ORB PLUS CONE-WEBS IN ULOBORIDAE (ARANEAE), 
WITH A DESCRIPTION OF A NEW GENUS 
AND FOUR NEW SPECIES 
By Y. D. Lubin, 1 , B. D. Opell, 2 , W. G. Eberhard, 3 
and H. W. Levi 4 
Introduction 
Spiders of the genus Uloborus (Uloboridae) characteristically 
spin horizontal orb-webs with a sticky spiral of cribellar silk. We 
describe here the webs of U. conus, U. albolineatus, U. bispiralis, U. 
#2072, U. trilineatus, and Conifaber parvus which are modifications 
of this basic uloborid orb-web form and include cones composed of 
regular arrays of threads beneath the orbs’ lower faces. The web 
building and prey capture behaviors of U. conus (observations of 
YDL) are also described, and descriptions of Conifaber parvus new 
genus, new species and the new species U. conus, U. albolineatus, 
and U. bispiralis are provided (by BDO). 
Study Sites and Methods 
Uloborus conus was found at three localities in Papua New 
Guinea: 1) in lowland wet forest, Gogol Forest Reserve near 
Madang, Madang Province, 2) in a Pandanus swamp (freshwater) 
and a mangrove swamp (brackish) at Buso, Morobe Province, and 
3) in the understory of klinki pine (Araucaria hunsteinii ) plantations 
at 1200 m elevation in McAdam Memorial Park near Wau, Morobe 
Province. Webs were built about 0.5 to 2.0 m above the ground in 
gaps formed by the uppermost, generally vertical branches of small 
shrubs and saplings. They were always found in humid, shaded 
1. Smithsonian Tropical Research Institute, Apartado 2072, Balboa, Panama and 
Department of Zoology, University of Florida, Gainesville, Florida, 32611. 
2. Department of Biology, Virginia Polytechnic Institute and State University, 
Blacksburg, Virginia 24061. 
3. Smithsonian Tropical Research Institute and Escuela de Biologia, Universidad de 
Costa Rica, Ciudad Universitaria “Rodrigo Facio”, Costa Rica. 
4. Museum of Comparative Zoology, Harvard University, Cambridge, Massachu- 
setts 02138. 
* Manuscript received by the editor September 25, 1981. 
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