Review of recent taxonomic changes to the emerald moths (Lepidoptera: Geometridae: Geometrinae)

Abstract Background The subfamily Geometrinae (Lepidoptera: Geometridae), commonly known as emerald moths, is an ecologically diverse group of moths with over 2,500 described species. Many taxonomic and phylogenetic studies of Geometrinae have been undertaken in the past decade, resulting in hundreds of new taxonomic changes since online publication of the most recent checklist in December 2007. New information This review synthesises the last 12 years of alpha-taxonomic research in Geometrinae. A comprehensive list of Geometrinae genus- and species-group descriptions, synonymies, combinations and other taxonomic changes, made since 2007, is provided. Since 2007, the known species richness of Geometrinae has increased from 2,529 to 2,642 species; an updated list of all these species is presented in a supplementary spreadsheet.


Introduction
The family Geometridae is an incredibly diverse lineage of moths that contains over 23,000 described species, making it the second-most speciose family in all of Lepidoptera Hausmann 2007, van Nieukerken et al. 2011). Although the subfamily Geometrinae only comprises roughly one-tenth of this species richness, it is one of the more recognisable geometrid subfamilies because of the green colouration found in most adults and some larvae. Geometrinae are consequently known as 'emerald moths' and have been the subjects of studies on phenotypic plasticity and polyphenism (Greene 1989, Canfield et al. 2008. Many authoritative taxonomic works on Geometrinae have been published over the years, but with many new species being described annually, it does not take long for an update to become necessary. Parsons et al. (1999) published a two-volume catalogue of the geometrid moths of the world, which is currently the most recently printed work that contains a comprehensive checklist of the global emerald moth fauna. However, between 1999 and 2007, one of this checklist's co-authors, Malcolm Scoble, worked with Axel Hausmann to update the checklist; these revisions are hosted on the Lepidoptera Barcode of Life website. At the time of the most recent update (December 2007), the online checklist contained 269 genera and 2,529 species of Geometrinae. Since then, hundreds of taxonomic changes have been made in this subfamily, including over 100 new species. In this review, we catalogue the last 12 years of emerald moth taxonomy and update the list of geometrines provided by Scoble and Hausmann (2007) to include all newly-described emerald moth species.

Materials and methods
Updates and changes to the online checklist of Geometrinae are presented in alphabetical order by genus, following the format used by Scoble and Hausmann (2007). Since their checklist was last updated in December 2007, the taxonomic literature published between January 2008 and December 2019, inclusive, was consulted. It was also found that some taxonomic works (e.g. Beljaev 2007) were published prior to December 2007, but were not incorporated into the update; these are consequently included in this review.
Within each genus section, valid species names are listed in alphabetical order, with junior synonyms placed on an indented line following the corresponding senior synonym. Only genus-and species-group taxonomic changes in Geometrinae are discussed here; a review of recent family-group taxonomic changes can be found in Ban et al. (2018) and , both of whom have also proposed new taxonomic changes to the geometrine tribes and subtribes, based on molecular phylogenetic data. Scoble and Hausmann (2007) did not include subspecies in their checklist, but post-2007 taxonomic changes to subspecies are discussed in this review.
The type of taxonomic change is indicated in parentheses. In this catalogue, the word 'new' and the abbreviation 'nov.' (novus, -a, -um) both denote that a taxonomic change was recent enough to not appear in the checklist of Scoble and Hausmann (2007). In this review, no taxonomic changes are proposed for the first time; this is further emphasised by the use of quotation marks surrounding each record of taxonomic change in the Results. Citations for recent taxonomic changes are provided in corresponding Remarks sections for each genus. The vast majority of taxonomic changes discussed here were proposed based solely on morphological evidence, such as variation in colour patterns, wing venation and genitalic characters of the adults. If molecular evidence were used to justify a taxonomic change, this is noted in the corresponding Remarks section.
If the status of a subspecies has been changed or a new synonymy has been proposed, the name of the associated valid species name is provided for context. Otherwise, species that have not undergone any taxonomic changes since the publication of Scoble and Hausmann (2007) are not included in the main text; a full list of all current Geometrinae species names is provided in the supplementary material. Similarly, synonyms that are not directly associated with a recent taxonomic change are excluded from the text.
Multiple Latin abbreviations for standard taxonomic terms are used throughout the text. Since the abbreviations themselves are not standardised across all taxonomic literature and do not appear at all in Scoble and Hausmann (2007), the notation used by Kitching et al. (2018) for a recent checklist of bombycoid moths was applied here in both the main text and supplementary material. These abbreviations and their definitions, are as follows: "comb. nov." -new combination "comb. rev." -revived combination "gen. nov." -new genus "nom. nov." -new replacement name "nom. nud." -nomen nudum (without description, thus unavailable) "sp. nov." -new species "ssp. nov." -new subspecies "stat. nov." -new status "stat. rev." -revived status "syn. nov." -new synonym "syn. rev." -revived synonym The subspecies Bathycolpodes subfuscata subferrata was elevated to the species B. subferrata by Karisch (2010). Hausmann & Parisi, 2014 ("sp. nov.") Notes: Nine new species were described , Hausmann et al. 2014. Müller et al. (2019) noted that Comibaena levequei may be identical to C. pseudoneriaria Wehrli, 1926, but tentatively accepted it as a distinct species. Comibaena delicatior was synonymised with C. nigromacularia by Han and Xue (2011a). Comibaena pictipennis superornataria had its status changed from subspecies to junior synonym of C. pictipennis by .

