Phylinae, Douglas & Scott, 1865

Yasunaga, Tomohide, 2022, The plant bug subfamily Phylinae in Japan, with key to genera and descriptions of eight new species (Hemiptera: Heteroptera: Miridae), Zootaxa 5094 (1), pp. 1-52 : 3-5

Key to Japanese genera of Phylinae

1. Anterior margin of pronotum constricted, with distinct collar (cf. Fig. 17A); epigeic phylines usually with stridulatory device (as in couplet 3 below)...................................................................... 2 [ Hallodapini ]

– Anterior margin of pronotum without noticeable collar, only with faint, narrow fold in some taxa; stridulatory device not present.............................................................................................. 5

2. Total body length> 5.3 mm; head with a distinct, sharp, horn-like process on frons and a longitudinal mesal sulcation on vertex (Fig. 17A); vertex with a distinct, longitudinal, mesal sulcation; always macropterous..................... Acrorrhinium

– Total body length <5 mm; frons smooth, without any noticeable process or mesal sulcation; vertex not sulcate; female often brachypterous (coleopteroid or staphylinoid)................................................................ 3

3. Total body length> 4 mm; hemelytral edge and dorsal metafemur smooth, without stridulatory device; female micropterous, with widely exposed abdomen; usually found on herbs in northern Japan................................ Systellonotus

– Body small, up to 3.6 mm in total length; hemelytral edge and dorsal metafemur with stridulatory device (plectra or minute bumps) (Fig. 17D–F); in short-winged female, reduced hemelytron covering at least abdominal terga IV–V; mostly epigeic and thermophilic......................................................................................... 4

4. Similar to Pilophorus species (but body lacking silvery setae); always macropterous; corium uniformly castaneous to dark brown; pretarsus with rather fleshy, apically convergent parempodia (Fig. 17B); habitat currently unknown...... Cleotomiris

– Body elongate; female often brachypterous and membrane obliterated (coleopteroid or staphylinoid); corium orange or dark brown with one or paired white (or pale) spots (but in some brachypterous females with uniformly brown or dark brown hemelytra); parempodia hair-like (Fig. 17C); epigeic................................................ Hallodapus

5. Body large, more than 4.8 mm (mostly> 5 mm) in total length................................................. 6

– Body smaller, ≤ 4.6 mm ................................................................................ 7

6. Distinct sexual dimorphism present in coloration (body generally dark brown in male/ reddish or orange brown in female); male antennal segment II sulcate apically, with blush-like setae (Fig. 17G); labium short, not exceeding apex of procoxa; pulvilli swollen ( Fig. 17H )............................................................................ Harpocera

– Body generally dark brown in both sexes; dorsum less shining, with densely distributed, dark simple setae and silvery reclining setae; antennal segment II smooth, cylindrical; labium exceeding apex of mesocoxa; parempodia hair-like........................................................................................ Psallus (part, subgen. Apocremnus )

7. Parempodia more or less thickened, fleshy or ribbon-like ( Fig. 17O ), or pulvilli noticeably developed and thicker than claw ( Fig. 17I )............................................................................................ 8

– Parempodia hair-like, setiform or slender; pulvilli narrower than claw (e.g., Figs. 17N , 21F )......................... 16

8. Dorsum without transparent portion nor silvery setae.............................................. Brachyarthrum

– Hemelytron opaque, without transparent portion; silvery scalelike or flattened setae on dorsum uniformly distributed or partly clustered, forming patches or bands............................................................ 9 [ Pilophorini ] * Most part of hemelytron transparent (sometimes semitransparent, with scattered dark small spots); silvery setae on dorsum (if any) usually sparsely distributed........................................................................ 14

9. Body elongate, more or less antlike; silvery scale-like setae on hemelytron linearly or roundly clustered even in non-antlike species...................................................................................... Pilophorus

– Body ovoid, elongate-oval or rounded, sometimes disk-like or tortoise-shaped; silvery scale-like setae on hemelytron (if any) not clustered, sparsely, or uniformly distributed, or forming broad band at middle................................. 10

10. Antennal segment II remarkably enlarged, terete or boxlike............................................ Druthmalus

– Antennal segment II not strongly enlarged or almost linear, or slightly incrassate towards apex (apical part less than twice as thick as base)....................................................................................... 11

