Aphalaridae Low 1879

Family * Aphalaridae Löw, 1879

In both mtg trees, Aphalaridae contains six strongly supported monophyla which we rank as subfamilies: Aphalarinae, Microphyllurinae subfam. nov., Phacopteroninae Heslop-Harrison, 1958 stat. nov., Rhinocolinae Vondráček, 1957, Spondyliaspidinae Schwarz, 1898 and a clade of seven undescribed species from New Caledonia representing an unnamed genus and subfamily. This last subfamily is not further treated here and will be described in another paper (Percy, unpublished). There is evidence (from multiple molecular analyses) that these six subfamilies are likely not collectively monophyletic, however, there is still insufficient data to clarify the phylogenetic placement of each monophyletic subfamily with respect to the others, and therefore, rather than recognize each as a separate family, we have retained them as subfamilies within Aphalaridae “sensu lato” pending further analyses. In Aphalaridae, we also place Togepsyllinae Bekker-Migdisova, 1973 and Cecidopsyllinae Li, 2011 stat. nov. which were not included in the molecular analyses by Percy et al. (2018) but representatives were analysed by Cho et al. (2019). A morphological character shared by all constituent subfamilies, and putative synapomorphy for the family, is the tarsal arolium of the immatures which is either completely absent or forms a lobe lacking an unguitractor (Burckhardt & Ouvrard 2012).

Apart from strong support of the sister group relationship of Microphyllurinae subfam. nov. (as “ Parapaurocephala ” in Percy et al. 2018) and Phacopteroninae stat. nov., there are no consistent and well-supported relationships between the subfamilies in the molecular analyses by Percy et al. (2018). A putative morphological synapomorphy grouping the Rhinocolinae, Spondyliaspidinae and Togepsyllinae is the tubercular or knob-like meracanthus rather than horn-shaped as in the other aphalarid subfamilies and most other Psylloidea. Luo et al. (2017) listed some putative synapomorphies suggesting a close relationship of Rhinocolinae and Togepsyllinae, a relationship which was also shown in Drohojowska’s (2015) trees based on an analysis of the thorax morphology, and recovered in the molecular data set of Cho et al. (2019).

Aphalaridae, in the present definition, differs from that of Burckhardt & Ouvrard (2012) in the positions of Cecidopsyllinae, Microphyllurinae subfam. nov., Pachypsyllinae and Phacopteroninae. Cecidopsylla Kieffer, 1905, was assigned to Calophyidae (Mastigimatinae) and is transferred here to Aphalaridae (Cecidopsyllinae). Microphyllurus Li, 2002, the only member of Microphyllurinae subfam. nov., was treated as a junior synonym of Peripsyllopsis Enderlein, 1926 (Liviidae: Euphyllurinae: Diaphorinini) by Burckhardt & Ouvrard (2012), whereas the “‘ Paurocephala ’ longicella group”, which we consider here a synonym of Microphyllurus (see below), was referred to Aphalaridae (Rhinocolinae). Pachypsyllinae was part of Aphalaridae and is transferred here to Carsidaridae. Phacopteroninae was considered a family of basal position within Psylloidea, and a basal position for Phacopteronidae as sister to the remaining Psylloidea was strongly supported in Cho et al. (2019); this is one of the notable differences with analyses in Percy et al. (2018). It may be that the different taxon sampling strategies were critical in determining these results, but here we have elected to adopt the placement using the more comprehensive taxon sampling in Percy et al. (2018).