Description
Ichthyophis cardamomensis is an unstriped Indochinese caecilian described from three females with total length ranges from 183.0 - 321.7 mm. From the dorsal view, the species has a flattened head that slightly broadens from the tentacles to the first collar. In the lateral view, the head tapers slightly between the first collar and the nares before becoming bluntly rounded at the snout. The snout barely projects over the nearly terminal mouth. The lips have straight edges with the corner of the mouth being placed closer to the throat than towards the dorsal side of the head. The teeth are small, recurved, and bicuspid, having a main cusp that is twice as long as the accessory cusp. The number of maxillary teeth between collected specimens ranges from 23 to 38, and 28 to 29 vomeropalatine teeth. The specimens had between 20 and 34 denary teeth, and between 19 and 22 inner mandibular teeth. The vomeroplante and inner mandibular series are smaller than the teeth in the premaxillary-maxillary and the dentary series. The vomeroplantine row is one quarter longer than the length of the premaxillary-maxillary tooth row. The dentary row is twice as long as the inner mandibular row. The palate is highly arched. The choane is oval, surrounded by a swollen margin of palatal skin, and located just posterior to the tentacles. The tongue is triangular and has a medial depression on the posterior two-thirds that is flanked on the anterior sides by round patches of glandular skin. The oval nares are closer to the top of the head than the upper lip but are barely visible from the dorsal view and cannot be seen from the ventral view. The eyes are subcutaneous; they form discs slightly elevated from the surrounding skin and are located closer to the top of the head than to the upper lip. The sensory tentacle is closer to the eye and upper lip then the nostrils. The aperture of the tentacle forms an area of elevated skin akin to the eyes, however, the aperture is smaller than the eyes; it’s much closer in size to the nostrils. At the corners of the mouth, there is a triangular depression of gular skin. The gular region appears flattened from the ventral view and has a median depressed groove that extends from the tentacles to a distinct groove of the first collar which in turn fades into the second collar (Geissler et al. 2014).

The collars are wider and deeper than the head and the body. The second collar is longer than the first in the ventral view. Both collars grooves are incomplete, visible from the ventral view, and curve slightly towards the head. The first collar groove is indistinct in the middle of the dorsum but still visible from the dorsal view on the outer edges of the dorsum. The second collar groove disappears on the ventral halves of the flanks and is not visible in the dorsal view. There is a slight depression on the ventrum at the anterior midline. The nuchal region sits just anterior to the first annular groove. The specimens discovered have between 322 and 364 annuli along their backs. Of these, only 60 annuli near the tail extend across both the belly and back. Those grooves that do cross the belly do so in a straight line before the cloacal disc interrupts them. The grooves on the dorsum form a double-S shape along the vertebral line. The species has 120 vertebrae. Small, oval scales are found on the posterior half of the annuli positioned in a single row in each scale pocket. The cloacal slit is longitudinal and interrupts six aunnuli. It is found on a triangular cloacal disc with five denticulations on the right and six on the left. There are between four and five annuli after the cloacal disc. The species does not have a true tail, instead the body tapers at the tail end with a nipple-like tail cap. The last annular groove does not cross the ventrum (Geissler et al. 2014).

Ichthyophis cardamomensis differs from other unstriped Indochinese caecilians in several ways including eye size, snout projection, location of tentacle, number of inner mandibular teeth, scale location, number of annuli, and number of vertebrate. More specifically, I. cardamomensis has larger eyes than I. acuminatus but smaller eyes and a larger snout projection than I. chaloensis. The tentacle of Ichthyophis cardamomensis is located closer to the nares when compared to I. catlocensis but closer to the eyes when compared to I. javanicus. Ichthyophis cardamomensis has a greater number of inner mandibular teeth than I. billitonensis, I. lakimi, I. larutensis, and I. weberi. It differs from I. bombayensis, I. dulitensis, I. laosensis, I. singaporensis, I. monochrous and I. sumatranus in the fact that I. cardamomensis does not have scales on the front half of its body. It differs from I. acuminatus, I. monochrous, I. orthoplicatus, and I. sikkimensis by having more annuli. And it differs from I. acuminatus, I. glandulosus and I. youngorum by having more vertebrate (Geissler et al. 2014).