11. Pronotum darkened, shiny, lacking silvery setae............................................................ 12

– Pronotum either less shining (sometimes matte) or more or less (sometimes densely) covered with silvery scale-like setae. 13

12. Hemelytron matte, brick-red or reddish brown.......................................... Pilophorus (part, P. tagoi )

– Hemelytron shiny dark brown to fuscous............................................................ Pherolepis

13. Body short-ovoid, tortoise-shaped; thoracic pleurites with anterior and posterior glands; tibia with clear dark annulation, or rings; specialists of Santatalean hemiparasitic mistletoes............................................. Hypseloecus

– Body ovoid or elongate oval; thoracic pleurites without such glandular structure; tibia without dark annulation; inhabiting graminoid grasses or sedges.................................................................... Sthenaridea

14. Head roundly flattened in front; pulvilli enlarged, much thicker than claw................................... Decomia

– Head more or less pointed in front; pulvilli small........................................................... 15

15. Antennal segment II pale, with 3 clear dark annulations; pronotum and scutellum uniformly vivid pale green; tibia with distinct dark spots at bases of spines......................................................................... Opuna

– Antennal segment II uniformly brownish, or either its base or apex darkened; pronotum and scutellum usually irregularly darkened or spotted, but if pronotum and scutellum wholly pale, then tibia without dark spots at bases of spines... Moissonia

16. Body with both dark simple setae and slivery setae on dorsum and lateral side; antennal segment II remarkably claviform, with its apical width about 3 times as thick as base..................................................... Atractotomus

– Antennal segment II almost linear (even if silvery setae present on dorsum or lateral side); if antennal segment II thickened towards apex, then dorsum and lateral side of body lacking silvery setae......................................... 17

17. Apical 1/3–1/2 of anterior margin of metafemur with a row of recognizable minute spicules ( Fig. 17J , white arrows)................................................................................................ Campylomma

– Anterior margin of metafemur without visible spicules [if present, spicules difficult to be observed by stereoscopic microscope as in Fig. 17K–L ].................................................................................... 18

18 Body almost uniformly orange yellow, without noticeable spot or macula............................... Sasajiophylus

– Body widely darkened, or somewhere with maculae or spots.................................................. 19

19. Body tiny, less than 1.8 mm in total length (smallest mirids in Japan); whole antenna and pro- and mesofemora uniformly creamy yellow (often pale brown in dry-preserved specimen); thermophilic species occurring on Ryukyus...... Decomioides

– Total body length ≥ 2.0 mm; any of antenna and pro- and mesofemora (at least partly) darkened or spotted............. 20

20. Dorsum uniformly creamy white, or whitish brown; base and apex of cuneus with clear scarlet or sanguineous spots.............................................................................................. Rubrocuneocoris

– Dorsal coloration not as above.......................................................................... 21

21. Dorsum almost uniformly shiny fuscous, polished [if metafemur pale with clear dark spots or stripe, proceed to couplet 36: Plagiognathus ]...................................................................................... 22

– Dorsum pale or different coloration; in darkened species, dorsum less shining or with dense vestiture.................. 27

22. Vestiture on pronotum sparse, indistinct............................................................. Salicarus

– Pronotum with uniformly distributed vestiture............................................................. 23

23. Apical part of metafemur with small dark spots.................................................... Parapsallus

– Metafemur almost uniform in coloration, without spotted pattern, or darkened basally with yellowish, brownish, or reddish apical part (cf. Fig. 9H )............................................................................... 24

24. Dorsum with distinct silvery reclining setae (that are easily rubbed away while collecting or mounting) ( Figs. 9A–B, D vs. 9E–G; 24M–O)............................................................................... Orthonotus

– Dorsum with simple (usually dark) setae only.............................................................. 25

25. Body elongate, slender, more than 4 mm in total length; all femora wholly creamy yellow [if body elongate and darkened, then femora more or less darkened: Plesiodema , part]........................................................ Phylus

– Body ovoid to elongate oval, less than 3.5 mm in total length; at least basal part of each femur darkened [if all femora creamy yellow, then body smaller (<3.5 mm) and apical part of metafemur usually obscured or reddish]..................... 26

