Parafimbrios vietnamensis, Ziegler & Ngo & Pham & Nguyen & Le & Nguyen, 2018

Ziegler, Thomas, Ngo, Hai Ngoc, Pham, Anh Van, Nguyen, Tham Thi, Le, Minh Duc & Nguyen, Truong Quang, 2018, A new species of Parafimbrios from northern Vietnam (Squamata: Xenodermatidae), Zootaxa 4527 (2), pp. 269-276 : 271-273

Parafimbrios vietnamensis sp. nov.

Figs. 2–3 .

Holotype. IEBR A.2018.7 (field number LC2016.8), male, collected by H.V. Tu and H.N. Ngo on 2 nd June 2016 near Hoang Ho Village, Phang So Lin Commune, Sin Ho District , Lai Chau Province (22 0 22.180’N, 103 0 14.485’E), at an elevation of 1,317 m above sea level.

Diagnosis. A species of the genus Parafimbrios , characterized by a combination of the following characters: 1) rostral laterally with two raised, curved edges; the upper one, together with a horizontal curved ridge of tissue, separate the rostral from the internasals; 2) nasal in contact zone with rostral with curved raised edge; 3) nasal in contact zone with supralabials each with two small oblique, curved raised edges located above first and second as well as above second and third supralabials; 4) suture between the internasals much longer than that between the prefrontals; 5) supralabials 8, with the first four bearing raised edges; 6) infralabials 7; mental and anterior three to four infralabials with raised edges; 7) temporals 4+4–5; 8) 35–33–29 dorsal scale rows; 9) laterally rounded ventrals 164; 10) unpaired subcaudals 49; 11) total length of at least 266 mm in males (with a tail length of 44 mm, and a TaL/TL ratio of 0.165).

Description of holotype. Total length 266 mm (snout-vent length 222 mm, tail length 44 mm); TaL/TL ratio 0.165; body slender, cylindrical; head length 7.2 mm (from tip of snout to hind margin of parietal); head not distinct from neck, dorsally covered with large shields; eye small, with vertically sub-elliptic pupil; right maxilla with ca. 27 small, curved, subequal teeth, progressively slightly enlarged posteriorly.

Rostral triangular, not visible from above; the sides of the rostral each with two raised, curved edges; the upper one, together with a horizontal curved ridge of tissue at the outermost front of the internasals separate the rostral from the internasals; suture between the internasals (1.7 mm) much longer than that between the prefrontals (0.7 mm); nostril in the anterior part of a large, concave nasal; nasal in contact zone with rostral with curved raised edge, extending from horizontal, curved ridge of tissue in front of each internasal to first supralabial; nasal in contact zone with supralabials each with two small oblique, curved raised edges located above first and second as well as above second and third supralabials; frontal slightly broader than long, rounded at both sides in front, much shorter than the parietals, from anterior tip subdivided in middle for most part (3/4) of its length; loreal large, heptagonal, extending from the nasal to the eye; one small preocular, at the upper front of eye; one supraocular, wider than high; two postoculars on both sides, the upper one hexagonal, being much larger, the lower one elongated, reaching somewhat below the eye; on the right side a very small third postocular, discernible, reaching somewhat above the eye; one large pentagonal to hexagonal subocular; four anterior and four (left) to five (right) posterior temporals each; eight supralabials, the first five very small, with the first four bearing raised edges, the last one much elongated; sixth and seventh supralabials in contact with the subocular; one mental, followed by seven infralabials; mental and anterior three to four infralabials with their raised edges; first pair of infralabials in contact with each other; first five infralabials in contact with the single pair of enlarged chin shields; chin shields covering nearly the whole of the chin in front, in contact with the first ventral; no posterior chin-shields.

Dorsal scales small, cycloid, keeled from region behind the neck onwards; 33 scale rows at midbody, every second of the outermost row distinctly enlarged; ca. 35 scales round the anterior part of the body, and 29 dorsal scale rows at posterior body; correspondence of two dorsal scale rows per ventral plate throughout the body; distinct, laterally rounded ventrals 164; single subcaudals 49, without tail tip; cloacal entire; tail moderate. The left hemipenis basally everted.

Coloration of holotype in preservation. The ethanol-preserved holotype brownish-black above, with broad yellow neck band widening towards the venter and stretching to the chin region; dorsal head surface in part reddish-brown, in particular in the middle of parietals and frontal; venter greyish-brown, lighter anteriorly, darker towards tail region; ventrals anteriorly and laterally darker.

Etymology. Analogous to the naming of the recent Parafimbrios discovery from Laos ( P. lao ) we name the new species from Vietnam after the country of origin.

Distribution. Parafimbrios vietnamensis sp. nov. currently is only known from the type locality in Lai Chau Province, Vietnam ( Fig. 4 ).

Natural history. The male holotype of Parafimbrios vietnamensis sp. nov. was discovered at 21:00 at an elevation of 1,317 m a.s.l. in a forest valley. It was drizzling at the time of capture with the air temperature at the site being 24 ° C and the relative humidity 85%. The surrounding habitat was disturbed limestone karst forest and fragmented with hill agricultural fields.

Figures

FIGURE 2. Head views of the holotype of Parafimbrios vietnamensis sp. nov. (IEBR A.2018.7) in preserved state. Phot. T. Ziegler.

FIGURE 3. Frontal view of head (top) and lateral view of midbody region (bottom) of the holotype of Parafimbrios vietnamensis sp. nov. (IEBR A.2018.7) in preserved state. Phot. T. Ziegler.

FIGURE 4. Map showing the type locality of Parafimbrios vietnamensis sp. nov. in Lai Chau Province, northwestern Vietnam (star) together with known records for P. lao (dots; after Teynié et al. 2015, Nguyen et al. 2015).