Pseudogekko atiorum, Davis, Drew R., Watters, Jessa L., Köhler, Gunther, Whitsett, Collin, Huron, Nicholas A., Brown, Rafe M., Diesmos, Arvin C. & Siler, Cameron D., 2015

Davis, Drew R., Watters, Jessa L., Köhler, Gunther, Whitsett, Collin, Huron, Nicholas A., Brown, Rafe M., Diesmos, Arvin C. & Siler, Cameron D., 2015, Redescription of the rare Philippine false gecko Pseudogekko brevipes (Reptilia: Squamata: Gekkonidae) and description of a new species, Zootaxa 4020 (2), pp. 357-374 : 363-371

Pseudogekko atiorum sp. nov.

( Figs. 1 , 3–6 )

Holotype. PNM 9518 ( CDS Field No. 954, formerly KU 302818), adult female, collected at 22:00 h on 21 February 2005, on Mt. Talinis, Barangay Bongbong, Municipality of Valencia, Negros Oriental Province, Negros Island, Philippines (N: 9.26000°, E: 123.20327°; WGS 84; 1100 m elev.), by CDS.

Paratypes. Two adult females (CAS-SUR 19372, 21122) collected from Municipality of Cauayan, Negros Occidental Province, Negros Island, Philippines by A.C. Alcala and Q. Alcala. One adult female ( CAS 138097) collected by Q. Alcala and two adult males ( CAS 145793, 147491) collected by Q. Alcala and M. Pinero, respectively, from Municipality of Pamplona, Negros Oriental Province, Negros Island, Philippines. One adult female ( CAS 134269) collected by A.C. Alcala and one adult male (CAS-SUR 26778) collected by D. Empeso from Municipality of Siaton, Negros Oriental Province, Negros Island, Philippines. Four adult males ( CAS 128956, 128959, 128963, 128971) collected from the Municipality of Sibulan, Negros Oriental Province, Negros Island, Philippines by L.C. Alcala. Two adult females ( CAS 134292, TNHC 62478) collected by A.C Alcala and RMB, respectively, and one juvenile female (KU 327770) collected by RMB from Municipality of Valencia, Barangay Bongbong, Negros Oriental Province, Negros Island, Philippines. One adult male ( CAS 145710) collected from Municipality of San Juan, Siquijor Province, Negros Island, Philippines by L.C. Alcala.

Other Referred Specimens. Five specimens ( CAS 89812, 147523, CAS-SUR 24588–24590) collected from Municipality of Cauayan, Negros Occidental Province, Negros Island, Philippines. Three specimens ( CAS 134298, 137789, CAS-SUR 26776) collected from Negros Occidental Province, Negros Island, Philippines. Twenty specimens ( CAS 137653, 137672, 137790, 138096, 138134, 139258, 145791, 145792, 145804–6, 145875, 145876, 145976, 173760, 185991, 200539, 200540, CAS-SUR 24323, 24829) collected from Municipality of Pamplona, Negros Oriental Province, Negros Island, Philippines. One specimen (CAS-SUR 26775) collected from Municipality of Siaton, Negros Oriental Province, Negros Island, Philippines. Thirty specimens ( CAS 128955, 128957, 128958, 128960–62, 128964–70, 128972–78, 131796, 132609, 142039–46) collected from Municipality of Sibulan, Negros Oriental Province, Negros Island, Philippines. Thirteen specimens ( CAS 133055, 137791, 200538, CAS-SUR 21803, 21839, 21840, 21856, 21857, 21872, 22218–20, 24385) collected from Negros Oriental Province, Negros Island, Philippines.

Diagnosis. Pseudogekko atiorum can be distinguished from congeners by the following combination of characters: (1) body size moderate (SVL 41.1–52.5 mm); (2) axilla–groin distance moderate (19.4–28.4 mm); (3) head length moderate (7.4–9.4 mm); (4) snout length long (4.3–5.8 mm); (5) Toe-IV scansors 14–17; (6) paravertebral scales 226–240; (7) ventral scales 119–129; (8) supralabials 15–17; (9) infralabials 12–15; (10) circumorbitals 35–38; (11) precloacal pores 13–15; (12) femoral pores absent; (13) dominant body coloration dark brown; (14) conspicuous head spotting present, cream; (15) conspicuous dorsolateral spotting present, cream; (16) conspicuous limb spotting absent; (17) tail banding absent; (18) body striping absent; (19) interorbital banding present, light brown; (20) iris ring coloration absent ( Tables 1 , 2 ; Figs. 3–6 ).

