Morphological and genetic characterization of a new Armadillidium species (Oniscidea, Armadillidiidae) from Tunisia

Armadillidium boukorninense n. sp., a new species collected in northeastern Tunisia, is described. This species can be easily recognised by the tegument structure, the morphology of the cephalon and the high differentiation of the male pereopod 7. Its geographical distribution is limited to the northeast of Tunisia, in the maquis and garrigues habitats of sub-humid and semi-arid areas. This new species is morphologically similar to A. decorum. However, the morphological comparison between these two species showed a divergence at the cephalon, hind margin of pereon-epimeron 1, pereopod VII and pleotelson. An allozyme analysis of ten enzymatic systems (ME, PHI, EST, MPI, ACPH, GOT, IDH, PEP, PGM, MDH) confirmed this morphological differentiation. Among the eighteen loci that were analysed, differentiation in six diagnostic (Mpi, Pgm, Me, Acph-2, Pep-3, Got-2) and two partially-diagnostic loci (Idh-1, Phi),were easily recognized. Furthermore, high values of Nei's genetic distance (Nei, 1978) (D¯=0.69±0.1) and FST=0.72 indicated a high genetic differentiation of these two species. When taking into account these two approaches, A. boukorninense n. sp. is morphologically and genetically different from A. decorum.