black sea red data book - Department of Biology

Synonyms: None.
Common names: None.
Hesionides arenarius (Friedrich, 1936)
Order NEREIMORPHA
Family HESIONIDAE
Taxonomic description. One of three species of Hesionidae in the Black Sea.
Length from 1.7 to 3.0 mm, with brownish pigmentation, up to 19-25 segments, eyes
absent. Pygidium with two distinctly separated anal lamellae, which do not overlap
but distally broaden and fan-shaped. Two long, threadlike anal cirri
IUCN Status
World level:
Black Sea Regional level:
Subregion level: EN (Ukrainian and Romanian sectors), VU (Romanian sector)
Distribution. Hesionides arenarius has a wordwide distribution in tropical and
subtropical beaches; it also inhabits boreal regions. In the Black Sea, it was reported
on the Bulgarian, Romanian and Ukrainian shelves. This species belongs to the
characteristic forms of the interstitial meiofauna of bare-washed sandy beaches.
Limiting factors. Limiting factors are the size of sand grains, the pollution of the
sandon the sea shore, and man-made changes in the granulometric composition of
sand.
Biology. Species of Hesionides form a common element in the interstitial animal
community.
Population trends. A sharp decline in population numbers (80-90%) since the
1980s.
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