Comparisons. Characters distinguishing Pseudogekko atiorum from all other species of Pseudogekko are summarized in Tables 1–3 . Pseudogekko atiorum most closely resembles P. b rev i pe s; however, it differs from this species by having a longer snout–vent length in both males (41.1–52.5 mm vs. 39.0) and females (44.8–48.7 mm vs. 34.5–42.4), longer eye–nares distance (3.5–4.5 mm vs. 3.0–3.4), a tendency towards having both a longer snout length (4.3–5.8 mm vs. 3.8–4.4) and internares distance (1.5–1.9 mm vs. 1.2–1.6), and a greater number of supralabials (15–17 vs. 13 or 14), circumorbitals (35–38 vs. 33–35), paravertebrals (226–240 vs. 211–218), ventrals (119–129 vs. 96–117), and precloacal pores (13–15 vs. 12; Figs. 3–5 ).

Pseudogekko atiorum can be distinguished from P. chavacano by having a shorter snout–vent length (41.1– 52.5 mm vs. 54.7–55.9), longer head length (7.4–9.4 mm vs. 10.4), a tendency towards a shorter snout length (4.3– 5.8 mm vs. 5.8–6.0), fewer infralabials (12–15 vs. 16 or 17), circumorbitals (35–38 vs. 46), and precloacal pores (13–15 vs. 16), greater number of paravertebrals (226–240 vs. 195–197), cream colored (vs. neon green) head and dorsolateral spotting, absence (vs. presence) of limb spotting and tail banding, and presence of interorbital banding (vs. absence); from P. compresicorpus by having a shorter snout–vent length (41.1–52.5 mm vs. 54.9–59.7), a tendency towards both a shorter axilla–groin distance (19.4–28.4 mm vs. 27.0–32.6) and head length (7.4–9.4 mm vs. 9.2–11.3), fewer Toe-IV scansors (14–17 vs. 18 or 19) and circumorbitals (35–38 vs. 39–45), cream colored (vs. neon green) head and dorsolateral spotting, absence (vs. presence) of limb spotting and a light blue iris ring, and presence (vs. absence) of interorbital banding; from P. di t o y by having fewer infralabials (12–15 vs. 16 or 17) and circumorbitals (35–38 vs. 40–43), greater number of paravertebrals (226–240 vs. 180–185) and ventrals (119–129 vs. 111–118), fewer precloacal pores (13–15 vs. 18), and the presence (vs. absence) of head spotting, dorsolateral spotting, and interorbital banding; from P. pungkaypinit by having a shorter snout–vent length (41.1–52.5 mm vs. 66.6–75.3), axilla–groin distance (19.4–28.4 mm vs. 37.2–41.2), total length (80.2–113.5 mm vs. 125.3–141.2), midbody width (4.8–7.7 mm vs. 7.7–9.1), head length (7.4–9.4 mm vs. 11.4–13.6), head width (5.9–8.3 mm vs. 9.3–11.2), and snout length (4.3–5.8 mm vs. 6.7–7.5), fewer Finger-III scansors (12–14 vs. 15–17), infralabials (12–15 vs. 17–19), circumorbitals (35–38 vs. 50–55), paravertebrals (226–240 vs. 265–280), and precloacal pores (13–15 vs. 17–20), a tendency towards having fewer ventrals (119–129 vs. 125–155), the presence (vs. absence) of head and dorsolateral spotting and interorbital banding, and the absence (vs. presence) of body striping; from P. smaragdinus by a tendency towards having a shorter snout–vent length (41.1–52.5 mm vs. 50.2–64.3) and axilla– groin distance (19.4–28.4 mm vs. 26.2–35.5), fewer Finger-III scansors (12–14 vs. 15–18), paravertebrals (226– 240 vs. 241–252), and enlarged pores (13–15 vs. 32–41), a tendency towards having fewer Toe-IV scansors (14–17 vs. 16–22) and supralabials (15–17 vs. 16–19), greater number of circumorbitals (35–38 vs. 33–35), presence of dark brown (vs. yellow to orange [undisturbed] or neon green [disturbed]) body coloration, cream colored (vs. large black and small white) head and dorsolateral spotting, presence (vs. absence) of interorbital banding, and absence (vs. presence) of limb spotting and tail banding.

