Taxonomy | Erebidae | Lymantriinae | Nygmiini & "Euproctis"

This post stems from the auto id of many different (but externally similar looking) species attributed to
"Euproctis" taiwana

"Euproctis" taiwana from Taiwan (source: Taiwan Moth Information Center)

Unfortunately, "Euproctis" taiwana is restricted to Taiwan and the Ryukyu islands (Wang, H.Y., 1993; Guide Book to Insects in Taiwan 4 - Illustrations of Lymantriidae in Taiwan. Chu Hai Publishing (Taiwan) Co.. 118 pp., so all the observations outside this geographic area that have been attributed on iNaturalist (mostly by the auto-id suggestions) to this species will need to be re-assessed.

The old, Hampsonian, concept of Euproctis was reviewd by J.D.Holloway in his work on the moths of Borneo, wherein Euproctis was more strictly defined, with many species being placed in genera that had to that point been regarded as synonyms of Euproctis. The tribal grouping of Nygmiini now roughly equates to the Hampsonian concept of Euproctis. See paragraph 3 at https://www.mothsofborneo.com/part-5/nygmiini/nygmiini.php for a deeper dive. Where a species that used to be regarded as placed in Euproctis, but now of uncertain placement within Nygmiini, the genus name Euproctis is put into quotation marks to indicate that the species awaits formal placement in one of the many nygmiine genera. It is noted here that the Digital Moths of Asia website (under the Moths of Japan family of websites) uses the combination Orvasca taiwana

The upshot is that for photo observations of live moths that look roughly like "Euproctis" taiwana, it is not safe to place most observations even to genus (there are the genera Arna, Artaxa, Toxoproctis, Micromorphe, Orvasca, Somena, Bembina, Cozola, Medama and more to be considered from the tribe Nygmiini, as well as the more narrowly defined Euproctis.
By way of a species example, please take a look at the MoB entry for "Euproctis" wilemani.
"Euproctis" wilemani.
It is a little larger than taiwana but quite similarly patterned, and is in a morphologically distinct group separate from taiwana that is best identified through analysis (by dissection) of the reproductive morphology. Holloway notes, however, All these species are members of a large Oriental complex with similar forewing fasciation and male genitalia. so even with dissection, one must take great care to undertake objective and critical analysis.

One only needs to look at plates 5 through 9 of Moths of Borneo (part 5) to see the scope for confusion!

Moths of Borneo (part 5): Nygmiini
Plate 5 | Plate 6 | Plate 7 | Plate 8 | Plate 9

Posted on 30 June, 2024 09:33 by hkmoths hkmoths

Comments

some further publications that discuss the "Euproctis" issue....
Kemal, Kizilgdağ & Koçak, 2019, pp20-21

