Pronotum and labium morphology of Harposceles paradoxus Burmeister and Surutu dytiscoides MartÃnez. 42 H. paradoxus; anterior margin of pronotum. Box indicates the complete marginal bead 43 S. dytiscoides; anterior margin of pronotum. Box indicates the incomplete marginal bead 44 S. dytiscoides; apex of the mentum. Arrow indicates the deeply emarginate apex of the mentum 45 H. paradoxus; apex of the mentum.