Head and leg morphology of Elongata Brongniart, 1893: 433 (Late carboniferous, Archaeorthoptera): phylogenetic and palaeoecological implications

The discovery of new specimens of the Late Carboniferous species elongata Brongniat, 1893: 433, belonging to the taxon Archaeorthoptera nom. Béthoux and Nel, 2002, dis.-typ. Béthoux, 2007c (i.e. is more closely related to the Linnaean order Orthoptera than to any other recent insect order) is reported. The head and leg morphology of the species could be investigated thanks to the good preservation of the specimens, and new preparation. The tarsus is 5-segmented, supporting the view that this state is plesiomorphic for orthopterans s. s. Morphology of mandibules indicates a carnivorous food-habit. Fore- and mid-leg femora and tibiae were provided with long and spaced out spines, most probably arranged in two rows. These spines might have assisted the entrapment of preys. The relative length of leg segments, and the length of antennae, are reminiscent of the condition exhibited by phasmidans, suggesting a similar locomotion behavior.