Dicharax crenatus (Godwin-Austen, 1871)

Fig. 34F–J

Alycaeus crenatus Godwin-Austen, 1871: 90–91, pl. 3 fig. 5.

Alycaeus crenatus – Godwin-Austen 1874: 150; 1914: 388–389, pl. 143 figs 8, 8a–b. — Sowerby 1877: pl. 1, species 1, figs a–b.

Alycaeus (Dicharax) crenatus – Kobelt 1902: 366. — Gude 1921: 241.

Chamalycaeus (Dicharax) crenatus – Ramakrishna et al. 2010: 57.

Dicharax crenatus – Páll-Gergely et al. 2020: 56.

Type material examined

INDIA • 2 syntypes (Fig. 34F–J); Mokarsa, Khasi Hills; Godwin-Austen coll.; NHMUK 1903.7.1.2642 .

Type locality

“On Burrail Range, N. Cachar, at ca 5000 feet ”.

Differential diagnosis

Dicharax daflaensis has a smooth R2, while D. crenatus possesses curved R2 ribs. Moreover, the R3 swelling of D. daflaensis is more conical, i.e., less abruptly elevating. Dicharax tangmaiensis has a more strongly undulated inner peristome, and a smooth R2 surface. While in D. crenatus the R2 and R3 are of comparable length, in D. davisi and D. ochraceus the R3 is much longer than the R2.

Remarks

In the original description, Godwin-Austen (1871) gave “Burrail Range, N. Cachar” as the type locality. Later (Godwin-Austen 1914: 389) explained that he found two shells in his collection (from Mokarsa in the NW Khasi Hills, no. 2642), based on which the drawings of A. crenatus were made in the original description (Godwin-Austen 1871), but their locality was not mentioned in the original description. Based on ICZN Art. 72.4.1.1, the two shells from Mokarsa are also part of the type series. Even if Godwin-Austen referred to one of the shells as “the type shell” (Godwin-Austen 1914: 389), this does not constitute a valid lectotype designation (Art 74.5), because the condition of “unambiguousity” has not been met (we do not know which of the two shells were selected to be “the type”).

Godwin-Austen (1874) noted that “ A. crenatus was found as far east as Shiroifurar, also at Kezakenomih and Yémai”. Those samples were not examined by us.