Phyllodactylus ngiwa, Ramírez-Reyes & Durán-Arceo & Palacios-Aguilar & Flores-Villela, 2025

Ramírez-Reyes, Tonatiuh, Durán-Arceo, Daniel R., Palacios-Aguilar, Ricardo & Flores-Villela, Oscar, 2025, Taxonomic revision of the polyphyletic Phyllodactylus bordai (Squamata: Phyllodactylidae), with the description of a new species, Zootaxa 5722 (2), pp. 151-183 : 165-171

Phyllodactylus ngiwa sp. nov.

Phyllodactylus bordai (in part) Dixon (1964), Casas-Andreu et al. (1996), Murphy et al. (2009), Canseco-Márquez & Gutiérrez-Mayen (2010), Lara-Reséndiz et al. (2013), Mata-Silva et al. (2015; 2021), Woolrich-Piña et al. (2017), Ramírez-Reyes et al. (2017; 2020; 2022), Lemos-Espinal & Smith (2020; 2024).

Holotype. Adult male ( MZFC-HE 37273 ) collected ~ 2 km N of San Juan Bautista Cuicatlan Botanical Garden, municipality of San Juan Bautista Cuicatlán, Oaxaca, Mexico ( 17.821888 N, - 96.963666 W WGS84 ), on October 22, 2024, by Tonatiuh Ramírez Reyes, Ricardo Palacios Aguilar, and Daniel R. Duran Arceo.

Paratypes (12). Adult female ( MZFC-HE 37264 ), adult male ( MZFC-HE 37265 ), and adult male ( MZFC-HE 37266 ) collected at Cabañas Zapotitlan Salinas Botanical Garden , Puebla ( 18.328972, -97.452972) on October 21, 2024 ; adult male ( MZFC-HE 37267 ) and adult female ( MZFC-HE 37268 ) collected 200 m SE from Cabañas Zapotitlan Salinas Botanical Garden , Puebla ( 18.326888, -97.453388) on October 21, 2024 ; adult male ( MZFC-HE 37271 ), adult female ( MZFC-HE 37272 ), and adult female ( MZFC-HE 37274 ) collected ~ 2 km N of San Juan Bautista Cuicatlan Botanical Garden, municipality of San Juan Bautista Cuicatlán , Oaxaca ( 17.821888 N, - 96.963666 W WGS84 ), on October 22, 2024 ; adult female ( MZFC-HE 37278 ), adult male ( MZFC-HE 37279 ), adult female ( MZFC-HE 37280 ), and adult female ( MZFC-HE 37281 ) collected 2 km N of San Juan Bautista Cuicatlan Botanical Garden, municipality of San Juan Bautista Cuicatlán , Oaxaca ( 17.824944 N, - 96.963666 W WGS84 ). All paratypes were collected by Tonatiuh Ramírez Reyes, Ricardo Palacios Aguilar, and Daniel R. Duran Arceo .

Etymology. According to government information, eight indigenous ethnic groups live within the Tehuacan-Cuicatlan Valley. One of these is known as the Popolocas (SEMARNAT-CONANP 2013), a colloquial but imprecise term to refer to speakers of the Ngiwa language (Ngiwa people). We selected the name of this indigenous people because the territory of Ngiwa language speakers is similar to the distribution of P. ngiwa sp. nov. (southern Puebla and northern Oaxaca). Ngiwa means “the inhabitants or owners of the plains”, which recognizes the pride of belonging to a specific geographic region that implies an identity based on beliefs, traditions, thoughts, uses, and customs that have been conferred to the Ngiwa people ( INALI 2020).

Common name. Tehuacan-Cuicatlan Valley gecko, salamanquesa del Valle de Tehuacan-Cuicatlan.

Diagnosis. To compare values of measurements and counts, we give more weight in this section to the values reported in the monographic reviews by Dixon (1964; 1966) for the high number of specimens analyzed and scientific collections visited, as well as to the original descriptions for each species, taking into account the taxonomic changes that have occurred to date. Phyllodactylus ngiwa is a medium-sized gecko species (mean SVL = 47.7 mm, max. SVL = 59.9 mm, median SVL = 50.5 mm) whose distribution is limited to the Tehuacan-Cuicatlan Valley in the southern Mexican states of Puebla and Oaxaca.

