Guinean leaf-dwelling pholcids
(published in J. Nat. Hist. 43 (2009): 2491-2523. PDF)

Many tropical pholcid spider species are morphologically and behaviourally adapted to life on the underside of green leaves. The taxonomy of these cryptic spiders is partly poorly known, and almost nothing is known about their biology. Leptopholcus guineensis, shown on the right, was previously known from only two female specimens: the types collected in 1937.

During a trip to Guinea in 2008, we collected a total of seven leaf-dwelling species representing six genera, with up to five species per locality (Forêt Classée de Diéké).
Shown below are: Crossopriza cylindrogaster (a), Nyikoa limbe (b), Leptopholcus tipula (c), Spermophora dieke (d), Pehrforsskalia conopyga (e), and Pholcus kakum (f). At the level of genera, this is comparable to the diversity of leaf-dwelling pholcids reported by Deeleman-Reinhold (1986a) for Indonesia (seven genera).leaf-dwellers

crossoprizaMost remarkable is Crossopriza cylindrogaster, a species described by Eugene Simon over 100 years ago based on a single female specimen and never mentioned again in the scientific literature. It has an inverted resting position (dorsal side pressed against the leaf; see above), tetrahedral egg-sacs, modifications of the lateral eyes that appear like additional lenses ("pe" in the figure shown here), and lampshade webs with or without ‘ornaments’ (puffs of silk) (below).