Fróðskaparrit - 01.07.2004, Síða 47

FØROYSKAR VATNKLUKKUR
45
the status of most species that had been re-
ported, and draw attention to records re-
quiring confirmation. This paper also pro-
vides an opportunity to update the checklist
in terms of new understanding of the status
of several species.
Results
Species commentary
These commentaries cover both old records
and data acquired recently, with a critical
appraisal of the basis for old records. Only
those species that have been emboldened
can be regarded as confirmed for the
Faroes. The names follow recent checklists
(Hansen, 1999; Lobl andSmetana, 2003).
HALIPLIDAE
Haliplus fulvus (Fab.). West (1930)
recorded this species from Suðuroy, San-
doy and Eysturoy. Found at three localities
(10%) in 2004. The habitat, still water lakes
over sand, often in deeper water in associa-
tion with sparse vegetation, is typical of its
occurrence in general.
DYTISCIDAE
Agabus bipustulatus (L.). Sharp (1900)
identified “Agabus bipustulatus” from ma-
terial taken by N. Annandale in June 1900
near Tórshavn; Sharp (1903) also reported
“Agabus bipustulatus var.” taken by An-
nandale in August 1903, also at Tórshavn.
Nielsen (1908) referred to this species as
Agabus alpestris Heer, as did Mjðberg
(1917). Walker (1938) referred to solieri
only, and Bengtson (1981) referred to
Agabus solieri Aube, but equated it to “A.
bipustulatus Sharp”. Drotz et al. (2001)
have convincingly demonstrated that
solieri is no more than a form of bipustula-
tus that can be produced under altitudinal
stress. A. bipustulatus is the only large div-
ing beetle in the Faroes. The female is of
the dull form typical of north-west Europe,
as was noted by Holdhaus (1911), and the
body shape and size are those of solieri. A.
bipustulatus, including many young larvae,
were found in 57% of samples in June
2004, mainly in small, still or slowly mov-
ing water bodies with some submerged
vegetation. The islands from which it is
known are Suðuroy, Streymoy, Eysturoy,
Sandoy, and Vágar.
Hydroporus erythrocephalus (L.). This
was originally recorded by Mjoberg
(1917), who described a new variety, faro-
ensis. This was a form of female that ap-
pears matt because of intense microreticu-
lation of the upper surface, by priority hav-
ing the name deplanatus Gyllenhal. It is the
commonest form of female in Scotland, but
is replaced further south by the female form
with the same reticulation as the male.
Miller (2003) has demonstrated that such
female cuticular features have evolved on
several occasions in Dytiscidae, being a de-
vice to resist copulation. This species is
typical of deeper, still water in small water
bodies, usually on peat and among vegeta-
tion.
West (1930) noted it from Streymoy,
Viðoy and Suðuroy, and described it as lo-
cal. In June 2004 it was found in 23% of
samples.
Hydroporus memnonius Nicolai. West