Mnesilochus Stål, 1877

Hennemann, Frank H., 2021, Stick insects of Sulawesi, Peleng and the Sula Islands, Indonesia- a review including checklists of species and descriptions of new taxa (Insecta: Phasmatodea), Zootaxa 5073 (1), pp. 1-189 : 41

Genus Mnesilochus Stål, 1877

( Figs. 17–18 )

Type-species: Mnesilochus capreolus Stål, 1877: 39 , by subsequent designation of Kirby, 1904: 320.

Comments: This genus is distributed in Borneo, Palawan and the Philippines and the author is aware of an as yet undescribed species that occurs on Sangihe Island north of Sulawesi. The two species here described are the first records of the genus from Sulawesi.

Mnesilochus has been removed from synonymy with Carausius Stål, 1875 and reinstated as a valid genus by Hennemann & Conle (2007: 66). These authors and Seow-Choen (2016: 279) have attempted a clear separation from the very similar Hermagoras Stål, 1875 but morphological characters in the insects are scarce and merely include whether the mesosternum is keeled medio-longitudinally ( Hermagoras ) or not ( Mnesilochus ) and whether the eggs are round to ovoid with a rounded polar area ( Hermagoras ) or more or less laterally compressed and have a polar mound ( Mnesilochus ). The distinction presented by Seow-Choen (2016: 279) includes an erroneous character and thus deserves clarification. In addition to the morphology of the mesosternum, the author stated in the key to Bornean genera of Lonchodinae : Lonchodinae “ Postero-dorsal carina of profemur curved forwards, lamellate and may be foliaceous covering totally or partially antero-dorsal carina which is generally straight ” for Hermagoras and “ Postero-dorsal carina of profemor nut usually lobes ” for Mnesilochus ( Seow-Choen, 2016: 279) . This distinction does not hold true because Seow-Choen misinterpreted the anterodorsal carina as the posterodorsal carina and the anteroventral carina as the anterodorsal carina. Actually, the morphology of the profemur is basically identical in these two genera and remarkable in that the medioventral carina is very prominently developed, lamellate and strongly displaced towards the interior/anterior, resulting in that the anteroventral carina is strongly shifted inwards and upwards and notably approaches the anterodorsal carina. The anterodorsal carina (not the posteroventral carina as wrongly stated by Seow-Choen) is much expanded, lamellate and curved forwards to partly or completely cover the anteroventral carina in dorsal aspect. The posterodorsal carina in fact is very indistinct and not raised at all, being low and merely represented as an obtuse keel or ridge.

Figures

FIGURE 17. Mnesilochus bodiense n. sp. ♂, holotype [MNHU]: A. Habitus dorsal view; B. Habitus, dorso-lateral view; C. Terminal abdominal segments seen laterally.

FIGURE 18. Mnesilochus luwuense n. sp. ♀, holotype [NHMB]: A. Habitus, dorsal view; B. Habitus, dorso-lateral view; C. Habitus lateral view; D. Right mid leg in postero-lateral aspect; E. Lateral view of terminal abdominal segments; F. Dorsal view of terminal abdominal segments.