26. Metathoracic scent efferent system with a developed, projected peritreme; pro- and mesofemora uniformly creamy yellow............................................................................................ Pseudophylus

– Metathoracic scent efferent system with a small, flattened peritreme; pro- and mesofemora darkened basally........ Sejanus

27. Dorsum with scattered dark or reddish spots............................................................... 28

– Dorsum without such spots............................................................................ 29

28. Basic coloration of dorsum creamy white or whitish brown.......................................... Compsydolon

– Basic coloration of dorsum uniformly castaneous, reddish to dark brown; small spots on hemelytron dark brown, uniformly distributed............................................................................... Atractotomoidea * Dorsum pale reddish brown or orangish brown; hemelytral small spots reddish brown or orangish brown, sparsely distributed....................................................................... Psallus (part, subgen. Callopsallus)

29. Dorsum and lateral side of body with both simple setae and silvery (or sometimes golden) setae...................... 30

– Dorsum and lateral side of body with simple setae only...................................................... 36

30. Labium very long, far exceeding beyond apex of metacoxa, reaching VI–IX abdominal segment........ Pityopsallus (part)

– Labium shorter, not exceeding apex of metacoxa........................................................... 31

31. All femora almost uniformly brick red, reddish brown or dark brown, without noticeable spotted pattern...... Kasumiphylus

– At least metafemur widely darkened or yellow, or any of femora with spotted pattern.............................. 32

32. Silvery setae transversely sculptured or grooved ( Fig. 17M ); pronotum slightly wider than head across eyes; tropical or subtropical climatic zone inhabitants currently known only from Ryukyus (Okinawa Pref.)....... Lasiolabops [ Pilophorini ]

– Silvery setae not distinctly sculptured or grooved ( Figs. 18C ; 28F, K ); pronotum obviously wider than head across eyes; north of Kyushu.......................................................................................... 33

33. Vestiture on dorsum roughly or randomly upright or curled-up ( Fig. 18A–B, I–J ); labium not exceeding median part of mesocoxa ( Fig. 18H, K ); pronotum and scutellum shagreened, relatively matte ( Fig. 2A, C ).......................... Eremophylus

– Dorsal vestiture uniformly distributed, not curled-up; labium reaching or exceeding apex of mesocoxa; pronotum and scutellum more or less shining, not shagreened..................................................................... 34

34. Dorsum uniformly darkened, not tinged with red; basal margin of cuneus obviously pale or semitransparent as in Fig. 11 ; restricted to boreal conifers............................................................... Pityopsallus (part)

– Dorsal coloration variable; if dorsum darkened, then hemelytron more or less reddish, or cuneus uniformly dark or its base only narrowly pale [if base of cuneus widely pale (cf. Fig. 5A, D ), then body length less than 3.2 mm]; associated with herbs or broadleaf trees.................................................................................... 35

35. Dorsum generally dark brown (with more or less darkened antennal segment II and always with pale anterior margin of cuneus), or uniformly pale brown or yellowish, without reddish tinge; right paramere enlarged and squared, longer than left paramere; inhabiting herbs (mostly Asteraceae , rarely Laminaceae)............................................... Europiella

– Basic coloration variable (in dark species, hemelytron including cuneus uniformly darkened but antennal segment II uniformly pale brown or yellow; in pale species, dorsum at least partly reddish or darkened); right paramere usually elongate-ovoid or spindle-shaped (cf. Fig. 30E, H, L ), shorter than left paramere; arboreal (mostly deciduous broadleaf trees)......... Psallus

36. Femora and tibiae almost entirely pale; extreme base of metatibia (knee) with a dark small spot or narrow annulation..................................................................................................... Tytthus

– Femora and tibiae somewhere with darkened part, stripe and/or spot; extreme base of metatibia without such knee-spot... 37

37. Body darkened, ovoid, with inner margin of eye and anterior margin of cuneus always yellowish brown; metafemur usually widely darkened........................................................................... Monosynamma

– Body elongate oval; basic coloration variable (in dark species head and dorsum uniformly darkened); metafemur with spotted and/or striped pattern....................................................................... Plagiognathus

Figures

FIGURE 2. Dorsal (A, C, F, H) and ventral (B, D, E, G, I) habitus images of Eremophylus spp. A–B. E. hirtus, female. C–D. E. nakagawai sp. n., male. E. Same, partly paler variant. F–G. Same, female. H–I. Same, paler variant.

