D. Massemin, S. Clavier & J.-P. Pointier 
Pisidium punctiferum and Eupera viridans from French Guiana 
Figure 1. Geographical localization of French Guiana and mentioned localities from French Guiana. 
these organisais are retained by mesh size of 200-500 
pm], an important hydrobiological study was carried 
out by HYDRECO laboratory during the dry season 
2009 (from September to December), under the 
auspices of the local représentation of the French 
Ministry in charge of environmental questions 
(DIREN Guyane). 
Samplings were conducted by one of us (SC) on the 
entire territory in different habitats (large rivers, mid- 
order streams, small streams named locally “criques” 
and réservoir lakes) using a D-framed hand net (200 
pm mesh size). Samples were collected by sweeping 
the net along the banks. The first centimètres of the 
substratum (organic and/or inorganic) were stirred to 
dislodge attached or buried macroinvertebrates. 
RESULTS 
A total of 125 live specimens of small freshwater 
Bivalvia peaclams species belonging to the 
Sphaeriidae Family and to two different généra, were 
collected in many watersheds (Figure 1, tables 1 & 2) 
and preserved in éthanol 70°. Registered specimens 
were deposited both in public (EPHE, Peipignan, 
France) and private collections (HYDRECO, Kourou, 
French Guiana). The material collected included a 
total of 81 Pisidium punctiferum (Guppy, 1867) and 
44 Eupera viridans (Prime, 1865). 
Identilications of the species were made according 
to spécifie conchologically characters (Kuiper, 1983) 
and original descriptions of Guppy (1867) for P. 
punctiferum and Prime (1865) for E. viridans. 
Diagnose of the striate peaclam P. punctiferum 
was established according to the following criteria: 1/ 
The average size when adult is around 3 mm in length 
and 2.5 mm in height; 2/ The shell is oval and thin, the 
anterior valve is shorter and angulated in its posterior 
part; 3/ The test is diaphanous, finely striate 
concentrically and covered with numerous granular 
points, which are finer and more crowded on the 
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