Subfamily * Psyllinae Latreille, 1807

Arytainini Crawford, 1914: 106.

Alloeoneurini Vondráček, 1951: 127.

Anomoneurini Klimaszewski, 1963: 92.

Cyamophilini Loginova, 1976: 596.

Cacopsyllinae Li, 2011: 744.

Cornopsyllinae Li, 2011: 532. Syn. nov.

Comments

In both trees, the monophyly of Psyllinae and the division into three monophyletic subgroups is very strongly supported. The most basal clade consists of a single Asian species, viz. Cacopsylla eriobotryae (Yang, 1984). The second clade contains four West Palaearctic genera associated with faboid Fabaceae: Arytaina Foerster, 1848, Arytainilla Loginova, 1972, Arytinnis Percy, 2003 and Livilla Curtis, 1835. The first three are monophyletic, the last is paraphyletic with respect to Arytainilla and Arytinnis, as previously shown by Percy (2003). Livilla ulicis Curtis, 1836, the type species of Livilla, belongs to a very strongly supported clade which is sister group to a poorly supported Arytainilla. Livilla blandula (Horváth, 1905), a species closely related to Livilla pyrenaea (Mink, 1859), the type species of Floria Löw, 1879, and Livilla radiata (Foerster, 1848), the type species of Alloeoneura Löw, 1879, belong to a clade which is sister group to the very strongly supported Arytinnis. To split Livilla s. lat. into two monophyletic genera, viz. Livilla s. str. and Floria (syn. Alloeoneura), respectively, is not practicable at the moment as only a quarter of the known species (see Ouvrard 2020 for a complete list of species) were included in the molecular analyses and no morphological characters are known reflecting these groupings. The third clade comprises a very strongly supported group of North American species associated with Ceanothus L. (Rhamnaceae) (= Ceanothia Heslop-Harrison, 1961 and Nyctiphalerus Bliven, 1955, see Table 2), previously referred to the genera Ceanothia, Euglyptoneura Heslop- Harrison, 1961 and Nyctiphalerus, which is sister group to a poorly supported clade comprising one clade represented by a single species (Pexopsylla cercocarpi Jensen, 1957) and four very strongly supported clades: 1. holarctic species of Cacopsylla Ossiannilsson, 1970 associated with Elaeagnaceae, Lardizabalaceae, Rosaceae and Salicaceae (= Cacopsylla s. str.); 2. holarctic species associated with Betulaceae (= Psylla s. str., Table 3), previously referred to Baeopelma Enderlein, 1926, Cacopsylla, Chamaepsylla Ossiannilsson, 1970 and Psylla; 3. palaearctic species associated with Buxus (Buxaceae) (= Spanioneura Foerster, 1848, see Table 4), previously referred to Psylla and Spanioneura; 4. North American species associated with Cercocarpus and Purshia (Rosaceae) (= Purshivora Heslop-Harrison, 1961, see Table 2), previously referred to Cacopsylla, Ceanothia, Nyctiphalerus and Purshivora. Cho et al. (2019) transferred Psylla longicauda Konovalova, 1986, an Asian species associated with Prunus, to Spanioneura and provided morphological adult characters to define Psylla s.str. and Spanioneura.

