. Bulletin of the Museum of Comparative Zoology at Harvard College. Zoology. 168 Bulletin Museum of Comparative Zoology, Vol. 141, No. 4. Araneus trifolium Map 7. Distribution of /Araneus trilolium (Hentz). Diagnosis. Araneus trifolium is not close to any other species, although females have been confused with A. (iroenlandicolus and A. iviei on account of the spherical abdo- men, red coloration, and dark leg bands. But the epigynum of A. trifolium is very dis- tinct: a scape (only rarely broken off) flanked on each side by a depression in the base; the margin of the depression and the depress
. Bulletin of the Museum of Comparative Zoology at Harvard College. Zoology. 168 Bulletin Museum of Comparative Zoology, Vol. 141, No. 4. Araneus trifolium Map 7. Distribution of /Araneus trilolium (Hentz). Diagnosis. Araneus trifolium is not close to any other species, although females have been confused with A. (iroenlandicolus and A. iviei on account of the spherical abdo- men, red coloration, and dark leg bands. But the epigynum of A. trifolium is very dis- tinct: a scape (only rarely broken off) flanked on each side by a depression in the base; the margin of the depression and the depression itself are sclerotized and black posteriorly (Fig. 174). The male palpus of A. trifolium has the embolus of an unusual shape (Figs. 178, 180-182); the embolus lamella is a huge flat scale with parallel sides of about the same visible area or larger than the small, narrow conductor (Fig. 179). The lamella, always easily seen, readily separates males from all other North American species. As no illustrations of the male palpus have been readily available, many males of this common species are misidentified in col- lections. Habits. Araneus trifolium is found in meadows and edges of fields making its web between herbaceous plants, often goldenrod {Soliclago sp.), or shrubs, with the hub about m off the ground. The web has about 20 spokes. The web and egg sac have been illustrated by Comstock (1912, 1940). During the recent years of drought the spiders disappeared completely from the fields around our house in Mas- sachusetts but reappeared with the first wet season in summer of 1967, to reach unusual abundance in 1968 and 1969. Kaston (1947) describes the egg sacs after Scheffer as "white, about an inch in diam- eter and delicate enough for the mass of several hundred yellow eggs to show. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may no
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