THE COMPLEXITY OF THE Apostolepis dimidiata GROUP, WITH PARTITION IN TWO GROUPS (SERPENTES: DIPSADIDAE: XENODONTINAE: ELAPOMORPHINI)

The species of Apostolepis located in the dimidiata group are heterogeneous, only justified by the projection of snout. The comparison of species located allowed the isolation of the small species from central-western Brazil, Bolivia, and Paraguay in a new group ambinigra. The new group differs from dimidiata main by having three infralabials contacting anterior chin-shields (vs. four), five supralabials (vs. six), five or six infralabials (vs. seven), background color brown or red (vs. red), with five stripes or none (vs. two), venter immaculate white (vs. blotched or immaculate), and very small size (vs. medium to large). The new group comprises the species: A. ambinigra, A. breviceps, A. christineae, A. intermedia, A. roncadori, and A. vittata; it occurs on central-western Brazil to Bolivia and Paraguay, Cerrado biome