Similar to Arytaina, Arytainilla, Arytinnis and Livilla, associated with brooms (Fabaceae), which constitute a species-rich clade endemic to the Western Palaearctic, a group of Psyllinae radiated in Western North America on Ceanothus (Rhamnaceae) as well as Cercocarpus and Purshia (Rosaceae). North America authors (Crawford 1914; Tuthill 1943b; Jensen 1956, 1957a, 1957b; Bliven 1956, 1958) assigned these species to the genera Arytaina, Euphalerus and Psylla, rendering these genera very artificial, and to two monotypic genera Nyctiphalerus and Pexopsylla. Heslop-Harrison (1961) discussed the North American genera previously referred to Arytaina and, rightly, concluded that they are not congeneric with Arytaina spartii (Hartig, 1841) (= A. genistae (Latreille, 1804)), the type species of Arytaina. He erected the four genera Amorphicola Heslop-Harrison, 1961, Ceanothia, Euglyptoneura and Purshivora. His descriptions are not diagnostic and he also mixed up the figures (fig. 2 concerns Ceanothia and fig. 3 Amorphicola, and not vice versa). Whereas Amorphicola (see Amorphicolinae subfam. nov.) is well characterised by its paramere morphology and by its host associations (Fabaceae), the other three genera are not. Hollis & Martin (1997) redefined Euphalerus Schwarz, 1904 and suggested that the Nearctic species are not congeneric with Euphalerus nidifex Schwarz, 1904, the type species, or with most of the Neotropical species. Percy et al. (2012) transferred these species to Nyctiphalerus. The molecular analyses shed much needed light on the phylogenetic relationships in this group. There are monophyletic clades associated with Rhamnaceae (Ceanothus) and with Rosaceae (Cercocarpus, Purshia). The former is characterised by immatures with a terminal anus and a large circumanal ring which extends onto the dorsum of the caudal plate, the latter has immatures with a ventral anus and a smaller circumanal ring restricted to the venter of the caudal plate. The clade of Ceanothus comprises one group with the genal processes in a lower plane to that of the vertex and lacking a genual metatibial spine (type species of Ceanothia and Euglyptoneura), and another group with genal processes and vertex flattened and in the same plane and bearing a genual metatibial spine (type species of Nyctiphalerus). The Rosaceae clade also splits into two groups: one bearing metatarsal spurs (type species of Purshivora) and one lacking metatarsal spurs (type species of Pexopsylla). Here we suggest that Ceanothia, Nyctiphalerus, Pexopsylla and Purshivora are good genera, and that Euglyptoneura syn. nov. is a junior synonym of Ceanothia (Table 2).

The Oriental genus Cornopsylla is transferred here from Liviidae, Euphyllurinae, Diaphorinini to Psyllidae, Psyllinae. The position of Cornopsylla within Psyllidae is supported by morphological (Luo et al. 2013) and molecular characters (Cho et al. 2019); in both papers, Cornopsylla was treated as a member of Psyllinae.

Psyllinae is a species-rich subfamily (ca 800 spp., Ouvrard 2020) with many species referred to Cacopsylla s. str. and Psylla s. str. that do not fit the restricted concepts of these genera provided above. Awaiting more studies on these species, we leave them in Cacopsylla s. lat. and Psylla s. lat.

Included genera

Anomoneura Schwarz in Uhler, 1896; * Arytaina Foerster, 1848 (syn. Amblyrhina, Ataenia, Psyllopa); * Arytainilla Loginova, 1972 (syn. Hispaniola Ramírez Gómez, 1956 nomen nudum [type species not designated], Lindbergia Heslop-Harrison, 1951 nomen nudum [no included species], Lindbergiella Heslop-Harrison, 1961 nomen nudum [type species not designated], Spartina); * Arytinnis Percy, 2003; Astragalita Loginova, 1976; * Cacopsylla Ossiannilsson, 1970 (syn. Edentatipsylla, Hepatopsylla, Osmopsylla, Thamnopsylla, Psyllia Kirkaldy, 1905 nomen nudum); * Ceanothia Heslop-Harrison, 1961 (syn. Euglyptoneura Heslop-Harrison, 1961, syn. nov.); Cornopsylla Li, 1994; Cyamophila Loginova, 1976; Cyamophiliopsis Li, 2011; Cylindropsylla Li, 2011; Gelonopsylla Li, 1992; * Livilla Curtis, 1835 (syn. Alloeoneura, Floria, Floriella); Mecistoneura Li, 2011; * Nyctiphalerus Bliven, 1955; Palaeolindbergiella Heslop-Harrison, 1961; * Pexopsylla Jensen, 1957; Pseudacanthopsylla Samy, 1972; * Psylla Geoffroy, 1762 (syn. Baeopelma syn. nov., Chamaepsylla syn. nov., Psylla (Labyrinthopsylla) syn. nov., Asphagis Enderlein, 1921); * Purshivora Heslop-Harrison, 1961; * Spanioneura Foerster, 1848 (Asphagidella Enderlein, 1921 syn. nov.).