Psocoptera

Silva-Neto, Alberto Moreira da & Aldrete, Alfonso Neri García, 2020, A checklist of ‘ Psocoptera’ (Psocodea) from Brazil: an update to the list of 2009 of García Aldrete and Mockford, with an identification key to the families, Papéis Avulsos de Zoologia 60, pp. 1-14 : 8-9

Key to families of Psocoptera from Brazil

Adapted from García Aldrete & Mockford (2012) and García Aldrete et al., 2018.

1. Adults with more than 18 flagellomeres; hypopharyngeal filaments separate in their entire length, never fused on midline; labial palpus with minute basal segment and rounded distal segment........................................................................................................................................... Suborder Trogiomorpha … 3

— Adults with less than18 flagellomeres (usually11-13); hypopharyngeal filaments fused along midline at least for part of their length;labial palpus as above,or only one-segmented................................................................................................................................................................................................................. 2

2. Adults with 13 flagellomeres (rarely less); at least some flagellomeres annulated with cuticular sculpture. Labial palpus usually with a minute basal segment and a rounded distal segment.Tarsi usually three-segmented.Forewing,when present,lacking sclerotized pterostigma........... Suborder Troctomorpha … 7

— Adults with11 flagellomeres (rarely less);no flagellomeres annulated with cuticular sculpture but sometimes with reticulate sculpture in cuticle.Labial palpus lacking basal segment,consisting of a single rounded or triangular segment.Tarsi two-or three-segmented.Forewings,when fully developed,with sclerotized pterostigma .................................................................................................................................................................................Suborder Psocomorpha … 11

3. Lacinia slightly simplified.Paraprocts lacking anal spine......................................................................................... Infraorder Prionoglaridetae : Prionoglarididae

— Lacinia normally developed.Paraprocts with anal spine...............................................................................................................................................................4

4. Forewings, when fully developed, with vein Cu2 (CuP) and lA ending separately on wing margin; spur sensillum always present on the second segment of maxillary palpus (Mx2). Ovipositor valvulae:v3 elongate,partially joined together on midline by membrane;v2 small or absent;v1 absent........................... ........................................................................................................................................................................................................... Infraorder Atropetae … 5

— Forewings, when fully developed, with veins Cu2 (CuP) and lA ending together on wing margin (point of junction called ‘nodulus’); spur sensillum of Mx2 present or absent.Ovipositor valvulae:v3 never elongate,but sometimes very broad;v2 usually present,slender;v1 frequently present,slender................... ......................................................................................................................................................................................Infraorder Psyllipsocetae : Psyllipsocidae

5. Body and forewings covered with scales or dense setae.Wings often pointed apically,with visible veins.Mesocoxae of the two sides capable of interlocking by a‘button and cavity’ mechanism......................................................................................................................................................................... Lepidopsocidae

— Body and forewings never covered with scales or dense setae. Wings not pointed apically, with visible veins. Mesocoxae of the two sides not capable of interlocking...............................................................................................................................................................................................................................6

6. Wings,even when very small,with distinct,visible veins.Ovipositor only with valve 3. Opening of the the spermateca with two conspicuous accessory bodies... .................................................................................................................................................................................................................................. Psoquillidae

— Wings reduced, without distinct veins, occasionally absent. Ovipositor mainly with valve 3, but usually also with valve 2. Two denticulated accessory plates (maculas) attached to spermateca................................................................................................................................................................................ Trogiidae

7. Small forms,rarely over 2 mm in length. Males wingless,females usually wingless or brachypterous.Forewings of winged females with not more than two M branches and lacking vein A2.Pearman’s coxal organ absent or represented by a slight bulge in cuticle.....................................Infraorder Nanopsocetae … 8

— Body size variable but usually at least 3 mm in length.Wings present in adults of both sexes, forewings with M three-branched and vein IIA usually present. Pearman’s coxal organ represented by a mirror and a rasp.....................................................................................................Infraorder Amphientometae … 9

