A new species of Phyllodactylus (Reptilia, Squamata, Gekkonoidea, Phyllodactylidae) from Isla de Guanaja in the Honduran Bay Islands
Author
Mccranie, James R.
Author
Hedges, S. Blair
text
Zootaxa
2013
3694
1
51
58
journal article
10.11646/zootaxa.3694.1.3
96e7bfe1-2aa9-44da-b594-4494d491e2ec
1175-5326
284310
9C6AF91A-562E-48A3-BD24-BB506462BBE3
Phyllodactylus paralepis
sp. nov.
(
Fig. 2
,
3
)
Phyllodactylus palmeus
Dixon, 1968:419
(part).
Phyllodactylus insularis
Echternacht, 1968:151
.
Phyllodactylus palmeus
Wilson & Hahn, 1973:104
(part).
Phyllodactylus palmeus
McCranie
et al.,
2005:78
(part).
Holotype
.
FMNH 283552 (genetic sample 1, Genbank accession
KF245415
), an adult male from Savannah Bight, 16.29078°, -85.50300°,
Isla
de Guanaja, Islas de la Bahía,
Honduras
,
15 m
elevation, collected
20 September 2012
by James R. McCranie & Leonardo Valdés Orellana.
Paratypes
(7).
FMNH 283553, adult female from East End, 16.486°, -85.832°,
Isla
de Guanaja, near sea level, collected
19 September 2012
by James R. McCranie & Leonardo Valdés Orellana; USNM 580288 (genetic sample 2, Genbank accession
KF245416
), 580289, adult males, 580290, an adult female, East End,
Isla
de Guanaja, collected
16 November 2011
by James R. McCranie; FMNH 283554, an adult female from Hotel Posada del Sol ruins,
Isla
de Guanaja, 16.462117°, -85.853867°, near sea level, collected
21 September 2012
by James R. McCranie and Leonardo Valdés Orellana; USNM 565401, an adult female from East Bight,
Isla
de Guanaja, collected
9 May 2007
by Alexander Gutsche & James R. McCranie; KU
101377
, an adult male,
Isla
de Guanaja, no other data,
30 m
, collected on
10 July 1996
by A. C. Echternacht.
Referred specimens.
See Appendix I.
Geographic distribution.
Phyllodactylus paralepis
is known to occur only at low elevations on
Isla
de Guanaja in the Islas de la Bahía,
Honduras
(
Fig. 4
).
Diagnosis.
Phyllodactylus paralepis
has more closely spaced (0–1 granules separating) tubercles (
Fig. 3
) on the dorsal surfaces than does
P. palmeus
(1–3 granules separating dorsal tubercles). In addition,
P. paralepis
has 41–53 tubercles in the paravertebral row from the rear of the head to the tail and 16–17 dorsal tubercle rows across the midbody (versus 35–43 tubercles from head to tail and 11–15 tubercle rows across midbody in
P. palmeus
). Those two species also differ from each other in amount of sequence divergence (2.9 %;
Fig. 1
).
Phyllodactylus paralepis
also differs significantly in sequence divergence (9.8 %) from the remaining species of
Phyllodactylus
occurring in
Honduras
(
P. tuberculosus
). Morphologically,
P. paralepis
differs from
P. tuberculosus
, which occurs in southern
Honduras
, in having 41–53 tubercles in the paravertebral row from the rear of the head to the tail and 29–36 tubercles in the paravertebral row between the levels of the axilla and groin (versus 26–32 tubercles from head to tail and 20–24 tubercles between axilla and groin in
P. tuberculosus
). Dixon (1960) described
P. insularis
from Half Moon Cay in
Belize
about
230 km
W of
Isla
de Guanaja. According to Dixon (1960),
P. insularis
has a distinct white subocular spot and dark brown dorsal surfaces, and lacks enlarged tubercles on the dorsal surfaces of the thighs (versus white subocular spot absent, pale brown dorsal surfaces, and enlarged tubercles present on thighs in
P. paralepis
).
Description of
holotype
.
