Pachybrachini

Gómez-Zurita, Jesús & Cardoso, Anabela, 2021, Molecular systematics, higher-rank classification and Gondwanan origins of Cryptocephalinae leaf beetles, Zoologica Scripta 50 (5), pp. 592-615 : 605

4.3.3 | Pachybrachini

The tribe Pachybrachini assembles some 700 species in eight genera, after excluding Mylassa , distributed in the Palaearctic, Afrotropical and Oriental regions, but particularly diverse in America ( Chamorro, 2013, 2014a; Watts, 2005). Several morphological traits are considered synapomorphies of the group, but they generally require assuming losses and reversals in different genera, weakening the recognition of the assemblage as a natural group ( Chamorro, 2013; Reid, 1990). Reid (1990) was the first to propose treating this lineage separately from Cryptocephalini and ranking it as a tribe, warning that “ Pachybrachini have always been placed in the Cryptocephalini , basically on the premise that they lack the distinguishing characters of Clytrini or Chlamisini ” (p. 188 in Reid, 1990). Our results, based on the study of three Neotropical and one Holarctic genus, fully support this view. It is early to extract conclusions from our limited sample, but based on the obtained tree topologies, it is possible to derive some interesting hypotheses such as the origin of western Palaearctic Pachybrachis , represented in our sample by two subgenera ( Chloropachys and Pachybrachis ), being a modern group derived from a primitive American stock.