Rediscovery and first record of the Phantasma Tree Snake , Imantodes phantasma Myers , 1982 ( Serpentes , Colubridae ) , in Colombia

We report the first record in Colombia, and the first find since 1966 of Imantodes phantasma Myers, 1982, based on 3 specimens from Unguía municipality, department of Chocó, Colombia. The present record adds a new snake species to the country’s list and extends this species’ documented distribution by approximately 65 km, in a straight-line northeast from its nearest previously known Panamanian locality. This is the first report of this species for more than 50 years since its description.


Introduction
The widespread Neotropical genus Imantodes Duméril, 1853 is composed of 8 species, distributed from Mexico to northern Argentina, through Colombia, with an exclusively continental distribution (Köhler 2008, Missassi and Prudente 2015, Uetz et al. 2017).They are a group of primarily arboreal and nocturnal snakes that inhabit rainforest, mid-montane forest or dry forest (Peters and Orejas-Miranda 1970, Myers 1982, Torres-Carvajal et al. 2012), from lowlands to uplands (up to 2300 m above sea level; Rojas-Morales et al. 2014).They sometimes occur in sympatry with congeners (Myers 1982).
Imantodes phantasma Myers, 1982 is known only from 2 male specimens, collected by Charles W. Myers and Tomas Quintero between 20-24 January 1966, in a montane cloud forest on the southeastern slope of Cerro Cituro, a peak on the northern end of the Serrania de Pirre, Province of Darien, Republic of Panama (Fig. 1), between 1030-1100 m (Myers 1982).Myers (1982) also said that he searched unsuccessfully for this species on the surrounding mountain formations of Serrania del Sapo, Cordillera de Juradó, and Serrania del Darién.The species has been categorized as Data Deficient by the IUCN Red List of Threatened Species (Ibáñez et al. 2013), because of the small number of specimens deposited at collections (only 2).Hence, there is scarce information about its ecology and current threats.Here, we report the first record of Imantodes phantasma from Colombia.

Methods
A field survey was carried out in rural area Unguía municipality, department of Chocó, Colombia by means of active searching method.The specimens were euthanized using 2% Xylocaine, fixed in 10% formalin, preserved in 70% ethanol, and tissue samples for DNA analysis were taken.Specimens were deposited at the reptile collection of the Instituto de Ciencias Naturales, Universidad Nacional de Colombia, Bogotá, Colombia, under the catalogue numbers ICN-R 12800, 12801, and 12830.Specimen identification was verified by R.A. Moreno-Arias and J.D. Lynch, and through comparison with images of the paratype AMNH-R 109493.The specimens
We collected 3 female adults of I. phantasma (Fig. 2) between 19:30-23:10 h, in a field survey using active searching sampling.These specimens were found on woody vegetation up to 170 cm above ground level, near a creek, in a rainforest with a dense closed canopy exceeding 30 m in height (Fig. 3).The understory where the snakes were found consists of palms, Arecaceae (Euterpe precatoria, Oenocarpus mapora, Socratea exhorriza, Dyctiocaryum lamarckianum), and arboreal species of the families Elaeocarpaceae (Sloanea sp.), Rubiaceae (Faramea sp., Psychotria sp. and Bathysa sp.), Melastomataceae and Lauraceae, among others.The ground was 90% covered by a thick layer of leaf litter, up to 40 cm in some locations.
Identification.Myers (1982) diagnosed Imantodes phantasma by dorsal color pattern, yellowish brown with black flecks and dorsal saddles on a light orangish brown body (Fig. 4); dorsal scales in 17-17-17 or 17-17-15 rows; vertebral scales about 2 times the width of midlateral scales and with concave or truncate rear margins; and other meristic characters that match with the collected specimens (Table 1).All characters agree with the original descriptions of Panamanian individuals, except for size, which may be due to sexual dimorphism (King 1989, Shine et al. 1999), since this species was described from 2 adult males and we collected 3 adult females.According to Cope (1866), Smith (1942), Zweiffel (1959), Myers (1982), Torres-Carvajal et al. (2012) and Missassi and Prudente (2015) (Table 2), in comparison with the other species of Imantodes (characters in parentheses), this species differs from I. cenchoa, I. gemmistratus, I. lentiferus and I. tenuissimus in its dorsal pattern of very light blotches, which are not sharply defined (vs dark and well defined dorsal blotches with shape of wide saddle); from I. gemmistratus by having 11-12 infralabials (vs 9-10), everted hemipenis equal to 6 subcaudals (vs 5); from I. tenuissimus by having 9 supralabials (vs 8); from I. inornatus by vertebral pattern of very light saddles or blotches (rather than fuzzy dark crossbands), 232-238 ventrals and 152-161 subcaudals (vs 196-218 ventrals and 108-132 subcaudals); from I. lentiferus by having 17 dorsal scale rows anteriorly and at midbody (vs 15-15); from I. chocoensis by the presence of loreal (vs the absence of loreal); and from I. guane by having 152-161 subcaudals (vs 147-148), by the absence of a dark pigmentation on temporal region (vs presence of a dark brown temporal stripe), dorsum of head orangish brown mottled with grayish brown (vs light brown with dark brown blotches), and the absence of expanded area on the distal portion of the sulcus spermaticus (expanded area present).Myers (1982); I. gemmistratus from Zweifel (1959) and Myers (1982); I. tenuissimus from Cope (1866) and Smith (1942); I. phantasma from Myers (1982) and this study.Because of the small range (<5000 km 2 ), few locations (>5) and threats to habitats (deforestation), we recommend a change to Endangered using the IUCN criteria B1ab(iii).This is the first record of this species since 1966, 51 years after its description.The possible reason for this is the absence of explorations in the Serrania del Darién, specifically, in the Cerro Tacarcuna, a mountainous formation within the Serrania, considered as a center of endemism and high biological uniqueness (Hernández et al. 1992, WWF 2008).Lack of explorations in the area might be due to difficulty in access, as well as the recently ended Colombian armed conflict.
The presence of I. phantasma in Colombia supports the ecosystems continuity on the Serrania del Darien, where the climatological, physiographic and landscape composition show particular conditions for the establishment of areas of endemism for biota (Myers 1969, Hernández et al. 1992).Also, its presence may be due to the biogeography of the mountain rainforests of the Serranía del Darién (Myers 1969, Myers andLynch 1997).Threats to this species include habitat loss and fragmentation, as a result from changes in land use by agriculture, logging, and illegal mining, activities that are increasing and ascending on the altitudinal gradient from the foothills of Cerro Tacarcuna, as a result of the expansion in the colonization of this area.

Figure 1 .
Figure 1.Distribution map of Imantodes phantasma.The yellow spots indicate previous records for the species in Panama (Myers 1982).The red stars indicate the localities where the specimens were found at the Cerro Tacarcuna, Unguía municipality, department of Chocó, Colombia.

Figure 3 .
Figure 3. Vegetation type of the habitat where specimens of Imantodes phantasma were recorded at the Cerro Tacarcuna, Unguía municipality, department of Chocó, Colombia.Photographs GCA.

Figure 4 .
Figure 4. Comparison of the dorsal color pattern between the AMNH-R 109493 (paratype; left) and ICN-R 12801 (in life; right).Photographs: paratype David A. Kizirian and Lauren Vonnahme, and specimen in life GCA.
Myers (1982)ed under the institutional permission of the IIAP (Decreto No. 1376 de 2013).Locality records for other specimens of I. phantasma were obtained fromMyers (1982).
EASS: expanded area on the distal portion of the sulcus spermaticus.** HL: hemipenis length of everted organs in relation to the number of subcaudals. *