Chamalycaeus sculpturus ( Godwin-Austen, 1875 )

Chamalycaeus sculpturus ( Godwin-Austen, 1875)

Figs 14–16

Alycaeus sculpturus Godwin-Austen 1875: 8 View in CoL , pl. 4 fig. 2.

Alycaeus crispatus var. makarsae Godwin-Austen, 1914: 372 View in CoL , pl. 158 fig. 13. Syn. nov.

Alycaeus ( Alycaeus) sculpturus View in CoL – Kobelt 1902: 351. — Ramakrishna et al. 2010: 51.

Alycaeus sculpturus View in CoL – Godwin-Austen 1914: 398–399, pl. 145 figs 6, 6a–b. — Gude 1921: 218. Alycaeus ( Dicharax) crispatus var. makarsae View in CoL – Gude 1921: 243.

Dicharax (?) sculpturus View in CoL – Páll-Gergely et al. 2020: 103 View Cited Treatment .

Dicharax (?) crispatus View in CoL makarsae – Páll-Gergely et al. 2020: 83 View Cited Treatment .

Type material examined

INDIA • 1 syntype of A. sculpturus ( Fig. 14A–E); Sikhami, NE Munipur; NHMUK 1903.7 About NHMUK .1.2666 • 4 syntypes of A. sculpturus ( Fig. 14F–J); Mungching, Munipur; NHMUK 1903.7 About NHMUK .1.2667 • 8 syntypes of A. crispatus var. makarsae ( Fig. 14K–O); Makarsa, Khasi; Godwin-Austen leg.; NHMUK 1903.7 About NHMUK .1.2638 .

Additional material examined

INDIA – Mizoram • 1 empty shell ( Fig. 15); Blue Mountain, Lawngtlai district ; 22.727° N, 93.135° E; 1400 m a.s.l.; 27 Jan. 2019; N.A. Aravind leg.; Ar 68; NZSI LM1720 View Materials GoogleMaps • 1 empty shell; same data as for preceding; Ar61; NZSI LM1721 View Materials GoogleMaps • 2 complete shells ( Fig. 16) + 2 broken shells; same data as for preceding; Ar74; NZSI LM1722 View Materials GoogleMaps .

Type localities

“on the hill ranges from near Tellizo Peak to the eastward, and on Mungching Hill in Munipur” ( A. sculpturus ); “Makarsa, N. Khasi Hills (or more correct, Maokarsa; the common Khasi prefix “Mao” meaning a stone)” ( A. crispatus var. makarsae ).

Remarks

The type specimens of A. sculpturus and A. crispatus var. makarsae show no notable differences; therefore, the latter is a junior synonym of the former. The specimens collected in the Blue Mountain ( Figs 15–16) are slightly smaller than typical C. sculpturus and A. crispatus var. makarsae shells and have multiple tiny knobs along the peristome but otherwise are very similar to those species. These knobs are probably homologous with the tips of triangle-shaped structures (termed chevrons in Gittenberger et al. 2024) in the aperture of typical C. sculpturus shells and many other alycaeine species (i.e., two tiny knobs of one shell are homologous with the two tips of a single triangle in the other). A similar case was observed in a Chinese species; typical Dicharax fimbriatus ( Bavay & Dautzenberg, 1912) shells had triangular thickenings along the peristome, while its synonym, Chamalycaeus plicilabris multidentatus Yen, 1939 , had multiple tiny knobs along the peristome (Páll-Gergely et al. 2017).

This species was included in the genus Dicharax due to the absence of spiral striation ( Páll-Gergely et al. 2020). However, re-examination of the syntypes of A. sculpturus and Alycaeus crispatus var. makarsae revealed some spiral striation on the teleoconch.