Although body size is a character with limited information for differentiating P. ngiwa from other Phyllodactylus species in Mexico, the combination of longitudinal and transversal counts of ventral scales allows for differentiating all species belonging to Clade I ( Table 5): P. ngiwa (mean LVS = 48.1, mean TVS = 25.1), P. bordai (mean LVS = 56.8, mean TVS = 28), Phyllodactylus from Morelos (mean LVS = 45, mean TVS = 22.8), P. isabelae (mean LVS = 69.4, mean TVS = 28.7), P. kropotkini (mean LVS = 67, mean TVS = 30), P. papenfussi (mean LVS = 50.3, mean TVS = 24.3), P. benedettii (mean LVS = 62.6, mean TVS = 22), P. lupitae (mean LVS = 73.1, mean TVS = 27.5), P. lanei (mean LVS = 65, mean TVS = 30.2), P. rupinus (mean LVS = 69, mean TVS = 34). This combination of characters also differentiates between species belonging to Clades II and III: P. magnus (mean LVS = 58.9, mean TVS = 27.2), P. saxatilis (mean LVS = 55, mean TVS = 26.3), P. cleofasensis (mean LVS = 61, mean TVS = 27.2), P. davisi (mean LVS = 57.6, mean TVS = 31), P. muralis (mean LVS = 61.6, mean TVS = 29.6), P. delcampi (mean LVS = 72.9, mean TVS = 30), P. homolepidurus (mean LVS = 59.9, mean TVS = 30.3), P. nolascoensis (mean LVS = 59, mean TVS = 30), P. santacruzensis (mean LVS = 57, mean TSV = 34), P. partidus (mean LVS = 61, mean TVS = 30), P. xanti (mean LVS = 59.7, mean TVS = 33.6), P. nocticolus (mean LVS = 65, mean TVS = 36), P. unctus (mean LVS = 58, mean TVS = 29.4), P. bugastrolepis (mean LVS = 48, mean TVS = 29), P. duellmani (mean LVS = 50, mean TVS = 23.6), P. paucituberculatus (mean LVS = 63.7, mean TVS = 25.2), P. apricus (mean LVS = 62, mean TVS = 38), P. coronatus (mean LVS = 63, mean TVS = 33), P. angelensis (mean LVS = 62, mean TVS = 36). Despite P. ngiwa having a unique combination of mean values for the two different counts of ventral scales, three species ( P. papenfussi , P. bugastrolepis , and P. duellmani ) present similar mean values and likely show overlapping values or even display the same combination in some individuals. In this case, other combinations of characters can be used to differentiate these four species. In the case of P. papenfussi , adult body size is highly informative, since this is the smallest species of Phyllodactylus in Mexico (adult SVL 30.3–36.6, 33.95 ± 2.1; juvenile SVL 22.5 and 28.9; Murphy et al. 2009); meanwhile, adult P. ngiwa reach a maximum SVL of 59.9 mm, nearly double the size of P. papenfussi . Additionally, P. ngiwa has 19.5 interorbital scales, 21.9 paravertebral tubercles, and 5.7 axilla-groin tubercles, while P. papenfussi presents 17.5 interorbital scales, 33.2 paravertebral tubercles, and 18.9 axilla-groin tubercles ( Murphy et al. 2009). Furthermore, the number of labial scales in contact with the postmental scales vary in P. ngiwa , with the most frequent combination being 2-2 (66.6%), while in P. papenfussi this character does not vary from the combination of 1-1 (100%) ( Murphy et al. 2009). Phyllodactylus duellmani is also a small species of gecko (maximum known SVL: 43 mm) and presents 15.6 interorbital scales, 37.1 paravertebral tubercles, 24 axilla-groin tubercles, and lacks tubercles on the tail ( Dixon 1964), unlike P. ngiwa (19.5 interorbital scales, 21.9 paravertebral tubercles, 5.7 axilla-groin tubercles, and 4.7 tail tubercles). Finally, P. bugastrolepis is a medium species of insular gecko (maximum known SVL: 49 mm), presents 23 interorbital scales, 39 paravertebral tubercles, 15 rows of dorsal tubercles, and 23 axilla-groin tubercles ( Dixon 1966). The combination of morphometric, meristic, and climatic characteristics allows us to identify and differentiate P. ngiwa populations from the rest of the Phyllodactylus species and populations in Mexico.

