Phylogeny and biogeography of Thyridosmylus (Neuroptera: Osmylidae)

Abstract

The first phylogenetic analysis of the genus Thyridosmylus Krüger is presented. All species from China were scored in a morphological analysis, along with extralimital species from India (Thyridosmylus pustulatus Kimmins) and Madagascar (Thyridosmylus marmoratus Fraser), and were compared with out-group exemplars from Spilosmylus Kolbe, Thaumatosmylus Krüger and Osmylus Latreille. A monophyletic Thyridosmylus sister to Spilosmylus is confirmed based on this analysis, with the Malagasy Thyridosmylus marmoratus as sister to the Oriental Thyridosmylus species. Based on the results of this analysis, the biogeography of world Thyridosmylus is discussed. It is proposed that the genus originated in Gondwana no later than the Late Cretaceous (88 Ma) before the break-up of the Madagascar-India continent. A new species, Thyridosmylus paralangii sp.n., is described from Guangxi Province, whereas two species [Thyridosmylus langii (McLachlan) and Thyridosmylus perspicillaris minor Kimmins] are recorded from China for the first time. Four synonyms are identified: Thyridosmylus laetus Yang et al. syn.n., Thyridosmylus similaminor Yang syn.n., Thyridosmylus vulgatus Yang syn.n. and Thyridosmylus mimoroides Yang syn.n. A key to the species of the world is provided.

Revision of the genus Gryposmylus Krüger, 1913 (Neuroptera, Osmylidae) with a remarkable example of convergence in wing disruptive patterning

“…6), the structure of the female sclerites is also variable among subfamilies. The enlarged gonocoxite 9 (=gonopophyses lateralis) is closely associated anteriorly with gonopophysis 9 (=sternite 9 of Wang et al (2011)) in Protosmylinae, Spilosmylinae and Osmylinae and two separate sclerites are clearly visible. By contrast, in more derived subfamilies Porisminae, Kempyninae, Eidoporisminae and Stenosmylinae, gonopophyses 9 is not closely associated as a regular sclerite with gonocoxite 9, but instead is more elaborately shaped as a single articulating sclerite which acts upon sternite 8.…”

“…Terminology follows Tjeder (1957), Adams (1969) and Wang et al (2011) with the following modifications based of detailed examinations and a recent assessment of structural homology across all genera of Osmylidae and related families of Neuroptera (SLW, unpublished data). Figure 5 depicts the various male genitalic structures (colour-coded) typically exhibited in Protosmylinae.…”

Two new species of Thyridosmylus Krüger, 1913 from Madagascar (Neuroptera, Osmylidae)

“…The congeneric status of all species in the genus has been routinely accepted by subsequent authors (Wang et al 2008, 2011; Winterton et al 2017); in a cladistics analysis of Thyridosmylus , Wang et al (2011) concluded the Malagasy species occupy a sister position to the Oriental species, suggesting the southern origin of this genus should be no later than Late Cretaceous. Indeed, in their phylogenetic analyses of Osmylidae, Winterton et al (2017) deduced that the divergence of Thyridosmylus from its sister genus Spilosmylus Kolbe occurred during the Middle Jurassic (177 Mya), and that early splits in both genera were caused by vicariance resulting from the subsequent rafting of India.…”

“…Presently there are 19 species described in Thyridosmylus , including 17 species from South East Asia and two from Madagascar, suggesting the conspicuously disjunct geographical distribution (Gerstaecker 1884; Navás 1933; Kimmins 1942; Fraser 1955; Yang 1987, 1988, 1992, 1993, 1999, 2002; Yang et al 1995; Wang et al 2008, 2011). The congeneric status of all species in the genus has been routinely accepted by subsequent authors (Wang et al 2008, 2011; Winterton et al 2017); in a cladistics analysis of Thyridosmylus , Wang et al (2011) concluded the Malagasy species occupy a sister position to the Oriental species, suggesting the southern origin of this genus should be no later than Late Cretaceous.…”

New Philippine species of Spilosmylus Kolbe (Neuroptera, Osmylidae)

“…A close relationship between Protosmylinae and Spilosmylinae is supported by molecular data and by the presence of unique features in male and female genitalia, in particular the presence of a narrowly arching gonarcus (Winterton and Wang 2016; Winterton et al 2017). Spilosmylinae are recognizable due to the presence in the hind wing of a spur vein originating basal to the MP vein and of a basal sclerotised process on the mediuncus (Wang et al 2011; Winterton et al 2017). This group is by far the largest subfamily of osmylids, with at least 113 described species, although placed in only three genera: Thaumatosmylus Krüger (8 species), Thyridosmylus Krüger (20 species) and the most diverse genus of the family, Spilosmylus Kolbe (85 species).…”