Systematic and taxonomic revision of Emerald and Tigertail dragonflies (Anisoptera: Synthemistidae & Corduliidae)

Libelluloidea is the most speciose superfamily within dragonflies
(Odonata: Anisoptera), yet intrafamilial relationships have remained
contested for the past 150 years. Here we present a phylogenetic
hypothesis for two families within Libelluloidea, Corduliidae (Emeralds),
and Synthemistidae (Tigertails) based on comprehensive taxon sampling
(Corduliidae: 141/165 species, Synthemistidae: 123/150) for which we
generated Anchored Hybrid Enrichment (AHE) high-throughput molecular
sequences (10 - 1054 loci). Furthermore, we combined our molecular dataset
with 100 discrete morphological characters based on wing, body, nymphal
and genitalic characters. Using our molecular data, and an evaluation of
morphological characters via ancestral character state reconstruction, we
propose a new classification for these taxa.  Here, three new
families are erected: Lauromacromiidae fam. nov.,; Macromidiidae fam.
nov.,; Aeschnosomatidae fam. nov.. and the status is revised for six
families: Pseudocorduliidae stat. rev., Lohmann, 1996; Gomphomacromiidae
stat. rev., Tillyard & Fraser, 1940; Austrocorduliidae stat. rev.,
Lohmann, 1996; Idomacromiidae stat. rev., Tillyard & Fraser 1940;
Idionychidae stat. rev., Tillyard & Fraser, 1940; Neophyidae stat.
rev., Tillyard & Fraser, 1940. Furthermore, we sink the genus
Procordulia Martin, 1907 into the genus Hemicordulia Selys, 1870. Finally,
we recover five enigmatic taxa (Archaeophya Fraser, 1959, Libellulosoma
Martin, 1907, Austrophya Tillyard, 1909, Apocordulia Watson ,1980, and
Cordulisantosia Fleck and Costa, 2007) for which no molecular data was
previously available within these new families with high support using a
total-evidence approach. Character state reconstructions revealed
widespread homology among traditional characters used to identify groups
within each family. We estimate the ancestral Libelluloidea possessed a
compact anal loop, prominent uniform labial dentition in the nymphs, and a
reduced ovipositor. Finally, time-divergence analyses estimate
Libelluloidea to have originated within the Late Jurassic, with subsequent
families diversifying throughout the Cenozoic.