242 



Denning: Trichoptera 



9. Anterior tibiae with preapical spur 



PSYCHOMYIIDAE (in part) 



— Anterior tibiae without preapical spur 10 



10. Mesoscutum without warts (fig. 10:4c}, hind wings 

 with radius about normal and the stem distinct from 

 subcosta HYDROPSYCHIDAE 



— Mesoscutum with a pair of warts (fig. 10:4c), hind 

 wings with the radius reduced and the stem absent or 

 fused with the subcosta PSYCHOMYIIDAE 



11. Middle pair of tibiae without preapical spurs 12 



— Middle pair of tibiae with preapical spurs 16 



12. Antennae long, slender, about twice the length of the 

 fore wings; mesonotum with a long, irregular line of 

 setate spots LEPTOCERIDAE 



— Antennae stouter, equal to or slightly longer than 

 fore wings; mesonotum either with scutal warts small 

 (fig. 10:4/1), or with none (fig. 10:4/) 13 



13. Anterior tibiae with 1 spur; hamuli present on hind 

 wings HELICOPSYCHIDAE 



— Anterior tibiae with 2 spurs; hamuli absent 14 



14. Middle and hind tarsi with a group of 4 black spines 

 at apex of each segment (fig 10:4;') BERAEIDAE 



— Middle and hind tarsi with apical spines separated, 

 not grouped together as above 15 



15. Scutal warts of mesoscutum near meson (fig. 10:4a'); 

 front wings with a long cross vein between R, and 

 R, SERICOSTOMATIDAE 



— Scutal warts some distance from meson (fig. 10:4e); 

 front wings without cross vein between R, and R a 



BRACHYCENTRBDAE 



16. Middle femora with a row of 6-10 black spines 



MOLANNIDAE 



— Middle femora with 0-2 black spines 17 



17. Mesonotum with scutal warts arranged as a lineal 

 area of small setate spots extending the full length 

 of the scutum (fig. 10:4£) CALAMOCERATIDAE 



— Mesonotum with scutal warts oval or lanceolate and 

 short (fig. 10:4s) 18 



18. Mesoscutellum with single large wart extending its 

 entire length (fig. 10:4i) 19 



— Mesoscutellum with 2 warts (fig. 10:4e) 20 



19. Maxillary palpi of males 5-segmented; tibial spurs 

 not hairy ODONTOCERIDAE 



— Maxillary palpi of males 3-segmented; tibial spurs 

 hairy (fig. 10:4i) GOERIDAE 



20. Middle tibiae with spines; preapical spurs of tibiae 

 bare BRACHYCENTRIDAE 



— Middle tibiae without spines; preapical spurs of tibiae 

 hairy LEPIDOSTOMATIDAE 



Larvae 2 



1. Larvae campodeiform. Terminal abdominal prolegs 

 not fused to form an apparent 10th segment; tubercles 

 absent on 1st abdominal segment; prosternal horn 

 absent 2 



— Larvae eruciform or s uberuciform. Basal segments of 

 terminal abdominal prolegs fused to form an apparent 

 10th segment; tubercles present on 1st abdominal 

 segment; prosternal horn present (fig. 10:6) 6 



2. Abdomen swollen, much wider than thorax, without 

 gills; small larvae living in silken cases (fig. 10:3a, b) 



HYDROPTILIDAE 



— Abdomen only slightly wider than thorax, cases when 

 present not entirely made of silk but utilizing bits of 

 debris, most larvae free living 3 



3. Sclerotized shield present on dorsum of 9th abdominal 

 segment (fig. 10:56) RHYACOPHILIDAE 



— Sclerotized shield absent, dorsum of 9th abdominal 

 segment entirely membranous 4 



4. Tracheal gills branched, abundant, on venter of ab- 

 domen HYDROPSYCHIDAE 



— Tracheal gills absent on abdomen 5 



^Adapted from Ross (1944) and Betten (1934). 



Fig. 10:5. Larval structures, a, Polycentropus, labrum; b, 

 Rhyacophila, apex of abdomen; c, Chi'marro, labrum; d, Psilotreia, 

 thorax; e, He/i'copsyche, anal hooks; f, Brachycentrus, anal 

 hooks; g, Lepfocerus, larval antenna; h, Sen'cosfoma, anal hooks; 

 i, Alhripsodes alagmus, head and pro- and mesonota; /', Li'mne- 

 philus, larval antenna; k, Lepidostoma, larval antenna; /, Rhy' 

 acoph/'/o, adult front tibia; m, Protoptila, anal hooks (Ross, 1944). 



5. Labrum expanded distally, entirely membranous (fig 

 10:5c) PHILOPOTAMIDAE 



— Labrum shorter, entirely sclerotized (fig. 10:5a) .... 



PSYCHOMYIIDAE 



6. Claws of hind legs very small, those of front and 

 middle legs large MOLANNIDAE 



— Claws of hind legs long, subequal to those of middle 

 legs 7 



7. Antennae long, arising at base of mandibles (fig. \0:5g) 



LEPTOCERIDAE 



— Antennae short, often very inconspicuous; arising from 

 various locations (fig. 10:5j,k) 8 



8. Mesonotum submembranous except for a pair of par- 

 enthesislike sclerotized bars (fig. 10:5t) (Athripsodes) 



LEPTOCERIDAE 



— Mesonotum without such sclerotized bars or with plates 

 of different shape than above 9 



9. Meso- and metanotum entirely membranous, each with 

 lateral tuft of long setae; lateral gills covered with 

 hair PHRYGANEIDAE 



— Meso- and usually metanotum with at least some con- 

 spicuous sclerotized plates 10 



10. Labrum with distinct transverse row of 20 or more 

 stout setae across middle of dorsal surface 



CALAMOCERATIDAE 



— Labrum lacking such a row of setae, 6-8 long setae 

 at most 11 



11. Teeth on anal hooks comblike (fig. 10:5e); trachael 

 gills very small; case shaped like a snail shell (fig. 

 10:3<?) HELICOPSYCHIDAE 



