Fróðskaparrit - 01.07.2004, Side 70

68
SPIDERS (ARANEAE) IN THE FAROE ISLANDS: A REVISED CHECKLIST
AND AN UPDATE ON INTER-ISLAND DISTRIBUTIONS
found on 6 islands and in 8 locs.
Xysticus cristatus (Clerk, 1757). First
records for Koltur (5 a), Kunoy (Kl,
K8, and KIO, total 13 c o* 3 9 9) and
Viðoy (loc. 47, 1 cr 2 9 9 ). Widely distrib-
uted and now found on 9 islands (incl. the
northern islands; cf. Bgd 1928) and in at
least 29 locs, though nowhere in large num-
bers.
Discussion
The Faroes have a relatively low species
richness which is presumably mainly relat-
ed to their remoteness, small area, narrow
range of habitats, prevailing oceanic cli-
mate and the relatively short period of time
that the islands have been open to colonisa-
tion since the latest glaciation (e.g. Bengt-
son, 1982; Enckell, 1989). The number of
spider species recorded in the islands will
(as in any given area), for several reasons,
continue to increase with sampling effort
and ongoing immigration. Thus, Brænde-
gaard’s (1928) list of 43 species was based
on the combined efforts of a number of col-
lectors, whose options (seasonally and geo-
graphically) were usually limited for logis-
tic reasons. When Holm (1980) in 1966
spent about a month (25 June-20 July) in
the Faroes, he visited 5 of the islands and
employed various collecting methods.
Among ca. 1,500 specimens collected and
idenifíed he found 15 species not previous-
ly recorded (he claimed 16, but one of them
(P. variegata {globosa)) had in fact previ-
ously been reported). The summer collect-
ing in 1978 (largely pitfall trapping but in-
cluding other methods as well, see Bengt-
son and Hauge 1979), covering effectively
the whole archipelago, yielded ca. 1,600
adult specimens, and included 7 species
recorded for the first time. The present pit-
fall material (ca. 10,000 adult specimens),
for the first time including significant col-
lections made outside the summer season,
added 10 species to the Faroese list viz. the
comb-footed spider C. guttata, the money
spiders A. gulosa, A. ramosa, A. subtilis, C.
prudens, H. bituberculatum, M. whymperi,
and O. melanopygius, the wolf spider A.
alpigena, and the crab spider O. atomaria.
With the above-mentioned species and the
present indoor-finds of the cobweb spider
T. atrica and the ord-weavers A. diadema-
tus and A. quadratus, and previously pub-
lished fmds of three more anthropochorous
spiders viz. P. phalangioides , N. umbrati-
ca, and U. plumipes the number of species
found in the islands has increased consider-
ably (> 20 %) since the papers by Bengtson
and Hauge (1979) and Holm (1980) were
published. In the former paper the authors
had access to the information given by
Holm to Ashmole (1979) and they claimed
that 67 (instead of 68) species of spiders
had been recorded in the Faroes, although
the paper only listed 65, the reason being
that C. concinna, P. montanum, and W. ob-
tusa had been left out by mistake (Bengtson
and Hauge, 1981). On the other hand they
included an old record of Erigonoplus (Tri-
chopterna) globipes (L. Koch, 1872) from
Tórshavn (see Brændegaard, 1928) in their
list, not knowing that Holm (1980: 111,
114) had inspected the two specimens, that
were being kept in the collections of the the
Museum of Zoology, Copenhagen, and