ADDITIONAL NOTES ON THE ORB-WEAVER 
GENERA ARANEUS , HYPSOSINGA , AND SINGA 
NORTH OF MEXICO (ARANEAE, ARANEIDAE)* 
By Herbert W. Levi 
Museum of Comparative Zoology, Harvard University 
Introduction 
After my first Araneus study was published in 1971 I was 
informed by W. J. Gertsch and V. Roth that the males of A. 
illaudatus are found with females of my newly described A. pima. 
However, owing to the great size difference and abdominal pattern 
difference, I remained stubbornly unconvinced that they could belong 
to the same species until spiderlings from an egg-sac raised by P. 
Witt grew up into female A . pima and male A. illaudatus. This 
persuaded me but raised some new questions, as the hand-reared 
males are larger, the females smaller, than in wild populations (see 
below) . 
While establishing this synonymy (in Levi, 1971), I take this 
opportunity to report on an additional new species of Araneus from 
the Southwest (Levi, 1973), as well as to report range extensions 
from the American Museum Singa and additional Araneus collec- 
tions and from the R. V. Chamberlin (University of Utah) col- 
lection, now again available. I will publish later on a number of 
tiny new species of Araneus, most collected as provisions by wasps. 
I would like to thank W. J. Gertsch, V. Roth, N. Platnick, of 
the American Museum of Natural History, S. Frommer, F. Enders 
and P. Witt for specimens, E. Mayr and Lorna R. Levi for reading 
the manuscript. National Science Foundation Grant BMS 75-05719 
supported the researches and publication. 
Size Variations 
For unknown reasons, size differences between sexes and among 
individuals of the same sex within populations are much greater in 
orb-weavers in the superfamily Araneoidea than in other spiders, 
although adult size variations are common in arachnids. These dif- 
ferences, due to variation in the number of instars before maturity, 
have been commented on by others (e.g. Gerhardt, 1929, 1930; 
Probst, 1972 in Isometrus scorpions). 
* Manuscript received by the editor September 10, 1975 
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