Description of holotype. Adult female in excellent condition; small incision in the sternal region (portion of liver removed for genetic sample). Body small, slender, SVL 44.8 mm; limbs well developed, moderately slender; tail slender; margins of limbs smooth, cutaneous flaps or dermal folds absent.

Head size moderate, slightly differentiated from neck, characterized by only slightly hypertrophied temporal and adductor musculature; snout broadly rounded in dorsal view and bluntly rounded in lateral view; HW 96.9% MBW, 83.6% HL; HL 18.4% SVL; SNL 70.7% HW, 59.2% HL; dorsal surfaces of head relatively homogeneous, with slightly to moderately pronounced concave postnasal, internasal, prefrontal, and interorbital concavities; auricular opening small, nearly round, beneath temporal swellings on either side of head; tympanum deeply sunken; orbit large; eye large, pupil vertical, margin wavy; limbs and digits relatively short; thighs moderately thicker compared to upper arms; TBL 8.0% SVL, 57.9% FL.

Rostral size moderately large, margin in wide heart shape in anterodorsal view, nearly as broad as high, sutured anterolaterally with anteriormost enlarged supralabials, projecting onto dorsal surface of head to point in line with anteriormost edge of nasal; nasal surrounded by first labial, rostral, one enlarged postnasal, and two enlarged supranasals; medial supranasals separated by 3 small median scales; enlarged supranasals moderately larger than postnasals; circumorbitals 36 in total.

Total number of differentiated supralabials 15, bordered dorsally by one row of differentiated, slightly enlarged snout scales; total number of differentiated infralabials 12, bordered ventrally by 2 or 3 rows of slightly enlarged scales; chin scales enlarged; postrictal scales undifferentiated; gulars small, round, nonimbricate.

Dorsal cephalic scales fairly homogeneous in size, shape, disposition, and distribution; cephalic scalation slightly convex, round to oval scales; postnasal, prefrontal, internasal, and interorbital depressions; undifferentiated posterior head scales granular, slightly convex.

Axilla–groin distance 55.1% SVL; undifferentiated dorsal body scales round to tubular, moderately to sharply convex, juxtaposed, relatively homogeneous in size, many with raised edge, irregular in placement on individual scales across body; each dorsal scale surrounded by 4–6 interstitial granules; dorsals gradually transition to imbricate ventrals along lateral body surface; paravertebrals between midpoints of limb insertions 232; ventrals between midpoints of limb insertions 128; scales on dorsal surfaces of limbs more imbricate than dorsals; scales on dorsal surfaces of hands and feet similar to dorsal limb scales, heavily imbricate; ventral body scales flat, cycloid, strongly imbricate, much larger than lateral or dorsal body scales, relatively homogeneous in size.

Fourteen enlarged scales in continuous precloacal series (pore-bearing series in males), arranged in a widely obtuse, “V”-formation; patch of slightly enlarged scales posterior to precloacal series, roughly three scale rows in width, 3–4 scale rows in length, forming an oval patch just posterior to precloacal series.

Digits moderately expanded and covered on palmar and plantar surfaces by bowed, unnotched, undivided scansors; digits with minute vestiges of interdigital webbing; subdigital scansors of fingers (left/right) I (9,8), II (10,10), III (13,13), IV (14,14), V (9,9); subdigital scansors of toes (left/right) I (9,9), II (10,10), III (13,13), IV (15,15), V (12,12); mite eggs visible between distal subdigital scansors of digits on hands and feet; subdigital scansors of hands and feet bordered proximally (on palmar and plantar surfaces) by two or three slightly enlarged scales that form a near-continuous series with enlarged scansors; all digits clawed, but first (inner) claw greatly reduced; remaining terminal claw-bearing phalanges compressed, with moderately sized recurved claws.

brevipes atiorum chavacano compresicorpus ditoy pungkaypinit smaragdinus sp. A (1 m, 3 f) (8 m, 7 f) (1 m, 1 f) (3 m, 5 f) (1 m, 1 f) (4 m, 2 f) (16 m, 17 f) (1 m, 1 f) individuals showing specific counts are given in parentheses. Characters summarized for adult specimens only. When coloration in life has not been documented,

characters are listed as unkown.

