernandes, Ronaldo
text
Zootaxa
2010
2724
1
28
journal article
46924
10.5281/zenodo.199951
9581ddd0-efed-4ff4-a955-4f6db2dad6c9
1175-5326
199951
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).
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).
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.