Cycloryx tenellus (Godwin-Austen, 1914)

Fig. 20J–N

Alycaeus (Cycloryx) tenellus Godwin-Austen, 1914: 417, pl. 155 figs 3–4, 4a.

Alycaeus (Cycloryx) tenellus – Gude 1921: 285.

Pincerna tenella – Páll-Gergely et al. 2020: 183.

Diagnosis

A species with somewhat questionable status (see Remarks). The only known shell is characterized by a somewhat conical-ovoid shell, smooth initial whorls, widely-spaced ribbing in the lower whorls and thin peristome.

Type material examined

MYANMAR • holotype (single shell mentioned in the original description: Fig. 20J–N); Shan Hills, in the same slide as N. 22; Fedden leg.; NHMUK 1906.5.5.87 .

Type locality

“ Shan States”.

Remarks

It is larger than any known species in this group. It is most similar to C. constrictus but has weaker ribbing (upper whorls smooth, although the holotype is strongly corroded). The more obvious separation between the inner and outer peristomes of this species compared to the figured syntype of C. constrictus is not a stable character, because in the other available lot of C. constrictus (NHMUK 1906.4.4.41) there are shells with similar peristome to that of the holotype of C. tenellus . A single shell is known of this species and very few of C. constrictus . If more material becomes available, it may happen that C. tenellus will be moved to the synonymy of C. constrictus .