Enlarged pore series 12 (precloacal) 13–15 16 (precloacal) 10–14 (precloacal) 18 (precloacal) 17–20 (precloacal) 32–41 15

(precloacal) (precloacofemoral) (precloacal) Femoral pores – – – – – – + –

……continued on the next page Tail relatively long compared to body, TL 44.6 mm, 99.4% SVL; round, not heavily depressed; TH 87.8% TW; caudals similar in size to dorsals, subcaudals similar in size to ventrals.

Coloration of holotype in preservative. Background dorsal trunk coloration light tan with intermittent small cream and dark brown speckles, continuing down the tail; dorsal region of the head with similar color pattern, except for a pronounced dark brown area above the orbits; a ridge of raised, dark brown scales present in the postnasal region; dorsal and lateral regions of the limbs with the same color pattern as the trunk; supralabials with the same pattern as the head, whereas the infralabials are a solid cream with few medium brown speckles; ventral side of the trunk has a cream background color, with the speckling pattern of the lateral side of the body wrapping around to approximately halfway to the midpoint of the venter; ventral side of the head has only sparse medium brown speckling; ventral region of the tail is solid cream with occasional light brown speckles that increase in intensity towards the tail tip; ventral regions of the limbs, hands, and feet are cream with medium to dark brown speckles scattered sparsely throughout; the space between the scansors is a medium brown.

Coloration of holotype in life. Dorsal ground color of head, trunk, and tail chocolate brown; gradual transition to lighter coloration towards tip of the snout; light mottling posterior to eyes and along neck; dorsal limb surfaces colored as trunk, but with randomly distributed light blotches; tail lighter colored than trunk, but with series of longitudinally elongate, paravertebral cream blotches.

Measurements and scale counts of holotype in mm. SVL 44.8; axilla–groin distance 24.7; total length 89.4; tail length 44.6; head length 8.3; head width 6.9; head height 4.7; eye diameter 3.1; snout length 4.9; eye–nares distance 4.0; internarial distance 1.6; interorbital distance 4.0; midbody width 7.1; femur length 6.2; tibia length 3.6; Toe-I length 2.1; Toe-IV length 3.9; tail width 2.5; tail height 2.2; supralabials 15; infralabials 12; circumorbitals 36; paravertebral scales 232; ventral scales 128; Finger-III scansors 13; Toe-IV scansors 15.

Distribution, ecology and natural history. Pseudogekko atiorum is known only from Negros and Siquijor islands, although it is possible that it will eventually be discovered on other islands in the Western Visayan Faunal Region (i.e., Cebu, Panay; Fig. 1 ; Ferner et al., 2001). Pseudogekko atiorum represents the only species of Philippine false gecko distributed in the western Visayan islands, with the remaining diversity in the genus restricted to the northern, eastern, and sounthern islands of the archipelago ( Siler et al., 2014b, c). Although believed to be primarily an obligate forest species, at least one individual has been collected recently on the leaves of a banana plant at mid-elevation on Mt. Talinis in southeast Negros Island ( PNM 9518). This individual was found within a small patch of disturbed forest where an agricultural plot had been established, surrounded by pristine secondary growth forest. Among all members of the genus, P. a t i or um is the best represented in museum collections, with 87 individuals housed at CAS and KU alone. Although historical collections reported this species to be quite common, recent expeditions over the last decade resulted in few observations of this Western Visayan gecko in the wild. Due to the absence of data allowing for confirmation of potential declines in population size and health resulting from widespread habitat destruction, and the lack of available information about the species ecology and intraspecific diversity, we do not find this species qualifies for Critically Endangered, Endangered, Vulnerable, or Near Threatened status under the IUCN criteria for classification (IUCN, 2013). Therefore, we recommend that the species be considered Least Concern at the current time, but strongly recommend that immediate efforts be made to study the health of wild populations of this species on Negros Island and, especially, Siquijor Island where no original forest persists (CDS, RMB, personal observations) but a small patch of protected secondary forest may protect this species.

