Lamachodes Redtenbacher, 1908

Ho, Wai-Chun George, 2018, New taxa of Necrosciinae from Vietnam (Phasmatodea: Diapheromeridae), Zoological Systematics 43 (2), pp. 178-189 : 181

3.2 Lamachodes Redtenbacher, 1908

Lamachodes Redtenbacher, 1908: 482 . Type species: Lamachodes laevis Redtenbacher, 1908: 482 , by original designation.

Diagnosis. Medium-sized Necrosciinae. Body unarmed, sparsely and inconspicuously granulated; cylindrical, slender and elongate. Head oval. Vertex flat. Occiput gently convex. Antennae filiform and long. Pronotum rectangular. Mesonotum slender and elongate. Metanotum as long as median segment. Abdomen cylindrical. Anal segment emarginated posteriorly in both sexes. Female subgenital plate elongate, scoop-shaped, distinctly notched posteriorly, apex surpassing or not surpassing posterior margin of anal segment. Male poculum cup-shaped, tapering posteriorly, apex pointed. Cerci cylindrical. Legs unarmed. Profemora distinctly incurved basally. Tegmina and alae minute and scale-like. Egg oblong with rounded posterior pole, ventral surface not flattened.

Distribution. Vietnam.

Remarks. Lamachodes Redtenbacher, 1908 is similar to Asceles Redtenbacher, 1908 and Marmessoidea Brunner von Wattenwyl, 1893 , but can be separated by scale-like tegmina and alae in both sexes, elongate abdominal subgenital plate in female, broadly emarginated posterior margin of anal abdominal segment and posteriorly elongate poculum in male and oblong egg capsule lacking flattened ventral surface. The discovery of L. brocki sp. nov. not only contributes to the knowledge of male and egg structures, but also the geographical distribution pattern for the genus. Based on the current distributions of the genus, which is restricted to southern and central parts of Vietnam, potential distributions can be discovered in northern Vietnam and its neighbouring countries such as Laos, Cambodia and southwestern parts of China. Currently two species are recognised and all of them only occur in Vietnam. The male of L. laevis Redtenbacher, 1908 is unknown. A key to the species of genus is only provided for the females.

Key to females of Lamachodes Redtenbacher, 1908 .

1. Posterior apex of abdominal subgenital plate not reaching posterior margin of anal abdominal segment ............................................. .............................................................................................................................................................. L. laevis Redtenbacher, 1908 Posterior apex of abdominal subgenital plate distinctly surpassing posterior margin of anal abdominal segment..... L. brocki sp. nov.