56 MORPHOLOGY AND TAXONOMY OF ADULT MALES 



extending anteriorly from base of aedeagus to the apex of basal membranous area ; apex of 

 sheath without membranous extension. The area from base of sheath to tip of aedeagus with 

 17—22 (average 19) small setae ; a cluster of small sensilla occurring ventrally near apex of 

 sheath. Aedeagus broad at its base and tapering towards tip ; long (129-148, average 141 \i), 

 penial sheath longer and basisternum as long or longer, the ratios being 1 : 1-8-2-0 (average 

 1-9) and 1 : 0-99-1-14 (average 1-04) respectively. 



Material examined : 10 specimens, bred from material collected by myself on 

 Crataegus sp. (hawthorn) on Putney Heath, London ; males emerged in the 

 laboratory between the 19th and 22nd June, 1962. Four specimens, collected by 

 J. Rehacek on Crataegus oxyacantha L. in Novy Bydzov, Czechoslovakia on 18.vi.52 

 (remounted from Swann's mountant) agreed well with the above description, but 

 differed in the following respects : (i) 2 specimens were longer, measuring 1490 \i 

 each, (ii) the darker median sclerotization on the prescutum was less well developed 

 and not ridge-like in appearance and (iii) the reticulation on the prescutum was 

 more distinct. 



PHYLLOSTROMA 



Phyllostroma myrtilli (Kaltenbach) 



(Text-figs. 12 and 13) 



A small, slender species with comparatively long antennae and short legs ; with many setae 

 on the appendages, but few on the body itself. When mounted, total body length 1 460-1 620 

 (average 1553) jx ; width at mesothorax 370-410 (average 387) [x. Wing expanse 2870-3010 

 (average 2940) \l. 



Head subconical in dorsal view ; in lateral view obliquely dorsoventrally elongated, with 

 anterodorsal bulge not pronounced ; length to pronotal ridge 209-247 (average 226) ;x, width 

 across genae 255-270 (average 262) [x. Median crest sclerotized and distinctly polygonally 

 reticulated ; with 6—10 (average 7-4) hair-like dorsal head setae, arranged in a group of 3-5 near 

 anterior margin of head and a group of 2-5 more posteriorly. Midcranial ridge dorsally absent ; 

 ventrally narrow but well defined, surrounding area weakly sclerotized and distinctly poly- 

 gonally reticulated. Genae large, sclerotized, not reticulated, without setae. Eyes four 

 pairs ; dorsal and ventral pairs large, subequal ; lateral pairs smaller, subequal ; corneae of 

 dorsal eyes 23-27 (average 24) u. in diameter and 3-4-4-5 (average 4-1) times as much apart ; 

 those of the ventral eyes 25-30 (average 28) jx in diameter and 1 -3-1 -7 (average 1 -5) times as 

 much apart. Ocellus small. Ocular sclerite well sclerotized and polygonally reticulated 

 throughout. Preocular ridge short, not extending far below articular process. Postocular ridge 

 weak and tapering dorsally, but well developed lateroventrally and posteromedially ; below 

 ocellus the ridge splits up, with anterior branch partly surrounding ocellus. Interocular ridge 

 absent. Dorsal ocular setae absent ; ventral head setae : 8-14 (average 10) h.s., situated around 

 posterior part of the midcranial ridge. Preoral ridge present. Tendon-like apodeme short. 

 Cranial apophysis of medium length ; apex bifurcate with central lobe, not reaching level of 

 anterior margin of ventral eyes. Mouth opening irregular. Anterior tentorial pits present, 

 situated anterolateral to mouth opening. 



Antennae 10-segmented, filiform ; 910-1053 (average 986) ;x long, i.e. longer than half bod}' 

 length (ratio 1 : 1-43-1-65, average 1-57), longer than posterior leg (ratio 1 : 1-23-1-33, average 

 1-27) and longer than penial sheath (ratio 1 : 3 15-3 -47, average 3-36). Scape long (length 

 65-68, average 66 jx) and 42-48 (average 45) (x wide, with 1-3 (average 2) h.s. Pedicel not 

 reticulated, but with one or two wavy lines ; 61-68 (average 65) fx long and 42-46 (average 44) 

 (x wide ; with 5-10 (average 7-4) f.s., 3-5 (average 3-7) h.s., and a sensillum placodeum. 

 Segment III club-shaped, 2-5-3-1 (average 2-8) times longer than wide (76-84, average 79 [x long 