8. Body flattened;coxae of opposite sides widely separated by broad sternal plates.Forewings,when present (some females) with two parallel longitudinal veins occupying main body of wing ............................................................................................................................................................................... Liposcelididae

— Body not flattened; coxae of opposite sides only narrowly separated. Forewings, when present (some females), with several branching veins occupying main body of wing........................................................................................................................................................................................................ Pachytroctidae

9. Body and forewings densely covered with scales.In forewing veins A1 and A2 separate for their entire length.................. Amphientomoidea: Amphientomidae

— Body and forewings lacking scales.In forewing veins IA and IIA joined together before reaching wing margin...................superfamily Electrentomoidea … 10

10. Forewing with a long Rs-M crossvein;forewings unpigmented.Outer cusp of lacinial tip with only two denticles................................................... Musapsocidae

— Rs and M in forewing joined at a point;forewings with cloudy pigmentation throughout or with distinct spotting and banding pattern.Outer cusp of lacinial tip with three denticles ............................................................................................................................................................................................. Troctopsocidae

11. Meso-precoxal bridges narrow and corresponding mesotrochantins broad basally.Labrum curved on sides,well molded to contours of mandibles.................... ...........................................................................................................................................................................................................Infraorder Psocetae … 32

— Meso-precoxal bridges and mesotrochantins not as above (i.e., the former wide and the latter narrow basally), or, if otherwise, labrum broad and flat,bearing a longitudinal pair of sclerites................................................................................................................................................................................................. 12

12. Pretarsal claw lacking preapical denticle,forewings and body not densely-setose......................................................................... Infraorder Caeciliusetae … 18

— Pretarsal claw usually with a preapical denticle;if denticle absent (Family Archipsocidae ) forewings and body densely-setose................................................ 13

13. V3 largely fused to v2. Labrum with a pair of longitudinal sutures running through it. Labrum usually flat, not conforming closely to contours of mandibles; mandibles elongate......................................................................................................................................................................Infraorder Epipsocetae … 14

— V3 largely free from v2 and from body wall. Labrum curved on sides, well molded to contours of mandibles, lacking a pair of longitudinal sutures running through it................................................................................................................................................................................Infraorder Homilopsocidea … 22

14. Forewings with one anal vein....................................................................................................................................................................................... Epipsocidae

— Forewings with two anal veins ................................................................................................................................................................................................... 15

15. Forewings with length of A2 equal to or greater than half the length of A1; pterostigma with a spur-vein........................................................ Spurostigmatidae

— Forewings with length of A2 less than half the length of A1;pterostigma without a spur-vein (except Timnewia ).................................................................... 16

16. Lacinial tip with outer cusp slender,bearing not more than three denticles.Pretarsal claw with pulvillus bent near base,expanded at tip...... Dolabellopsocidae

— Lacinial tip with outer cusp broader,bearing more than three denticles.Pretarsal claw with pulvillus straight and pointed distally ......................................... 17

17. Pretarsal claw with a basal spine in addition to the more distal pulvillus.Forewings with or without spur veins, M with three branches.The two labral sutures reaching proximal margin of labrum and curving around to lateral margin......................................................................................................... Cladiopsocidae

— Pretarsal claw with only the spine-like pulvillus. Forewing veins lacking spur veins, M with three to nine branches. The two labral sutures never reaching proximal margin of labrum,except in Willreevesia ................................................................................................................................................. Ptiloneuridae

18. Ventral abdominal vesicles absent.Mesepistemal sulcus absent.Mandibles short to moderate in length..................... Superfamily Asiopsocoidea : Asiopsocidae

— With one to three ventral abdominal vesicles.Mesepisternal sulcus present.Mandibles elongate............................................Superfamily Caeciliusoidea …19

19. Forewings with a crossvein from the pterostigma to Rs stem and another from the M stem to areola postiça......................................................... Stenopsocidae

— Forewings without crossveins as above.......................................................................................................................................................................................20

20. Ciliation of hindwing margin restricted to cell r3 or none.Mx4 longer than Mx2.Spine of free margin of paraproct large .................................... Dasydemellidae