Etymology. We derive the new species name in honor of the Ati people, a Negrito ethnic group believed to be among the first to colonize the central Philippines. Similar to this new species of Pseudogekko, Inati (the native language of the Ati), is infrequently encountered and possibly threatened, and is estimated to be spoken by fewer than 2,000 people. The specific epithet is a noun of masculine gender. Suggested common name: Central Visayan False Gecko.

Figures

FIGURE 1. Map of the Philippine islands showing the sampling localities and recognized distributions for Pseudogekko brevipes and P. atiorum. Simplified phylogeny taken from Siler et al. (2014 b, c), showing hypothesized relationships of Philippine Pseudogekko resulting from Bayesian analyses of a concatenated multilocus molecular dataset shown for reference with Bayesian posterior probabilities.

FIGURE 3. Illustrations of precloacal pore series in adult male specimens of Pseudogekko atiorum (CAS 128963; paratype) and P. brevipes (SMF 8988; holotype). Scale bars = 2 mm. Illustrations by CDS and CW.

FIGURE 4. Photographs of the preserved holotype of Pseudogekko atiorum (PNM 9518, formerly KU 302818). Photographs show a lateral and ventral view of the head and a dorsal view of the body. Scale bars = 3 mm. Photographs taken by JLW.

FIGURE 5. Illustration of lateral view of head of adult male Pseudogekko atiorum (CAS-SUR 26778; paratype) from Negros Island, Philippines. Scale bar = 3 mm. Illustration by NAH and CDS.

FIGURE 6. Photographs in life of adult female Pseudogekko atiorum (TNHC 62478; paratype) from Negros Island, Philippines. Photographs taken by RMB.

Tables

TABLE 1. Summary of mensural characters in all known species of Pseudogekko. Sample size, body length and total length among males (m) and females (f), and general geographical distribution are included for reference. Characters summarized for adult specimens only. SVL, AGD, TotL, MBW, HL, HW, and SNL given as a range (mm) over mean ± standard deviation; all body proportions given as a range (percentage) over mean ± standard deviation.

