264
H. Michaelis and W.J. Wolff
Bane d'Arguin - Sandy Flats (Table 12.2). Figure 12.4 shows which of the 41
species playa dominant role. Seoloplos sp. 1 is most widely spread. The most
abundant species, Hydrobia cf. ulvae and Ampelisea brevieornis, are low in
frequency of occurrence but nevertheless belong to the group of four species
with the largest biomass.
Bane d'Arguin - Seagrass Beds (Table 12.2). The occurrence of 93 species
was ascertained. Numerous species participate in the different aspects of
dominance (Fig. 12.5). Nine species reach a frequency of occurrence of 60 %
or more, with Anthuridae sp. 1 and Loripes laeteus occurring in all samples.
Seven species together represent more than 60 % of all individuals with L.
laeteus taking the largest share. Marphysa sanguinea has the highest biomass.
Seoloplos sp. 1
Diopalra neaDollilana
Loripes
Heleromaslus filiformis
Anthuridae sp. 1
Euclymene IOderilziana
Fig. 12.4. Habitat "sandy fiats"
on the Banc d' Arguin. Species
Ampslisca brevicomis
dominant in frequency of
Macroclymene monilis
Uea langeri 1 - _ _ _ _
occurrence (% of stations),
Hydrobia cl. ulvae ~_~_~_ ...,.--._~~-"
abundance (% of total) and
o
20
40
60
80
100 %
biomass (% of total)
Anthuridae sp. 1
Lon."es lacleus
Diopalra neapolilana
Perinereis eullrifera
Cymadusa hirsula
Heleromaslus filiformis
Abra
He/eromas/us filiformis i- - - - - ---..
Anthuridae sp. 1 ~ _ _ _ _ -----'''I"-_-+_--I
Marphysa sanguinea .,... _ _
Loripes laclsus +--_~
Perinereis eultrifera 1 - - - - -
Pelaloproelus lemeola +---___ - ___ "-_-I-~--l
o
20
40
60
80
100 %
Fig. 12.5. Habitat "seagrass
stands" on the Banc d' Arguin.
Species dominant in frequency
of occurrence (% of stations),
abundance (% of total) and
biomass (% of total)