Rostral ca. two-thirds as high as wide, its dorsal edge with slight posterior inward curve, and with a median groove about half length of rostral; internasals paired, somewhat rectangular, in broad contact medially, bordered posteriorly by six granules and postnasal of each side; nostril surrounded by rostral, first supralabial, internasal, and two postnasals; shallow internasal and frontal depressions present; 16 scales present between nostril and eye (loreals); scales in medial loreal region ca. three times larger than interorbital scales; 22 scales across snout between third supralabials; 16 scales between anterior edges of orbits and 24 midorbital scales; eye large, its diameter contained in snout length slightly less than two times; pupil vertically elliptical, with reticulated edges; eyelid with one row of granules and one larger outer row of scales, ultimate 4–5 pointed; diameter of ear contained in eye diameter ca. five times; ear opening vertically subtriangular, not denticulate, scales on anterior and posterior edges rounded, subequal in size; rear of head with many large tubercles intermixed with granular scales; six supralabials and infralabials to point below center of eye; mental bell-shaped, slightly longer than wide, bordered posteriorly by two postmentals; postmentals much longer than wide, their median edges in broad contact with one another; postmentals bordered posteriorly by eight smaller scales; postmentals contacting only first infralabial on each side.
Dorsum with 16 transverse (across body) rows of enlarged, keeled tubercles at midbody, paravertebral row with 49 tubercles from rear of head to base of tail, 30 between levels of axilla to groin; paravertebral rows separated from each other by 0–1 rows of granules; four rows of tubercles reach to rear of head on right side, three on left side; six rows of tubercles across base of tail; 3–3 enlarged preanal scales present; venter with 60 longitudinal and 27 transverse scale rows.
Dorsal surface of upper arm with flattened scales, forearm with scattered tubercles dispersed among smaller flattened scales; dorsal surface of thigh with 4–5 larger tubercles among smaller scales; lower hind limb with 12– 14 tubercles dispersed among smaller scales; fourth finger lamellae 9–10, that of fourth toe 12–12; claw hidden when viewed from below; terminal pad large, paired pad scales longer than wide, truncated.
Measurements in mm: snout-vent length 60.1; axilla-groin length 27.9; forelimb length 15.5; hind limb length 24.1; tail length 69; head length 15.6; head depth 6.8; head width (midorbital) 9.2; eye diameter 3.9; ear longitudinal diameter 0.8; snout length 6.3; eye-ear length 5.4.
FIGURE 2.
Adult male holotype (FMNH 283552; SVL 60.1 mm) of
Phyllodactylus paralepis
sp. nov
.
in life. Photograph by J.R. McCranie.
FIGURE 3.
Comparison of spacing of enlarged dorsal tubercles between A)
Phyllodactylus paralepis
sp. nov.
(FMNH 283552) and B)
P. palmeus
(KU 203123). Photographs by J.R. McCranie.
Color in life (
Fig. 2
): dorsum pale greenish brown with Sepia (219) mottling and Mikado Brown (121C) tubercles; top and lateral surfaces of head similar to that of body, except Sepia pigment forming longitudinal lines on snout and supralabials; dorsal surface of tail brown with Sepia crossbands; dorsal surfaces of limbs pale brown with Sepia and Raw Umber (123) mottling and crossbands; chin, throat, and belly pale brown with Raw Umber mottling on anterior half of belly and Sepia mottling and blotches on posterior half of belly; ventral surfaces of limbs pale brown, except soles and palms pinkish brown; digital pads dirty white to white; iris golden brown.
Color in alcohol: dorsal ground color pale tan with narrow dark brown, incomplete medially, reticulated crossbands; dorsal surfaces of limbs pale tan with dark brown reticulated crossbands; top of head pale brown with reticulated dark brown lines; side of head with dark brown postnasal and postorbital lines; tail tannish brown with narrow reticulated dark brown crosslines; supralabials cream with small dark brown spots on those anterior to eye; ventral surfaces of head and body nearly immaculate cream; venter of limbs nearly immaculate cream, except that posterior ventrolateral edges mottled with dark brown; palms, soles, and digits tan; subcaudal surface cream with dark brown mottling on anterior third, becoming crossbanded with dark brown on tan ground color on distal half.
Variation.
