Revision of the cockroach subfamily Blattinae based on morphological and molecular analyses

Blattidae Latreille is widely distributed worldwide and includes a variety
of sanitary pests, such as Periplaneta americana (Linnaeus), Periplaneta
australasiae (Fabricius), and Periplaneta fuliginosa (Serville). The
subfamily composition of Blattidae has undergone significant changes in
recent years, and a few long-standing controversies have been resolved.
However, the paraphyly of Blattinae Latreille, and the polyphyly of
Periplaneta Burmeister within the subfamily, remain unresolved. We
addressed these issues through phylogenetic analyses of the Blattinae
based on mitochondrial genomes and nuclear genes (18S and 28S), and
morphological analyses of nine male genital characters. Our study showed
that Dorylaea Stål and Nazgultaure Lucanãs are sister taxa and distantly
related to Blattinae. Periplaneta s.l. was found to be widely polyphyletic
across five or six separate clades, while Mimosilpha Bey-Bienko was
embedded within Homalosilpha Stål. Integrating ancestral character state
reconstruction (ASR) analyses, morphological character comparisons, and
our phylogenetic results, we propose five new genera (Unihamus Luo
& Wang, gen. nov.; Fortiblatta Luo & Wang, gen. nov.;
Arcicaulis Luo & Wang, gen. nov.; Tenumembrana Luo & Wang,
gen. nov.; Crescispina Luo & Wang, gen. nov.) to revise
Periplaneta s.l. We describe two new species (Hobbitoblatta semialata Luo
& Wang, sp. nov. and Crescispina qiaoi Luo & Wang, sp.
nov.). We treat Mimosilpha as the junior synonym of Homalosilpha. The ASR
analyses reveal the evolutionary status of genital characteristics in
Blattinae s.s., and suggest that the morphology of sclerites L4C, R1H and
R1G can be used as diagnostic characters for genera or subfamilies.