Chamalycaeus asaluensis (Godwin-Austen, 1914)

Fig. 6

Alycaeus asaluensis Godwin-Austen, 1914: 385–386, pl. 145 figs 2, 2a–b.

Alycaeus barowliensis Godwin-Austen, 1914: 352, pl. 141 fig. 4. Syn. nov.

Alycaeus crispatus var. – Godwin-Austen 1874: 93, pl. 4 fig. 2.

Alycaeus barowliensis – Gude 1921: 205.

Alycaeus (Dicharax) asaluensis – Gude 1921: 237.

Alycaeus (Alycaeus) burowliensis [sic] – Ramakrishna et al. 2010: 46.

Chamalycaeus (Dicharax) asaluensis – Ramakrishna et al. 2010: 56.

Dicharax asaluensis – Páll-Gergely et al. 2020: 54.

Dicharax (?) barowliensis – Páll-Gergely et al. 2020: 77.

Diagnosis

Differs from the congeners by the long R3 swelling having straight anterior part.

Type material examined

INDIA • 2 syntypes of A. asaluensis (Fig. 6A–E); Dihung, N. Cachar; Godwin-Austen coll.; NHMUK 1903.7.1.2636 • holotype of A. barowliensis (single shell mentioned in the original description: Fig. 6F– J); Barowli R. Durrang, Assam; Godwin-Austen coll.; NHMUK 1903.7.1.2723 .

Type localities

“Barowli River, Akha Hills, Durrang, Assam ” ( A. barowliensis); “Neuglo”, “Phulong” and “Dihung River, N. Cachar, north of Asalu” ( A. asaluensis).

Differential diagnosis

Dicharax aspidentatus Gittenberger, Choki Gyeltshen & Sherub Sherub, 2024 has a higher spire and larger distance between the inner and outer peristomes. Chamalycaeus crispatus (Godwin-Austen, 1871) has a constriction anterior to the R3 swelling, is glossier and less densely ribbed. Dicharax rugosus (Godwin-Austen, 1914) has a higher spire, a shorter R3 swelling and more strongly fringed peristome.

Remarks

Only the corroded holotype of A. barowliensis is known, which is very similar to C. asaluensis, but has a slightly more globose shell (and narrower umbilicus) and more widely-spaced ribs on R1. Nevertheless, given their geographic proximity and that all other traits are identical, these differences are best explained by intraspecific variability.

This species was included in the genus Dicharax due to the absence of spiral striation (Páll-Gergely et al. 2020). However, the shell shape and other characters agree with this species group, and therefore, it is reclassified in the genus Chamalycaeus .