FIGURE 5. Habitus images of living individuals of Japanese Europiella spp. A. E. artemisiae, male. B. E. decolor, male (pale variant). C. Same, female (pale variant). D. Same, female. E. E. lividella, female. F–G. E. isodonicola n. sp., male. H. Same, female. I. Same, 5th instar nymph. J. E. miyamotoi, female. K. Same, 5th instar nymph. L. E. nihonica n. sp., female.

FIGURE 9. Habitus images of Orthonotus spp. A−C, H. O. nakagawai n. sp. D–E. O. takaii n. sp. F–G. O. bicoloripes (from Primorsky, FE Russia). A, D, E, F, H. Male. B, G. Female. C. Fifth instar nymph. Images courtesy of Y. Nakagawa, Akita (A–C) and M. Takai, Kochi (D).

FIGURE 11. Dorsal (A, E, C, F) and ventral (B, D) habitus images of Pityopsallus spp. A–B. P. maeharai n. sp., male. C–D. Same, female. E. P. sakuraii n. sp., holotype male. F. P. vittatus, female (from Yakutia, Russia).

FIGURE 17.Scanning electronmicrographs forvarious phyline taxa.A. Acrorrhinium inexpectatum Josifov,head and pronotum. B. Cleotomiris miyamotoiYasunaga, pretarsal structure of metaleg.C. Hallodapus centrimaculatus (Poppius), same. D−F. Stridulatory device of H. brunneus (Poppius, 1915) (D: edge of forewing, or exocorium and F: dorsal metafemur). G. Harpocera orientalis Kerzhner, male antennomere II. H. Same, pretarsal structure of metaleg. I. Decomia cephalotes Poppius, same. J. Campylomma lividicorne Reuter, metafemur. K. Atractotomus morio J. Sahlberg, apical metafemur. L. Kasumiphylus kyushuensis (Linnavuori), same. M. Lasiolabops cirratus Yasunaga & Duwal, embolium and thoracic pleura, left lateral view. N. Same, pretarsal structure of metaleg. O. Pilophorus typicus (Distant), same. Abbreviations—cw: claw, pp: parempodium, pv: pulvillus.

FIGURE 18. Scanning electron micrographs for Eremophylus hirtus (A−G) and P. nakagawai n. sp. (H−O). A, D, H. Left lateral habitus. B, I, J. Dorsal habitus. K. Ventral habitus. C. Corium. E, M. Thoracic pleura, left lateral view. F, N, O. Metatarsus. G, L. Apex of labium.

FIGURE 21. Scanning electron micrographs for Europiella isodonicola n. sp. (A−F), E. miyamotoi (G−L), E. lividella (M−N) and E. senjoensis (O). A, G, M. Left lateral habitus. B, H. Head, dorsal view. C, I. Thoracic pleura, left lateral view. D, J. Metafemur, ventral view. E−F, K−L. Metatarsus. N. Male genital segment. O. Corium.

FIGURE 28. Scanning electron micrographs for Pityopsallus luridus from Yakutia, Russia (A−C), P. yasunagai (Vinokurov) (D–F, O), P. ermolenkoi (Kerzhner) (G–I, M), P. sakuraii n. sp. (J), P. vittatus (K, N) and P. nipponicus (Vinokurov) (L). A. Anterior body, dorsolateral view. B. Vestiture pattern on scutellum and anterior hemelytron. C–D, G–L. Male genital segment (pygophore), left lateral view. E. Same, caudal view. F. Apex of vesica. M–O. Pretarsal structure of metatarsus.

FIGURE 30. Scanning electron micrographs for Psallus (Hylopsallus) castaneae (A−F), P. (H.) ramae n. sp. (G−M) and P. (H.) tonnaichanus (N−O). A, G, N. Left lateral habitus. B. Vestiture pattern on anterior thorax. C, H. Thoracic pleura, left lateral view. D, E, I, J, K, O. Male genital segment, left lateral view (J–K, O: clustered stiff setae). F, L, M. Metatarsus.