Desmobathrinae Meyrick, 1886

Murillo-Ramos, Leidys, Brehm, Gunnar, Sihvonen, Pasi, Hausmann, Axel, Holm, Sille, Ghanavi, Hamid Reza, Õunap, Erki, Truuverk, Andro, Staude, Hermann, Friedrich, Egbert, Tammaru, Toomas & Wahlberg, Niklas, 2019, A comprehensive molecular phylogeny of Geometridae (Lepidoptera) with a focus on enigmatic small subfamilies, PeerJ 7, pp. 1-39 : 20

Desmobathrinae Meyrick, 1886

Taxa placed in Desmobathrinae were formerly recognized as Oenochrominae genera with slender appendages. Holloway (1996) revived Desmobathrinae from synonymy with Oenochrominae and divided it into the tribes Eumeleini and Desmobathrini .

Desmobathrinae species have a pantropical distribution and they apparently (still) lack recognized morphological apomorphies ( Holloway, 1996). Our phylogenetic analysis has questioned the monophyly of Desmobathrinae sensu Holloway because some species currently placed in Oenochrominae were embedded within the group (see also Sihvonen et al., 2011), and also the phylogenetic position of the tribe Eumeleini is unstable (see below). Desmobathrinae can be regarded as a monophyletic group after the transfer of Zanclopteryx , Nearcha and Racasta from Oenochrominae to Desmobathrinae , and the removal of Eumeleini ( Table 2). Desmobathrinae as circumscribed here are an independent lineage that is sister to all Geometridae except Sterrhinae , Larentiinae and Archiearinae .

The monobasic Eumeleini has had a dynamic taxonomic history: Eumelea was transferred from Oenochrominae s.l. to Desmobathrinae based on the pupal cremaster ( Holloway, 1996), whereas Beljaev (2008) pointed out that Eumelea could be a member of Geometrinae based on the skeleto-muscular structure of the male genitalia. Molecular studies ( Sihvonen et al., 2011, Ban et al., 2018) suggested that Eumelea was part of Oenochrominae s.str., but these findings were not well-supported and no formal taxonomic changes were proposed. Our analyses with IQTREE and RAxML recovered Eumeleini in two very different positions, either as sister to Geometrinae (SH-like = 93.6, UFBoot2 = 71) ( Figs. 4 and 5 ), or as sister of Plutodes in Ennominae (RBS = 60) (Data S3). The examination of morphological details suggests that the position as sister to Geometrinae is more plausible: hindwing vein M2 is present and tubular; anal margin of the hindwing is elongated; and large coremata originate from the saccus ( Holloway, 1994, our observations). The morphology of Eumelea is partly unusual, and for that reason we illustrate selected structures (Data S4), which include for instance the following: antennae and legs of both sexes are very long; forewing vein Sc (homology unclear) reaches wing margin; in male genitalia coremata are extremely large and branched; uncus is crossshaped (cruciform); tegumen is narrow and it extends ventrally beyond the point of articulation with vinculum; saccus arms are extremely long, looped; and vesica is with lateral rows of cornuti. However, the green geoverdin pigment concentration of Eumelea is low in comparison to Geometrinae ( Cook et al., 1994). We tentatively conclude that Eumelea is probably indeed associated with Geometrinae . However, since eleven genetic markers were not sufficient to clarify the phylogenetic affinities of Eumelea , we provisionally place the genus as incertae sedis ( Table 2).

Figures

Figure 4 Phylogenetic relationships of the subfamilies Archierinae, Desmobathrinae, Epidesmiinae subfam. nov., Oenochrominae. Numbers above branches are SH-aLRT support (%)/ultrafast bootstrap support, UFBoot2(%), for nodes to the right of the numbers. Values of SH ≥ 80 and UFBoot2 ≥ 95 indicate well-supported clades (Trifinopoulos & Minh, 2018). Taxonomic changes are indicated by a symobolized arrow>. *Formal taxonomic treatment will be dealt with in P. Sihvonen et al., 2019, unpublished data. Full-size DOI: 10.7717/peerj.7386/fig-4

Figure 5 Evolutionary relationships of the subfamily Geometrinae. Numbers above branches are SH-aLRT support (%)/ultrafast bootstrap support, UFBoot2(%), for nodes to the right of the numbers. Values of SH ≥ 80 and UFBoot2 ≥ 95 indicate well-supported clades (Trifinopoulos & Minh, 2018). Taxonomic changes are indicated by a symobolized arrow>. § New subfamily. Full-size DOI: 10.7717/peerj.7386/fig-5