Phylogenetic relationships of family groups in Pentatomoidea based on morphology and DNA sequences (Insecta: Heteroptera) Author Grazia, Jocelia Department of Zoology, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil jocelia@ufrgs.br Author Schuh, Randall T. Division of Invertebrate Zoology, American Museum of Natural History, New York, NY 10024, USA Author Wheeler, Ward C. Division of Invertebrate Zoology, American Museum of Natural History, New York, NY 10024, USA text Cladistics 2008 2008-11-21 24 932 976 journal article 10.1111/j.1096-0031.2008.00224.x e89a8dfa-e923-4a01-97f4-4edd4a0b8db0 3968591 UROSTYLIDIDAE Dallas , sensu stricto Historical: The systematic position of this family has been ambiguous over time, as was stressed by Schuh and Slater (1995) . Singh-Pruthi (1925) related it to the Acanthosomatidae . Yang (1938a ,b, 1939 ) and Pendergrast (1957) related it to the Pyrrhocoridae , and Miyamoto (1961) to the Pentatomidae . Kumar (1971) believed that the group represented an early divergence from the other pentatomomorphans, possibly together with the Pyrrhocoridae , with which they share uniquely the fused 2nd valvifers that form an M- or W-shaped sclerite. As Gapud (1991) did not provide an illustration of what he considered as separate 2nd valvifers, we conclude that he erroneously interpreted the 2nd valvifers in the species of Urostylididae that he studied. Berger et al. (2001) proposed the emended spelling Urostylididae , in order to remove the homonymy between the heteropteran family name and Urostylidae Bütschli (Ciliophora, Hypotrichia). Analytical result: The treatment of the Urostylididae as the basal grouping within the Pentatomoidea by Gapud (1991) is a position supported by our morphological analyses ( Figs 42–44 ) and combined analyses under an unweighted equal costs regime ( Figs 51 and 53 ). Under unequal costs, Urochela is dissociated from Urostylus and moved up to a more central position within the pentatomoid cladogram. Characters supporting the treatment of the Urostylididae sensu strico as the sister group of all remaining Pentatomoidea are listed below in the Conclusions. The monophyly of the Urostylididae sensu strico is recognized in our analysis by the presence of a stridulitrum on A 1 in the hind wing ( 221 ) and the presence of bristles on the claws ( 311 ). Additionally, gonocoxites 9 (in females) form an Mor W-shaped sclerite ( 465 ; Fig. 28 ), which we suggest argues for its treatment at the family level.