Description of holotype. Adult male, medium build (body not robust), head not strongly flattened, presents a slight depression on the snout region (between the region of the eye orbits and nostril), neck not constricted, slightly differentiated from the body. The specimen presents a slight constriction in the anterior region of each ocular orbit, inflated loreal region, and internal scales present a slight constriction. Rostral scale wider than long, with no marks or sutures (i.e., is completely smooth), only denoting a slight U-shaped depression. Nostril in contact with the rostral scale, the first labial scale contacts a postnasal scale, two large internasal scales in contact with five postnasal scales, the internasal scales tend to be as long as wide, both in close contact, no scale intervenes between them. The specimen presents 10 supralabial scales (right side) and nine supralabial scales (left side), followed by four and five smaller scales following a commissure towards the anterior part of the head; eight infralabial scales (right side), seven infralabial scales (left side), followed by two small scales only on the left side below the anterior commissure. The specimen has 14 interorbital scales in the middle part, 13 interorbital scales at the anterior edge of the eye orbits, five rows of irregular palpebral scales, the last five palpebral scales anteriorly ending in a sharp point. The specimen has 26 scales across the snout from the fourth labial scales, 18 scales across the snout from the third labial scales, the scales bordering the supralabials are flat but not imbricated. Eye size moderate, its diameter slightly bigger than the snout length, auricular opening small denticulate (but not strongly denticulate). Scales in the occipital region of the head are granular, different in shape from the interorbitals (which are elongated). Tubercles are found intercalated (but not strongly keeled nor of great size or volume), circular in shape, and mixed in with small circular scales. The mental scale is subtriangular, with the edge that is in contact with the rostral wider than the rostral itself. Postmental scales in contact with six total scales, including two labials (having more contact with the first labial on both left and right sides). The body has granular scales, with 14 rows of dorsal tubercles counted at the middle of the body, 10 rows of tubercles at the base of the neck, and four rows at the base of the tail. Ventral scales in 27 rows clearly differentiated from the ventral marginal-lateral scales, which are flattened and progressively intercalated with the dorsal scales. Scales on the forelimbs are slightly imbricated towards the base of the limb insertion, becoming flatter near the toes; in the dorsal view, irregular tubercles are interspersed and not strongly keeled, while in the ventral view the forearm scales are smaller and slightly imbricated compared to those of the arm. Dorsal scales on the posterior limbs are granular, interspersed with strongly keeled tubercles; scales on the ventral region of the pads are homogeneous and similar to the ventral scales near the cloaca. Scales surrounding the cloaca and on the ventral thigh region are small, imbricated, and speckled with very small black dots. Lamellar formulas are as follows: right anterior: 7-8-10-10-9, left anterior: 7-8-10-11-7, right posterior: 7-9-10-11-10, left posterior: 6-8-11-12-11. Most of the digital lamellae are undivided and consist of a single complete lamella ( Fig. 9 ).

Terminal digital toepads resemble imperfect rectangles, longer than wide, and very uniform on all four toepads. The tail is dorsally ringed. Ventrally, the tail has a series of 39 flattened scales in the central region clearly differentiated from the rest, before dividing posteriorly into 14 divided scales up to the tip of the tail. Dorsal tail scales are very homogeneous, with scarce tubercles interspersed.

Measurements (in mm). SVL (54.73), AGL (24.77), HW (11.28), SEL (6.02), ED (4.09), AO (2.39), WOO (5.20), IL (1.70), 4AR (5.05), 4 PR (5.40), 4AL (5.10), 4PL (4.84), AOEL (2.36), TL (59.33), TW (8.03), HL (16.89), HH (6.67).