Nomenclature:
Epichrysodes tienmuensis Han & Stüning, 2007 ("sp. nov.") Notes: Epichrysodes is currently a monotypic genus containing only the type species, E. tienmuensis; both the genus and the species were described by . Haruchlora maesi Viidalepp & Lindt, 2014 ("sp. nov.") Notes: Haruchlora is currently a monotypic genus containing only the type species, H. maesi; both the genus and the species were described by . Han and Xue (2011a) created the new combination Jodis omeiensis, stating that this species was transferred from the genus Gelasma Warren, 1893; however, Gelasma had been designated a junior synonym of Maxates Moore, [1887] by Holloway (1996). Despite this synonymy, the combination Maxates omeiensis (Chu, 1981) does not appear to have ever been published between 1996 and 2011.

Nomenclature:
Loxochila burmensis (Han, Galsworthy & Xue, 2009)  Loxochila tibeta (Chu, 1982) ("comb. nov.") Notes: One new species was described (Han et al. 2009b). Loxochila was treated as a junior synonym of Geometra in Parsons et al. (1999) and Scoble and Hausmann (2007). Han et al. (2009b)retained this classification in their revision of Geometra, which divided the genus into two species groups. The type species of Loxochila, at the time named Geometra smaragdus (Butler), served as the eponymous taxon of the smaragdus species group. The molecular phylogeny of Ban et al. (2018) demonstrated that the smaragdus group is a strongly-supported clade that also contains one species from a different genus (Tanaorhinus kina Swinhoe). Ban et al. (2018) consequently reinstated the generic status of Loxochila and transferred the species in the smaragdus group, including T. kina, to this genus.

Other species affiliated with Geometrinae
Pseudobiston pinratanai Inoue, 1994 Notes: Pseudobiston pinratanai Inoue, 1994, was classified as a geometrine in Scoble and Hausmann (2007) but was recently transferred to the new family Pseudobistonidae by Rajaei et al. (2015).

Cerura melanoglypta (Lower, 1905)
Notes: One species in the Scoble and Hausmann (2007) checklist, Cerura melanoglypta (Lower, 1905), is classified as a geometrine (Ollerenshaw 2012), but has never formally been transferred from the notodontid genus Cerura Schrank, 1802. We agree that this species should eventually be assigned to a genus in Geometrinae, but it is technically not in Geometrinae at this time.

Discussion
In summation, nine new genera, 128 new species and ten new subspecies of emerald moths have been described since the publication of Scoble and Hausmann (2007), along with over 80 new genus-and species-group changes within subfamily Geometrinae. Since 2007, the known species richness of Geometrinae has increased by ~4.5%, from 2,529 species (Scoble and Hausmann 2007) to 2,643 species.
Brief description: This table provides a list of all new species descriptions, combinations and other taxonomic changes in the subfamily Geometrinae (Lepidoptera: Geometridae) since 2007 (Sheet 1: "Taxonomic changes since 2007"). This table also provides a list of the 2,643 current valid species names in the subfamily Geometrinae (Lepidoptera: Geometridae), with their authorship and year of description (Sheet 2: "All current Geometrinae species"). Download file (325.00 kb)