Strauzia bushi Lisowski, New Species

Diagnosis

Males of this species can be identified by a distinctive wing pattern, which is chocolate brown in color. Wing bands coalesce and accessory costal and anterior apical crossbands are united so that cell R1 has only one hyaline area and cells R, R3 and R5 lack hyaline areas. Females are unknown.

Description

Male:

Wing pattern is in Figure 9. Frequency and mean score of nominal variables with intraspecific variation are in Table II. Supracervical setulae yellow; dorsomedial vitta at anterior edge of thorax black; dorsolateral vitta anterior from transverse suture absent; dorsolateral vitta posterior from transverse suture absent; supra-alar vitta absent; two scutellar spots black; two postnotal spots brown; mesepimeral spot absent; hypopleural spot absent; fifth tarsomere of all legs yellow; propleural setulae usually black (2), rarely brown (1); setae on dorsal surface vein R4+5 distal of r-m crossvein absent; microtrichia on dorsal surface of cell R present; no hyaline areas in discal cell; hyaline area in cell R absent; hyaline area in basal medial cell absent; stigma yellow; humeral crossvein dark brown; vein CuA2 dark brown; predominant color of bands in radial cells dark brown; predominant color of bands in discal and apical medial cells dark brown; edge of wing band in radial cells dark brown; band along costa between veins R2+3 and M continuous; accessory costal and anterior apical crossbands in cell R1 united; accessory costal and subapical crossbands in cell R3 broadly united; accessory costal/discal and subapical crossbands in cell R5 broadly united; discal and subapical crossbands in cell CuA1 not united; subapical crossband at vein R4+5 continuous; major abdominal bristles black; abdominal tergites with lateral margins yellow; abdominal tergite 2 yellow; side of epandrium brown.

The mean, standard error of the mean, number of individuals, and range of the meristic variables are in Appendix I, of the continuous variables are in Appendix II, and of the derived variables are In Appendix III.

Discussion

None of the descriptions of the seven varieties of Trypeta (Straussia) longipennis that were presented by Loew (1873) characterize S. bushi. Only his variety longitudinalis has a dark brown, coalesced pattern. He notes that "the interval between the second and fourth longitudinal veins [vein R2+3 and vein M] is completely filled by this stripe, with the only exception of a small hyaline spot at the end of the fourth longitudinal vein; moreover, the stripe encroaches a little beyond the second and fourth veins in the shape of little wavy expansions." The pattern of S. bushi completely fills the interval between vein R2+3 and vein M and extends considerably into cell R1 and completely joins the costal margin between vein R1 and vein R2+3.

I have not seen females of this species and know nothing about its larval host plants. In addition to the nine specimens that I examined from McLean Co., I have collected two specimens from 1 mile South of Savoy, Champaign Co., on 28-VI-1978. These two specimens were analyzed in my study of allozymes of Strauzia, but not included in my thesis (Lisowski, 1979) because of the small sample size. Both collections were made while I was sweeping H. grosseserratus for S. arculata. The wing pattern of S. bushi resembles a very dark brown, coalesced pattern of S. arculata, but the results of the allozyme study (unpublished data) suggest that these species are not closely related. I found fixed differences between these species at four of the sixteen enzymes that I analyzed. This is a high degree of genetic differentiation in Strauzia.

Tables and Figures