Counts. SBP (6), SPLC (2-2), IS (15), TLSS (19), SBI (5), TVS (27), LVS (48), BTT (4), LTT (4), DTR (13), NES (10), 4DLAR (10), 4DLAL (11), 4DLPL (11), 4DPLR (11), PT (23), HT (16), AGT (22), INFRA (7), SUPRA (10).

Variation. All morphometric measurements and meristic counts are presented with mean, standard deviation, and median values in Tables 4 and 5, respectively. We also provide the raw measurement (in mm) and counts values of each P. ngiwa specimen in Supplementary Table 6, as well as measurements and counts of the type series ( holotype and paratypes) in Supplementary Table 7.

Coloration pattern (in life). The background color of the body is light, creamy-yellowish, while the belly is white, with slight yellowish tones on the ventral margins. Dorsally, irregular spots ranging from light to dark brown and even black are intermixed against the light background color. The tail color pattern consists of dark bands of dark brown to black scales interspersed with light bands the color of the dorsal skin; however, the dark bands gradually fade toward the ventral part of the tail. The head has a pigmented band that crosses the eye from the nostril to the auricular opening; although this band is visible, the coloration is not strongly pronounced. The dorsal region of the head has irregular dark-toned spots, although, as with the entire body, they are not deeply marked. The eyes are copper-colored with a black vertical pupil ( Fig. 10 ). This dorsally mottled coloration pattern is typical in Phyllodactylus and probably serves as camouflage, allowing these geckos to blend in with the natural habitat where they are distributed ( Fig. 11 ).

Distribution and habitat. Phyllodactylus ngiwa sp. nov. is endemic to the Tehuacan-Cuicatlan Valley within the Mexican states of Puebla and Oaxaca. According to Canseco-Márquez & Gutiérrez-Mayén (2010), P. ngiwa is widely distributed in the valleys of Tehuacan ( Puebla) and Cuicatlan ( Oaxaca), although its populations are likely found in the low and medium altitude regions of both valleys ( Fig. 12 ). This region constitutes a phytogeographic province by the same name (Tehuacan-Cuicatlan Valley), which is located between 17º 48’ 18º 58’ Latitude (N) and 97º 03’ 97º 43’ Longitude (W) and covers an area of approximately 10,000 km 2 ( Villaseñor et al. 1990; Valiente-Banuet et al. 2000; 2009; Canseco-Márquez & Gutiérrez-Mayén, 2010). More broadly, this region is part of the Mixteca-Oaxaqueña physiographic province that includes several valleys, among which the most notable are Cuicatlan, Huajuapan, Tehuacan, Tepelmeme, and Zapotitlan, which in turn are part of the Upper Basin of the Papaloapan River and, to a lesser extent, the Upper Basin of the Balsas River ( Villaseñor et al. 1990; Valiente-Banuet et al., 2000; 2009; Canseco-Márquez & Gutiérrez-Mayén, 2010). Due to the complex topography and the influence of bordering mountain ranges, particularly in the eastern portion, the TCV presents diverse climates (warm, semi-warm, and temperate) according to latitudinal and altitudinal gradients ( Valiente-Banuet et al., 2000; 2009; Canseco-Márquez & Gutiérrez-Mayén, 2010). Canseco-Márquez & Gutiérrez-Mayén (2010) recognize six main plant groups: 1) vegetation dominated by arborescent cacti (columnar cactus forests), 2) wooded vegetation of lowland areas (less than 1,800 m above sea level), including low deciduous and Yucca forests, 3) wooded vegetation of higher altitudes (from 1,900 to 2,900 m above sea level), including Juniperus , Quercus , coniferous, pine-oak, and Alnus forests, as well as palm groves and mountain izotales, 4) wooded and herbaceous vegetation associated with year-round rivers, including gallery forests and “tular” ( Typha domingensis ), 5) shrubs dominated by thorny bushes, including three types of scrub and the “candelillar” ( Euphorbia antisyphilitica ), and 6) groups of evergreen and thornless shrubby plants, comprising two types of scrub (for a detailed description see Valiente-Banuet et al. 2009 and Canseco-Márquez & Gutiérrez-Mayén 2010).

