REVISION OF LEUCOSPIDAE 63 



Leucospis affinis Say 



(Text-figs 61-63) 



Leucospis affinis Say, 1824 : 63-64, $ <£. 



As several subspecies are recognized the synonymy and some other data are 

 given below under the relevant names. 



L. affinis is the commonest and most widely spread North American species 

 and so it is not surprising that it shows fairly wide variation. The length of body 

 in the specimens examined is in the female 3-9-11-5 mm, in the male 3-6-9-8 mm, 

 the dwarfs coming, possibly, from smaller hosts at less favourable conditions. 

 The body in general is fairly slender but some southern specimens (e.g. from 

 Concepcion Bay, Lower California, Mexico) are rather robust, the gaster in the 

 female being only i-8 times as long as broad, compared with the average 2-5 times 

 as long as broad (a similar case is known to me in the southern specimens of L. 

 dorsigera Fabricius in the Mediterranean subregion). At the same time the apex 

 of the gaster may be narrowly or broadly rounded. The puncturation also shows 

 the greatest deviations in the south: in many specimens from Lower California 

 the punctures on the face are conspicuously less crowded than normally and in 

 some dark Mexican forms (attributed below to ssp. dubiosa Cresson) the puncturation 

 of hind femur and coxa is unusually dense. 



The colour varies greatly but generally keeps to a certain pattern, apart from 

 the red which normally replaces black on the base of gaster, on hind coxae, on 

 antennae and rarely on some other parts of the body (although rufinism seems 

 to be rather rare in L. affinis). In the average form the following parts are pale 

 yellow: scapus beneath, pronotum dorsally along posterior and lateral margins 

 and on a cross-band anteriorly, mesoscutum laterally, scutellum posteriorly, 

 metapleurum dorso-posteriorly, all knees, tibiae except fore and mid ones externally 

 and hind tibiae except along the ventral edge, hind femur beneath basally and 

 along dorsal edge towards apex; in the female the first and fifth tergite with a 

 cross-band posteriorly, the fourth tergite and epipygium with vertical streaks; 

 in the male the first, fourth and fifth tergites posteriorly with a cross-band, the sixth 

 tergite with median elongate spot. In the female the yellow may spread to cover 

 most of the pronotum except a quadrangular cross-band on the disc, to form two 

 submedian spots on mesoscutum and one on upper mesepisternum, and yellow is 

 most of the scapus, metapleurum, the femora and tibiae, then all gastral segments 

 except narrow margins; in the male all the gastral segments except the second 

 tergite and epipleurum of the first may bear broad bands, the sixth tergite may 

 have a large deltoid yellow area. The lessening extent of the pale markings is 

 apparent first on the gaster, where the cross-bands may be interrupted medially 

 whilst the mesoscutum still retains the submedian spots. In the darkest form 

 the lateral fines on pronotum become narrow, the anterior band is reduced to a 

 short line or a double spot (in affinis affinis, e.g. in two males from Nevada, both 

 under 4 mm, in which also the gastral bands are much reduced and on the fourth 

 tergite to mere transverse spots on either side), or may disappear completely (in 



