Revalidation and redescription of three distinct species synonymized as Plagiometriona sahlbergi (Coleoptera: Chrysomelidae: Cassidinae)
Flinte Vivian, Viana Jéssica H., Macedo Margarete V., Windsor Donald, Sekerka Lukáš
Acta Entomologica Musei Nationalis Pragae 56(2): 743-754, 2016
Abstract: Plagiometriona sahlbergi (Boheman, 1855), P. multisignata (Boheman, 1855) and P.
scenica (Boheman, 1855) were described over a century and half ago as separate
species based on dry museum specimens. The latter two were later synonymized
with P. sahlbergi. While observations in nature find both P. sahlbergi and P.
multisignata co-occurring on the same host plant, subtle morphological
differences suggested they may be distinct species. We tested the validity of
the original species separation using additional morphological characters and
available molecular sequence data. The new evidence supports
Boheman’s original separation of species. Accordingly we remove P.
multisignata stat. restit. and P. scenica stat. restit. from synonymy with P.
sahlbergi and restore their species status. Mitochondrial gene sequence data
suggest that P. sahlbergi and P. multisignata bear a closer relationship to
other sympatric Plagiometriona species than they do to one another, raising the
possibility that these two species have convergent morphologies due to their
shared food plant. Biological and ecological notes are also given for these two
Key words: Coleoptera, Chrysomelidae, Cassidinae, Plagiometriona, synonymy, phylogeny, cytochrome oxidase I, morphology, Atlantic Forest, Brazil, Neotropical Region