Chamalycaeus buaboke Pall-Gergely & A. Reischutz 2021
- Dataset
- Nineteen new species of Alycaeidae from Myanmar and Thailand (Gastropoda: Caenogastropoda: Cyclophoroidea)
- Rank
- SPECIES
- Published in
- Páll-Gergely, Barna, Hunyadi, András, Grego, Jozef, Reischütz, Alexander, Auffenberg, Kurt (2021): Nineteen new species of Alycaeidae from Myanmar and Thailand (Gastropoda: Caenogastropoda: Cyclophoroidea). Zootaxa 4973 (1): 1-61, DOI: 10.11646/zootaxa.4973.1.1
Classification
- kingdom
- Animalia
- phylum
- Mollusca
- class
- Gastropoda
- order
- Architaenioglossa
- family
- Cyclophoridae
- genus
- Chamalycaeus
- species
- Chamalycaeus buaboke
description
Description. Shell off-white, probably somewhat translucent when fresh; shell outline oval in dorsal view; spire slightly elevated, low conical; body whorl rounded; protoconch low, finely granular, spiral striae lacking, 1.25 – 1.5 whorls; R 1 of 1.25 – 1.5 whorls, with strong, elevated, slim, densely, regularly arranged ribs, fine spiral striation between ribs; boundary between R 1 and R 2 distinct due to change of rib density; R 2 ribs slightly curved towards aperture, spaces between ribs approximately as wide or slightly wider than ribs; ca. 26 ribs present; R 2 + R 3 less than quarter whorl (ca. 80 ˚), R 2 somewhat shorter than R 3; boundary between R 2 and R 3 distinct due to deep constriction and ribless posterior portion of R 3; R 3 with short, narrow, ribbed central swelling; anterior slope of swelling steeper than posterior slope; aperture oblique to shell axis, rounded with small basal incision; boundary between inner and outer peristomes conspicuous, inner peristome strongly thickened, protruding, and slightly expanded; outer peristome thin, strongly expanded, distinctly reflected portion over umbilicus; distance between inner and outer peristomes significant, swelling of R 3 and edge of outer peristome closely situated; umbilicus relatively narrow, ca. one fourth of shell width. Measurements. D: 2.03 – 2.29 mm, H: 1.23 – 1.33 mm. Operculum. Unknown.
description
Figs 1 A, 2
diagnosis
Diagnosis. A tiny Chamalycaeus species with finely ribbed R 1, elevated, narrow swelling on R 3, and great distance between inner and outer peristomes.
diagnosis
Differential diagnosis. The most similar species is Chamalycaeus canaliculatus (Möllendorff, 1894) (examined material: Golf von Siam: Koh-Samui, coll. Möllendorff, SMF 109468, lectotype, Fig. 1 B), which was described from the nearby island, Koh Samui. The new species from Wua Talap Island is slightly smaller (C. canaliculatus D: 2.4 mm), has a more elevated R 3, and much greater distance between the inner and outer peristomes. The new species differs from Dicharax ovatus n. sp. by the slightly smaller size, lower spire, very rounded body whorl and aperture, blunt swelling on R 3, and the shorter distance between the inner and outer peristomes.
distribution
Distribution. This new species is known only from the type locality (Fig. 3).
etymology
Etymology. The specific epithet (noun used in apposition) derives from the name of the cave where the new species was collected.
materials_examined
Material examined. Holotype: Thailand, Surat Thani Province, Ang Thong Islands, Wua Talap Island, ascent to Buaboke Cave, 9 ° 37.993 ’ N, 99 ° 40.369 ’ E, ca. 50 m a. s. l. (locality code: Th 1), Sep. 2007, A. Reischütz leg., at base of limestone rocks, NHMW 113484 (D: 2.03 mm, H: 1.23 mm). Paratype: 1 shell, same data as holotype, RE.