Snout-vent length of the
type
series ranges from 55.6–70.4 (60.8 ± 6.7) in males, 60.1–63.3 (61.8 ± 1.5) in females; postmentals number two in all, with postmentals contacting only first infralabial on each side in all; midorbital scales 20–25 (22.9 ± 1.6); scales across snout between third supralabials 20–29 (25.1 ± 3.1); longitudinal and transverse ventral scales 53–61 (57.6 ± 3.4) and 25–28 (26.9 ± 1.0), respectively; scales bordering postmentals 4–8 (6.3 ± 1.4); scales bordering posterior edge of internasals 5–8 (6.5 ± 0.9); scales between nostril and eye (loreals) 12–16 (14.3 ± 1.6); fourth toe lamellae 12–14 (12.6 ± 0.7); fourth finger lamellae 9–12 (10.6 ± 1.0); tubercles in paravertebral row from rear of head to base of tail and between axilla–groin 41–53 (47.3 ± 3.7) and 29–36 (31.4 ± 2.3), respectively; tuberculate rows across base of tail 6–8 (7.0 ± 1.1); supralabials and infralabials six in all but one with eight.
The
paratypes
have a somewhat more muted dorsal pattern in alcohol than does the
holotype
that consists of scattered dark brown spotting and mottling, otherwise they are similar in color to that described above for the
holotype
. A juvenile referred specimen (FMNH 283555; SVL
27.1 mm
) is very similar in color in alcohol to that of the
holotype
, except that the dark dorsal crossbands on the anterior third of the body are solid, thus more distinct than in the
holotype
. The photographs of
Phyllodactylus paralepis
in Köhler (2000, 2003, 2008; all as
P. palmeus
) show a dorsal pattern similar to that seen in the
holotype
(
Fig. 2
).
Habitat.
Phyllodactylus paralepis
is a nocturnal gecko that before the invasion of
Hemidactylus
species was common on the walls of buildings in Savannah Bight. Those
Hemidactylus
species appear to have replaced
P. paralepis
in edificarian situations in recent years. However,
P. paralepis
remains common in non-edificarian situations on Guanaja. Other places of nocturnal activity include in walls of caves and on coconut and thorn palms. Its diurnal hiding places include termite nests, beneath tree bark, and especially within the bases of palm fronds and associated coverings. It can also be seen inside coconut palm debris lying on the ground and occasionally in Sea Grape (
Cocoloba uvifera
) leaf litter. Echternacht (1968: 151) reported finding one under “loose palm bark about
1.5 m
above ground.”
Phyllodactylus paralepis
occurs sympatrically with two other native gekkotan species,
Sphaerodactylus alphus
McCranie & Hedges
and
S. guanajae
McCranie & Hedges. See Conservation
status for comments on co-occurrence with recently introduced gecko species.
FIGURE 4.
Map of Honduras showing localities for specimens examined of
Phyllodactylus paralepis
sp. nov
.
(squares) and
P. palmeus
(circles).
Conservation status.
Two species of
Hemidactylus
,
H. frenatus
Schlegel
and
H. mabouia
(Moreau de Jonnès) have been introduced to
Isla
de Guanaja in recent years.
Hemidactylus mabouia
was abundant on the walls of a hotel in Savannah Bight during 2007 (Gutsche & McCranie 2009), but that species has now apparently been displaced by the more aggressive
H. frenatus
(JRM personal observations).
Hemidactylus frenatus
was first introduced on the
Honduran
Bay Islands on the island of Utila (Köhler 2001).
Phyllodactylus palmeus
was formally a common species on
Isla
de Utila, but has now been completely eradicated in edificarian situations on Utila by
H. frenatus
. To make matters worse,
H. frenatus
has successfully invaded non-edificarian situations on Utila, where during
September 2012
it was a more commonly found species in forested areas along the east coast than was
P. palmeus
. As
H. frenatus
populations on Utila apparently have at least a seven year head start on that island compared to the populations of
Hemidactylus
on Guanaja, it can be expected that
H. frenatus
will likewise invade the similar non-edificarian situations on Guanaja and begin the process of displacing
P. paralepis
there as well.
The introduced
Hemidactylus mabouia
population on the island of
Curaçao
has been noted to have displaced the native
Phyllodactylus martini
van Lith de Jeude in houses on that island (van Buurt 2005). Apparently, island populations of
Phyllodactylus
are generally more vulnerable to displacement by invasive species of
Hemidactylus
.
Etymology.
The specific epithet
paralepis
is formed from the Greek
para
(near) and
lepis
(scale) and refers to the closely spaced tuberculate dorsal scales in this Guanaja Island endemic.