Chamalycaeus (?) armillatus (Benson, 1856)

Pall-Gergely, Barna, Sajan, Sheikh, Tripathy, Basudev, Meng, Kaibaryer, Asami, Takahiro & Ablett, Jonathan D., 2020, Genus-level revision of the Alycaeidae (Gastropoda, Cyclophoroidea), with an annotated species catalogue, ZooKeys 981, pp. 1-220 : 1

Chamalycaeus (?) armillatus (Benson, 1856)

Alycaeus armillatus Benson, 1856: 227.

Alycaeus armillatus - Reeve 1878: pl. 5, species 38; Godwin-Austen 1914: 406, pl. 151, figs 3, 3a.

Alycaeus (Dicharax) armillatus - Kobelt 1902: 365; Gude 1921: 236-237.

Type locality.

"ad Thyet-Mio cum præcedente (= A. sculptilis)".

Material examined.

UMZC 102995 (holotype [single specimen mentioned in the original description]).

Remarks.

Protoconch low, no spiral striation visible.

The specimen largely matches Benson’s original description, and therefore we consider it to be the holotype. The photographs of that specimen show some signs of spiral striation. However, those striae may be part of the lower shell layers, and not raised threads as in other Chamalycaeus species. Consequently, the spiral striae on the holotype of A. armillatus may not be homologous with the ones in Chamalycaeus species; we would need fresh shells to confirm this. For the time being, we refer to this species as Chamalycaeus (?) armillatus .

The shells labelled as A. armillatus in the NHM (Thayet-myo, Pegu, coll. Blanford, NHMUK 1906.4.4.71, 6 shells) belong to another (probably undescribed) Chamalycaeus species based on the shorter R3, the shallower constriction between R2 and R3, and the smaller distance between the inner and outer peristomes.