According to the most recent revision, the herpetofauna of the Tehuacan-Cuicatlan Valley is composed of 117 species, of which 32 are amphibians (8 families and 15 genera) and 85 are reptiles (19 families and 49 genera) (for a detailed study, see Canseco-Márquez & Gutiérrez-Mayén 2010). For mammals, Téllez-Valdés et al. (2010) report the existence of 98 species (20 families and 64 genera) within the Tehuacan-Cuicatlan Valley, including the puma ( Puma concolor), white-tailed deer ( Odocoileus virginianus ), skunk ( Mephitis macroura ), fox ( Urocyon cinereoargenteus ), coyote ( Canis latrans ), raccoon ( Procyon lotor ), and badger ( Nasua narica ), as well as the river otter ( Lontra longicaudis ) in the La Cañada area.

The most significant conservation area within the TCV is the Tehuacan-Cuicatlan Biosphere Reserve ( RBTC) ( Fig. 12 ). This reserve spans 51 municipalities, 20 in southeastern Puebla and 31 in northwestern Oaxaca ( Figures 12 and 13 ), and encompasses a total area of more than 490,000 hectares (SEMARNAT-CONANP 2013) .

Natural history. Similar to most Phyllodactylus leaf-toed geckos in Mexico, little is known about the natural history of P. ngiwa . According to Canseco-Márquez & Gutiérrez-Mayén (2010), P. ngiwa is a common, nocturnal species found in the semi-arid region, distributed over a wide altitudinal range ( 450–1130 masl). This species lives in rock crevices, dry cacti, slightly disturbed environments (cabins, bridges), and ruined and abandoned buildings (Canseco-Márquez & Gutiérrez-Mayén 2010; Lara-Reséndiz et al. 2013; pers. obs.). The diet of this species is based on insects, including beetles ( Coleoptera , Elateridae , and Cerambycidae ), small butterflies (Lepidoptera), spiny bugs (Homoptera, Aetalionidae ), ants ( Hymenoptera , Formicidae ), crickets ( Orthoptera , Gryllidae ), as well as spiders (Order Araneae ), woodlice (Isopoda), and centipedes (Order Scolopendromorpha ). It is an oviparous species, with females laying up to two eggs; pregnant females have been observed between March and May in Santa María Texcatitlán, Oaxaca, and juveniles between July and September in Zapotitlán Salinas, Puebla and Santiago Quiotepec, Oaxaca (Canseco-Márquez & Gutiérrez-Mayén 2010).

Phyllodactylus ngiwa is reportedly highly efficient at regulating its temperature during both the day and night, allowing it to successfully exploit available active sites at night and refuges during the day ( Lara-Reséndiz et al. 2013).

Figures

FIGURE 9. Different views of the P. ngiwa sp. nov. preserved holotype (MZFC-HE 37273). Top body views: left dorsal view, right ventral view. Bottom head views: left lateral view, right dorsal view. (Photos by Israel Solano Zabaleta).

FIGURE 10. Phyllodactylus ngiwa sp. nov. holotype (MZFC-HE 37273) collected in San Juan Bautista Cuicatlan, Oaxaca. (Photo by Daniel Duran Arceo).

FIGURE 11. Two P. ngiwa sp. nov. individuals photographed during their nocturnal activity period. Their color pattern allows them to blend in with the rocky habitats of the Tehuacan Valley, Puebla. (Photos by Daniel Duran Arceo).

FIGURE 12. Distribution map showing the occurrence of individuals belonging to three species according to the findings of this study: P. ngiwa sp. nov. in red; Phyllodactylus sp., the Huautla-Morelos lineage in green; and P. bordai in blue. Protected areas are shown in yellow: the Tehuacan-Cuicatlan Biosphere Reserve (RBTC), located between Puebla and Oaxaca states, and the Sierra de Huautla Biosphere Reserve (REBIOSH), located in the south of the Morelos state.

FIGURE 13. Landscape found in the vicinity of the Zapotitlan Salinas Botanical Garden, showing the natural habitat of P. ngiwa sp. nov. (Photo by Daniel Duran Arceo).