Ligyra, Newman, 1841

Márquez-Acero, Ángela Sabrina, Lambkin, Christine L. & Lamas, Carlos José Einicker, 2021, Cladistic analysis of Ligyra sensu lato (Diptera: Bombyliidae), with description of a new genus, Zoological Journal of the Linnean Society 191 : -

Ligyra

Lambkin et al. (2003) distinguished the Australian Ligyra s.s. as a monophyletic group, separate from their new genus Euligyra . When we included the New World taxa in our analysis, they were found not to form a clade with the Australian Ligyra s.l., but rather with the genera Hyperalonia and Euligyra . Rather than merging these genera in Ligyra , we opt here for separating this clade into a separate genus, rather than expanding Ligyra to encompass the entire clade. Our choice is based on the hypothesis presented by Lamas & Nihei (2007) when studying the biogeography of Crocidiinae that, in Bombyliidae , the main lineages are supposed to have arisen and irradiated in the Middle Jurassic and the vicariant events that affect biogeography at the generic level seems to be related to the sequential separation of a Laurasian clade from a Gondwanan clade followed by the splitting of the latter on smaller components.

The species Lig. bombyliformis and Lig. punctipennis belong to Ligyra s.s. and continue to establish a clade well-supported by the characters vein i -r 1 sinuous (74: 3), large basal endplate of the spermathecal complex (182: 3) and gonocoxae with slight basal projection of the ventral ridge (136: 1), shared only with Eu. sisyphus (Fabricius, 1805) .

On the other hand, the species Lig. sinuatifascia and Lig. satyrus appear as polyphyletic sisters to the group formed by the genera Hyperalonia , Euligyra and Nyia . As discussed in Lambkin et al. (2003), Lig. bombyliformis , Lig. punctipennis , Lig. sinuatifascia and Lig. satyrus represent three different species-groups of the Australian Ligyra . Ligyra satyrus , in particular, is also found in south-east Asia, and suggestions are that examination of the Asian fauna may show that the group is also Oriental. Bowden (1971) suggested that the Australian Lig. satyrus and Lig. doryca (Boisduval, 1835) may be part of a group that invaded Australia in recent times.

The male genitalia of Lig. satyrus , Lig. bombyliformis and Lig. punctipennis are similar to that of Euligyra . In contrast, the male genitalia of Lig. sinuatifascia are different. The female genitalia of Lig. bombyliformis and Lig. punctipennis are more like those of Lig. sinuatifascia than Lig. satyrus , again showing strong links to Euligyra (Lambkin et al., 2003) . In the analysis of Lambkin et al. (2003), it was observed that, although Lig. sinuatifascia and Lig. satyrus presented with a mixture of characters, they formed an independent and well-supported group in Ligyra . However, the position of these two species, inferred by this study, suggests a review of all 22 Australian species and the Asian fauna is needed to clarify the generic limits.

Hyperalonia is a Neotropical genus. As in Lambkin et al. (2003), the rare Hyperalonia morio was the only species of this genus included in our analysis. In Lambkin et al. (2003), Hyperalonia was sister to a monophyletic Euligyra but in our results, Hyp. morio renders Euligyra paraphyletic.

The sister-group relationship between Hyperalonia + Euligyra and Nyia is supported by ten homoplasious characters, most of them belonging to external morphology, mainly characters related to wing venation. Several of these characters served in Lambkin et al. (2003) to distinguish Ligyra s.s. from Euligyra . In fact, the inclusion of the New World fauna into the analysis infers that Hyperalonia , Euligyra and Nyia are more closely related to each other than they are to the Australasian Ligyra .

Despite the apparent relationship between Hyperalonia , Euligyra and Nyia , we identified 17 characters in Hyperalonia that do not appear in any Ligyra s.l.; for example, the length of proboscis more than length of the head (18: 2), the length of basal stylomere less than or equal to the pedicel (31: 1), the midfemoral spines are absent (53: 0), the length of the anterior arms of aedeagal sheath are equal to the length of the the gonostylus (165: 1), the basal endplate of the spermathecal complex is absent (182: 0) and the apical endplate of the spermathecal complex is large (189: 0). Regardless of its close relationship with Euligyra , these character states should be considered as strong evidence of the validity of Hyperalonia as a separate genus. The inclusion of more species of Hyperalonia in a cladistic analysis is necessary in order to make further taxonomic decisions.

Euligyra and Hyperalonia form a clade supported by occipital foveal depression absent (14: 1) and gonocoxal ventral division fused entirely in a line (133: 1), except in Eu. paris (Bezzi, 1923) ( Fig. 2) (Supporting Information, Appendix S2). Unlike Lambkin et al. (2003), in our results Hyperalonia is sister to Eu. mars and Eu. enderleini (Paramonov, 1929) , rendering the genus Euligyra paraphyletic ( Fig. 1A). These three species are the only ones in Ligyra s.l with the length from the antennae to compound eye longer than length of scape (7: 1), and fore femoral spines shorter than width of femur (46: 1), except for Lig. punctipennis .

In the second clade of Euligyra , Eu. sisyphus , Eu. monacha and Eu. paris have pectinate macrochaetae on the collar surrounding the head, the anepisternum, laterotergite and, laterally, on abdominal tergite 1 (34: 2, 36: 3, 39: 3, 110: 2), unlike the remaining Ligyra s.l. in which the macrochaetae have a midstyle. Our topology suggests Hyperalonia might be considered to be the senior synonym of Euligyra (Afrotropical clade) but, as mentioned above, since we only have one of the five Hyperalonia species included in the matrix, no formal taxonomic changes will be made here.