Chaos in the Phylogeny of the Genus Euproctis
In the presented study notshown phylogenetic tree 4 has indicated that also “traditional” Euproctis belong to taxonomically difficult assemblage. Phylogenetic relationships among species of this genus are the worst resolved part of the lepidopteran tree of life, having short internodes and many poorly statistically supported deeper nodes. This indicates that mtCOI gene per se is very likely insufficient to resolve the deep Heterocera phylogeny. Possibly, further loci can help to improve resolution within the Euproctis lineages. But another different molecular marker (COI, mt16S rRNA, EF-1 α, CAD, RpS5, MDH, GAPDH, GAPDH) did not bring distinctly better-supported Nygmiini phylogenies (Wang et al, 2015).
A promising solution to unravel the evolutionary history of the Euproctis could be the synergistic effect of increased molecular and morphological datasets from different geographical locations.
Congruence among many morphological and molecular characters implies a robust inference of phylogeny, whereas extensive conflict suggests that the phylogenetic history is not being faithfully recovered and that reassessment of the characters is necessary. In the notpresented phylogenetic tree, seen the diagnostic characters that identify the species in genus Euproctis cannot determine the boundaries of species.
In the phylogenetic tree, many Euproctis species are close to different taxa rather than with congeners, so Euproctis is a paraphyletic group. In this study, Euproctis sp3 is sister position with E. vitellina, morphologically not supported by synapomorphies. The same contradiction is also available between Euproctis sp1 and E. nigrofasciata. The genetic distance between Euproctis sp3 and E. vitellina is 2.34%, and the genetic distance between “Artaxa”?sp. and Euproctis nigrofasciata is 2.10%. These two populations appear to be distinct species, because they have greater genetic distances than the threshold of 2.00%. Likewise, the genetic distance between mtCOI sequence of the Somena scintillans population presented in this study with and the mtCO sequences of another population of this species obtained from the Boldsystems was 0.90%. In the phylogenetic analysis conducted in this study, mtCOI (658bp) molecular barcodes of E. nigrofasciata and E. vitellina species first time were obtained and the Euproctis sp4 population appeared to be distinct species. ...
In the study about Euproctis groups has made by Wang et al (2015), Euproctis remains extremely polyphyletic, and is in great need of a comprehensive revision many of the same problems relating to species boundaries and diagnostic characters. Thus supporting the assertion that the taxonomic problems highlighted here are likely to be persistent throughout Heterocera, and perhaps for Lepidoptera as a whole. At the Euproctis species, we uncovered inconsistencies in classification that are relatively easily addressed. The difficulty in dealing with Euproctis genera increases, as the majority of those species represented were not monophyletic.
Our results suggest that around half of the species richness of the genus is not formally recognized. This is because corresponds to discernible morphotypes that are as yet undescribed, and even cryptic species. The cryptic diversity or the revision of genus corresponds to presently synonymized/unused species names with nomenclatural priority, which will complicate future taxonomic work.
Additionally, further sampling from different geographically regions, will likely uncover a higher proportion of undescribed taxa. The assessment and formal description of the real species diversity of the Euproctis as a whole, will take a significant, and probably incalculable, amount of time and multidisciplinary efforts.
It is frequently a great challenge to distinguish between intra and inter-specific boundaries, because morphological convergence and plasticity blur our ability to perceive many taxonomic relationships. Our molecular work shows that many frequently employed characters/conditions are not particularly reliable for diagnosing a number of species. To resolve Lepidopteran systematics, traditionally sampling efforts and after that sequencing of DNA markers of taxa and populations represented are essential. In conjunction with molecular data, morphologic characters need to be re-inspected and contrasted with signal from molecular analyses in order to reform taxonomy and rewrite diagnoses. Nomination of topotypes directly associated with genetic data in situations of degraded or lost type specimens, is highly advisable in order to facilitate clarification of the taxonomy of these diverse, commonly encountered, ecologically important, and morphologically complex organisms.

Posted by hkmoths 3 months ago

Wang et al., 2015 is online at https://onlinelibrary.wiley.com/doi/full/10.1111/cla.12108

Their Figure 1 has all the Nygmiini grouped as a distinct clade, but "Euproctis" is all over the place therein.

Our results robustly recover the monophyly of the Nygmiini clade (PP = 1.00; BP = 99), but confirm that Euproctis and possibly Nygmia Hübner are polyphyletic groups. In Nygmiini, Albarracina Staudinger is the most basal taxon followed by the Bembina Walker + Lacida Walker pair in both model-based trees, but this trio is broken up in the parsimony consensus tree. Somena Walker + Kidokuga Kishida and Orvasca Walker + Sphrageidus Maes form a strongly supported clade (PP = 1.00; BP = 100; BS = 29). Arna Walker is a sister group to Artaxa Walker (PP = 1.00; BP = 99; BS = 28), with Euproctis kanshireia Wileman, E. cryptosticta Collenette and E. sp3 included in the latter genus (PP = 0.97; BS = 6).

Posted by hkmoths 3 months ago

Add a Comment

Sign In or Sign Up to add comments