Range SVL (m)	Mindanao Faunal Region 39.0	Western Visayan Faunal Region 41.1–52.5 (47.0 ± 4.5)	Western Mindanao Island 55.9	Luzon Faunal Region Samar & Leyte Mindanao Faunal islands Region 55.9–58.8 49.4 66.6–76.8 (57.6 ± 1.5) (71.8 ± 5.1)	Polillo Island & Bicol Peninsula (Luzon Island) 54.2–64.3 (59.4 ± 2.5)	Romblon Island Group 63.4
SVL (f)	34.5–42.4 (38.6 ± 4.0)	44.8–48.7 (46.3 ± 1.5)	54.7	54.9–59.7 52.6 75.2–75.3 (57.1 ± 2.6)	50.2–61.7 (57.4 ± 3.5)	62.1
AGD	17.8–29.8 (21.7 ± 5.5)	19.4–28.4 (24.8 ± 2.4)	26.7–30.0	27.0–32.6 25.1–29.7 37.2–41.2 (30.4 ± 1.8) (39.6 ± 1.8)	26.2–35.5 (31.5 ± 2.2)	32.1–33.0
TotL	72.0–87.5 (77.3 ± 7.3)	80.2–113.5 (97.3 ± 13.0)	95.8	105.9–117.3 — 125.3–141.2 (111.7 ± 5.7) (135.2 ± 8.6)	103.6–129.7 (119.4 ± 6.4)	—
MBW	4.5–5.8 (4.9 ± 0.6)	4.8–7.7 (6.1 ± 1.0)	6.4–6.7	5.4–8.5 6.3–7.3 7.7–9.1 (6.3 ± 1.0) (8.2 ± 0.6)	6.2–10.4 (8.1 ± 1.0)	8.5–9.9
HL	6.2–9.5 (7.4 ± 1.5)	7.4–9.4 (8.5 ± 0.6)	10.4	9.2–11.3 9.3–9.6 11.4–13.6 (9.7 ± 0.3) (12.6 ± 0.9)	7.8–10.7 (9.5 ± 0.7)	11.7–11.8
HL/SVL	16.7–24.4 (19.2 ± 3.6)	16.0–19.8 (18.3 ± 0.9)	18.6 –19.1	16.1–18.1 18.2–18.9 16.0–18.3 (17.1 ± 0.7) (17.2 ± 0.8)	14.9–17.4 (16.3 ± 0.6)	18.6–18.9
HW	5.6–6.5 (5.9 ± 0.5)	5.9–8.3 (7.1 ± 0.7)	7.8–8.5	7.5–10.1 7.7–7.9 9.3–11.2 (8.2 ± 0.8) (10.6 ± 0.9)	7.1–9.8 (8.6 ± 0.6)	7.4–10.1
HW/SVL	14.2–16.8 (15.2 ± 1.2)	14.3–16.4 (15.3 ± 0.6)	14.3–15.2	13.0–16.3 14.7–15.9 14.0–15.2 (14.2 ± 1.0) (14.7 ± 0.4)	13.8–16.0 (14.8 ± 0.6)	15.2–16.0
SNL	3.8–4.4 (4.1 ± 0.2)	4.3–5.8 (5.1 ± 0.4)	5.8–6.0	5.3–7.4 5.4–5.7 6.7–7.5 (5.9 ± 0.7) (7.2 ± 0.4)	4.9–6.5 (5.7 ± 0.4)	7.2–7.5
SNL/HL	44.4–62.3 (56.5 ± 8.3)	55.1–69.1 (59.5 ± 3.7)	55.2–58.0	56.1–64.6 57.4–59.3 53.6–68.4 (59.6 ± 3.0) (60.0 ± 4.8)	50.7–67.9 (60.3 ± 2.9)	61.9–64.1

TABLE 2. Summary of qualitative diagnostic characters (meristic; present, absent) in all known species of Pseudogekko. In cases of scale count variation within species, numbers

	brevipes (1 m, 3 f)	atiorum (8 m, 7 f)	chavacano (1 m, 1 f)	compresicorpus (3 m, 4 f)	ditoy (1 m, 1 f)	pungkaypinit (4 m, 2 f)	smaragdinus (16 m, 17 f)	sp. A (1 m, 1 f)
FinIIIscan	12(4)	12(3) 13 (9) 14 (3)	15 (1) 16 (1)	15 (4) 16 (2) 17 (1)	14 (1) 15 (1)	15 (3) 16 (1) 17 (2)	15 (1) 16 (4) 17 (9) 18 (19)	13 (2)
ToeIVscan	15(4)	14(1) 15 (2) 16 (2) 17 (10)	17 (1) 20 (1)	18 (5) 19 (2)	16 (1) 17 (1)	17 (1) 18 (2) 19 (2) 21 (1)	16 (1) 18 (6) 19 (8) 20 (12) 21 (5) 22 (1)	17 (2)
SL	13(2) 14 (2)	15 (7) 16 (4) 17 (4)	15 (1) 16 (1)	16 (1) 17 (1) 18 (3) 19 (1) 20 (1)	17 (1) 20 (1)	16 (1) 18 (2) 19 (2) 20 (1)	16 (8) 17 (10) 18 (11) 19 (4)	20 (1) 21 (1)
IFL	14(1) 15 (3)	12 (1) 13 (4) 14 (9) 15 (1)	16 (1) 17 (1)	13 (1) 15 (2) 16 (4)	16 (1) 17 (1)	17 (4) 18 (1) 19 (1)	14 (6) 15 (12) 16 (10) 17 (5)	17 (1) 19 (1)
CO	33–35	35–38	46, 46	39–45	40, 43	50–55	33–35	50 (1) 54 (1)
PVS	211–218	226–240	195, 197	226–234	180, 185	265–280	241–252	240–246
VS	96–117	119–129	122, 123	127–130	111, 118	125–155	124–130	135–141