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| Xenotorodor stygioxanthus Sterling, Lees & Grundy, 2023 DOI: 10.3897/nl.46.101457 |
Abstract
The family Lecithoceridae is not well represented in the Palaearctic region, with very few taxa in Europe. Here we describe a new genus and species of lecithocerid moth, Xenotorodor stygioxanthus Sterling, Lees & Grundy, gen. nov., sp. nov. The taxon represents a subfamily new to Europe. We consider placement of the genus within Crocanthinae or Torodorinae. We place it in Torodorinae, notwithstanding the reduced gnathos in the male genitalia. DNA barcodes suggest that the taxon belongs within a distal clade of this subfamily. They are over 9.2% pairwise divergent from any hitherto cleanly sequenced Lepidoptera taxon and over 10.1% from nearest taxonomically identified neighbours in Neighbor Joining and ML trees. Characteristics of the DNA barcode and morphology of this new taxon suggest that refinement of synapomorphies for the family and two subfamilies is needed. We have nearly 100 records for this new species since 2020, all from a small area of Southern Spain, close to the Straits of Gibraltar. The life history and early stages of the species are unknown.
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| Xenotorodor stygioxanthus gen. nov., sp. nov. 2. ♂ Holotype. 3. ♀ Paratype. 4. ♂ Habitus. 5. Male genitalia. 6. Aedeagus. 7. Pre-genital abdomen (5–7. ♂ holotype slide no. NHMUK014331156). 8. ♂ Holotype lateral image prior to mounting, gnathos indicated. 9. Wing venation slide no. NHMUK014331163. 10. ♂ Holotype, highly magnified section of antenna. 11. ♀ Paratype, female genitalia, slide no. NHMUK014331160. Scale bars: 5 mm (black); 0.5 mm (green). Figs 4, 8 and 10 not to scale. |
Xenotorodor Sterling, Lees & Grundy, gen. nov.
Xenotorodor stygioxanthus Sterling, Lees & Grundy, sp. nov.
Diagnosis: Forewings black with a purplish sheen, a narrow yellow bar from costa to dorsum before ½ and a yellow costal spot at ¾ (Figs 2–4), antenna and labial palps yellow, antenna of male thickened with rings of large yellow scales projecting outwards from base of each flagellomere (Fig. 10). R3, R4 and R5 of forewing with a common stalk. M2 present in forewing but absent in hindwing. M3, CuA1 and CuA2 of forewing with a common stalk, CuA1 and CuA2 stalked in forewing (Fig. 9). Male genitalia with small membranous gnathos and very small sclerotised mesial process (Figs 5, 8), vinculum semicircular, sclerotised and melanised (Fig. 5). Female genitalia with appendix bursae, corpus bursae small and rounded without signum (Fig. 11).
Etymology: Xenotorodor from xenos, gr., meaning, among other things, stranger or outsider. This is a reference to the unusual combination of morphological features for a species of Torodorinae in the new taxon, and the substantial geographical extension of the range of the subfamily. The gender of the genus name is male. The specific name stygioxanthus is from stygios, gr., meaning among other things extremely dark; and xanthos, gr., meaning yellow, a reference to the blackish forewings marked with yellow.
Conclusions:
It is noteworthy to detect a new subfamily for the European continent that is established in Spain. This interesting taxon from around Tarifa exhibits considerable morphological and genetic divergence from hitherto known or DNA barcoded taxa (between about 10 and 13% to its nearest phylogenetic neighbours, and more than 9.2% from nearest hits as regards sequences not compromised by ambiguity codes). Its placement was not straightforward. It is clearly a lecithocerid both on the basis of its morphology and its DNA barcode, and it appears to fall by phylogenetic analysis within Torodorinae rather than Crocanthinae, despite its reduced gnathos. Our placement in a new genus is by elimination and should spur other attempts to find its closest relatives. The work we have carried out in seeking to place the taxon shows that existing data is insufficient to show that Torodorinae and Crocanthinae are separate clades, with an expanded phylogenomic dataset clearly needed, and that the morphological synapomorphies supporting Lecithoceridae, Torodorinae and Crocanthinae need further refinement. Torodorinae is a subfamily which is widespread palaeotropically and we are unable to narrow the origin of X. stygioxanthus. Further field and taxonomic studies of this taxon and other Lepidoptera in adjacent parts of North Africa and Southern Spain are likely in our view to yield interesting results in terms of taxonomic diversity, relationships of the currently established fauna, and changes in populations as a result of changing climate conditions.
Mark J. Sterling, David C. Lees and Dave Grundy. 2023. Xenotorodor stygioxanthus gen. nov., sp. nov. (Lepidoptera, Lecithoceridae, Torodorinae), described from an established population in Spain with discussion of taxonomic placement. Nota Lepidopterologica. 46: 103-121. DOI: 10.3897/nl.46.101457