— Ciliation of hindwing margin complete except for basal two-thirds of front margin.Mx4 shorter than or equal to Mx2.Spine of free margin of paraproct small or absent.....................................................................................................................................................................................................................................21

21. Setae of veins in distal half of forewing on both dorsal and ventral surfaces,vein M 2 or 3-branched.Mx4 = Mx 2 in length................................. Amphipsocidae

— Setae of veins in distal half of forewing only on dorsal surface,vein M 3-branched.Mx4 shorter than Mx2 ............................................................... Caeciliusidae

22. In forewings,setae of wing margin in m cells in two series forming crossing pairs.Brachypterous and micropterous individuals with numerous long,backwarddirected setae on vertex and thoracic dorsum......................................................................................................................................................................... 23

— Forewing margin lacking series of crossing hairs.Brachypterous and micropterous individuals with at most only moderate body ciliation............................... 25

23. Venation in forewing vague; Rs in forewing often unbranched. Wings often greatly reduced; in both macropterous and short-winged forms numerous long, backward directed setae on vertex and thoracic dorsum.Usually colonial forms living under dense webbing...................................................... Archipsocidae

— Venation in forewing distinct; Rs in forewing with two branches. Wings usually not reduced. Vertex and thoracic dorsum lacking numerous long, backwarddirected setae.Generally solitary,or a few individuals living together,either in open or under light webbing....................................................................... 24

24. Adults with tarsi two-segmented.External parameres generally much longer than aedeagal arch.Leaf-inhabiting forms ............................... Pseudocaeciliidae

— Adults usually with three tarsal segments.External parameres only slightly longer or shorter than aedeagal arch.Bark-inhabiting forms............... Philotarsidae

25. Macropterous forms....................................................................................................................................................................................................................26

— Micropterous or apterous forms..................................................................................................................................................................................................29

26. Forewings with vein CuA1present and usually free from M.Wings either unciliated or lightly ciliated.Ovipositor reduced to one(v3),rarely two valvulae on each side ......................................................................................................................................................................................................................... Lachesillidae

— Forewings lacking vein CuA1.Wings lightly to moderately ciliated.Ovipositor usually with three valvulae,rarely reduced to one on each side......................... 27

27. Vein R 1 in pterostigma parallel to wing margin most of its length................................................................................................................... Ectopsocidae (part)

— Vein R 1 in pterostigma curved....................................................................................................................................................................................................28

28. Both sexes macropterous.Phallosome elongate,with heavily sclerotized endophallic structure distally in form of a three-pronged fork........ Peripsocidae (part)

— Either males or females macropterous,not both.Endophallus not as above........................................................................................................ Elipsocidae (part)

29. Body with some spinous bristles facing upwards................................................................................................................................................. Elipsocidae (part)

— Body without spinous bristles..................................................................................................................................................................................................... 30

30. Antenna much shorter than the body.Subgenital plate with a distal median lobe,simple,thin (egg guide)...................................................... Elipsocidae (part)

— Antenna about as long as the body.Subgenital plate with a relatively wide median distal protuberance or with two distal protuberances.............................. 31

31. Epistomal suture present dorsally,separating frons from postc1ypeus.Subgenital plate usually with two distal processes............................. Ectopsocidae (part)

— Epistomal suture absent dorsally,postclypeus and frons continuous.Subgenital plate with a single,relatively broad median distal process.... Peripsocidae (part)

32. Vein M in forewing two-branched,the M stem joined to vein CuA1 by a long crossvein;hind tibia lacking longitudinal row of ctenidiobothria...... Hemipsocidae

— Vein M in forewing three-branched, the M stem usually fused for a short distance to vein CuA1; rarely the two joined by a short crossvein. Hind tibia with a longitudinal row of ctenidiobothria........................................................................................................................................................................................33

33. Tarsi three-segmented;forewings heavily blotched with brown,the margins with altemating brown and colorless banding................................... Myopsocidae

— Tarsi two-segmented;forewing markings variable,but margins not with altemating brown and colorless banding ........................................................ Psocidae