In the preservative, I. cardamomensis has a blackish grey dorsal coloration and a lighter grey ventral coloration. The cloacal disc and terminal cap are whitish. There are also whitish margins around the eyes, tentacles, and nares. In life, I. cardamomensis has a uniform pinkish hazelnut brown coloration that brightens on its sides and belly. The lips, nostrils, and tentacles are whitish pink. The annular coloration is darker than the anular grooves (Geissler et al. 2014).

Among the specimens found, there was variation in the number of annuli and tooth count from the original holotype. However, the coloration, the shape of the annuli, scales missing from the front side of the body, a single scale row at the tail end of the body, and the presence of two rounded patches of glandular skin found on the tongue was consistent with the holotype (Geissler et al. 2014).

Distribution and Habitat

Country distribution from AmphibiaWeb's database: Cambodia

View distribution map in BerkeleyMapper.

Ichthyophis cardamomensis is native to southwest Cambodia, specifically the Cardamom mountains in Pursat Province. Due to the small number of specimens found, distribution and habitat may not be conclusively determined, however all specimens were found in the Phnom Samkos Wildlife Sanctuary. The holotype was found in a damp forest on a hillside at an elevation of 986 m. The forest was situated near a rocky stream with rapid water currents. The paratypes were found in a pitfall trap and along a rotting log in a hilly forest at an elevation of 528 m (Geissler et al. 2014). Caecilians, in general, exist predominantly in tropical and subtropical climates, in damper environments.

Life History, Abundance, Activity, and Special Behaviors
Very little is known about the life history, abundance, activities, or special behaviors of I. cardamomensis. Based off of where the specimens were found, we can infer that they prefer higher elevations and associate with small bodies of water (Geissler et al. 2014).

Trends and Threats
Due to limited information, a conservation status is premature. No trends or threats have been observed as of yet of I. cardamomensis (Geissler et al. 2014).

Comments
The species authority is: Geissler, P., Poyarkov Jr, N.A., Grismer, L., Nguyen, T. Q., An, H.T., Neang, T., Kupfer, A., Ziegler, T., Böhme, W., Müller, H. (2015). “New Ichthyophis species from Indochina (Gymnophiona, Ichthyophiidae): 1. The unstriped forms with descriptions of three new species and the redescriptions of I. acuminatus Taylor, 1960, I. youngorum Taylor, 1960 and I. laosensis Taylor, 1969.” Organisms Diversity and Evolution, 15, 143-174.

Ichthyophis cardamomensis is part of the Ichthyophis genus, a group of caecilians native to Indochina. Based on Maximum Likelihood, Maximum Parsimony, and Bayesian Inference analyses on 660 base pairs of COI and 1296 base pairs of cyt b, I. cardamomensis is most closely related to I. nguyenorum. Together, I. cardamomensis and I. nguyenorum are sister to a clade consisting of I. bannaincus and an unnamed Ichthyophis species (Geissler et al. 2014).

Ichthyophis cardamomensis gets its specific epithet from the area where it was found, the Cardamom region (Geissler et al. 2014).

Historically, the Indochinese caecilians have been organized by the presence or absence of a lateral stripe along the body of the caecilian; this is now being questioned as they believe that the lateral stripe is a homoplasy that has reoccurred in different, not closely related lines. Ichthyophis cardamomensis (which is unstriped) and its sister species, I. nguyenorum (which is striped), are interesting examples of this (Geissler et al. 2014).

References

Geissler, P., Poyarkov Jr, N.A., Grismer, L., Nguyen, T. Q., An, H.T., Neang, T., Kupfer, A., Ziegler, T., Böhme, W., Müller, H. (2015). ''New Ichthyophis species from Indochina (Gymnophiona, Ichthyophiidae): 1. The unstriped forms with descriptions of three new species and the redescriptions of I. acuminatus Taylor, 1960, I. youngorum Taylor, 1960 and I. laosensisOrganisms Diversity and Evolution, 15, 143-174.

Species Account Citation: AmphibiaWeb 2017 Ichthyophis cardamomensis <https://amphibiaweb.org/species/8301> University of California, Berkeley, CA, USA. Accessed Nov 21, 2024.

Citation: AmphibiaWeb. 2024. <https://amphibiaweb.org> University of California, Berkeley, CA, USA. Accessed 21 Nov 2024.

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