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| Calamaria flavicollaris Aksornneam, Rujirawan, Yodthong, Pawangkhanant, Sung & Aowphol, 2026 Photographed by Parinya Pawangkhanant |
Abstract
A new species of Calamaria is described from the Tenasserim Range, Ratchaburi Province, western Thailand based on morphological and molecular evidence. Calamaria flavicollaris sp. nov. can be distinguished from its congeners by the combination of the following morphological characters: 1) rostral scale wider than high; 2) portion of rostral scale visible from above greater than the half the length of the prefrontal suture; 3) prefrontal length shorter than frontal length, not entering orbit and in contact with first two supralabials; 4) five or six scales surrounding paraparietal scale; 5) preocular and postocular present; 6) four supralabials, the second and third in contact with the eyes; 7) eye diameter smaller than eye-mouth distance; 8) five infralabials, the first pair separating the mental scale from anterior chin shields; 9) seven modified maxillary teeth; 10) 180 ventral scales with three preventral scales; 11) 13 divided subcaudal scales; 12) cloacal plate single; 13) tail relatively short (4.5% of the total length), tapering, gradually to a pointed tail tip; 14) dorsum dark brown with eleven dark longitudinal stripes; 15) ventral surface yellow with a median line of dark flecks on underside of tail; and 16) dark collar followed by yellow ring at nuchal region. Genetically, the new species exhibits a pairwise distance of ≥17.56% from all other congeners based on the mitochondrial cytochrome b gene fragment. Furthermore, we provide cranial osteological description of the new species based on micro-CT scanning. Calamaria flavicollaris sp. nov. is currently known only from the type locality and represents the fourth species of the genus recorded for Thailand.
Keywords: cranial osteology; herpetofauna; Isthmus of Kra; molecular; reed snake; Southeast Asia
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| Holotype of Calamaria flavicollaris sp. nov. (ZMKU R 01131) in life. A small figure shows the yellow color on the ventral side of this species Photographed by Parinya Pawangkhanant |
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| Head of Calamaria flavicollaris sp. nov. (ZMKU R 01131). A–B lateral view C–D dorsal view E–F ventral view |
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| Holotype of Calamaria flavicollaris sp. nov. (ZMKU R 01131) in preservative. A dorsal view B ventral view C lateral view at the midbody D dorsal view of tail E ventral view of tail |
Calamaria flavicollaris sp. nov.
Diagnosis. Calamaria flavicollaris sp. nov. can be distinguished from all other congeners by the following combination of characters (Tables 3, 4; Suppl. Table 1): 1) rostral scale wider than high; 2) portion of rostral scale visible from above greater than the half the length of the prefrontal suture; 3) prefrontal length shorter than frontal length, not entering orbit, and in contact first two supralabials; 4) five or six scales surrounding the paraparietal scale; 5) preocular and postocular present; 6) four supralabials, the second and third in contact the eyes; 7) eye diameter smaller than eye-mouth distance; 8) five infralabials, the first pair separating the mental scale from anterior chin shields; 9) seven modified maxillary teeth; 10) 180 ventral scales with three preventral scales; 11) 13 divided subcaudal scales; 12) cloacal plate single; 13) tail relatively short (4.5% of the total length), tapering, gradually to a pointed tail tip; 14) dorsum dark brown with eleven dark longitudinal stripes; 15) ventral surface yellow with a median line of dark flecks on underside of tail; and 16) a dark nuchal collar followed by a yellow ring along neck.
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| Four Calamaria species in Thailand: A Calamaria flavicollaris sp. nov. from Suan Phueng District, Ratchaburi Province B C. lumbricoidea from Than To District, Yala Province C C. schlegeli from Betong District, Yala Province D C. pavimentata from Kaeng Hang Maeo District, Chanthaburi Province Photos by Parinya Pawangkhanant (A–C) and Attapol Rujirawan (D) |
Etymology. The specific epithet flavicollaris is derived from the Latin words “flavo” (yellow), “collare” (collar or neck), and the suffix “-aris”, which refers to the appearance of the yellow nuchal ring of this species.
We suggested an English common name “Tenasserim Collared Reed Snake” and the Thai common name “งูพงอ้อบ่วงบาศ” (Ngu Phong O Buang Bat) for this species.
Akrachai Aksornneam, Attapol Rujirawan, Siriporn Yodthong, Parinya Pawangkhanant, Yik-Hei Sung, and Anchalee Aowphol. 2026. Integrative Taxonomy reveals A New Species of Calamaria (Squamata: Calamariidae) from the Tenasserim Range, Western Thailand. Contributions to Zoology. 95(4); 366–410. DOI: doi.org/10.1163/18759866-bja10102 [22 Sep 2026]
งูพงอ้อหัวแดง Calamaria schlegeli;
งูพงอ้อหลากลาย Calamaria lumbricoidea;
งูพงอ้อท้องเหลือง Calamaria pavimentata