Fróðskaparrit - 01.01.1998, Blaðsíða 274

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INSECT FAUNAS AT LANDNÁM: A PALAEOENTOMOLOGICAL STUDY
AT TJØRNUVÍK; STREYMOY; FAROE ISLANDS
Taxon S19 S3 S2 Sl
Carabidae
Notiophilus biguttatus (F.) 2
Loricera pilicornis (F.) 1
Trechus obtusus Er. 3
Bembidion bruxellense Wesm. 2
Patrobus septentrionis (Dej.) 1
Patrobus sp. 1
Trichocellus placidus (Gyll.) 1
Dytiscidae
Hydroporus gyllenhali Schdte. 2
H. pubescens (Gyll.) 1 2
H. nigrita (F.) 1
Hydrophilidae
Helophorus flavipes (F.) 1 4
Helophorus sp. 1
Cercyon sp. 2
Megasternum boletophagum
(Marsh.) 1 7
Anacaena globulus (Payk.) 5
Staphylinidae
Omalium rivulare (Payk.) 5
Xylodromus concinnus (Marsh.) 1
Olophrum fuscum (Grav.) 1 1
Lesteva heeri Fauv. 2 6
L. longoelytrata Goez. 2 1
Lesteva sp. 1 1 1 5
Ochthephilus omalinus (Er.) 15
Stenus nitidiusculus Steph. 5
Stenus sp. 1 5
Othius angustus Steph. 1 1
Othius sp. 1
Philonthus sp. 1
Quedius umbrinus Er. 5
Quedius sp. 2
Aleocharinae gen. indet. 3 1 16
Elateridae
Hypnoidus riparius (F.) 1
Byrrhidae
Simplocaria semistriata (F.) 1 1
Scarabaeidae
Aphodius lapponum Gyll. 1
Curculionidae
Apion haematodes Kirby 1
Notaris aethiops (F.) 1
Ceutorhynchus contractus
(Marsh.) 1
Table 1. Insect remains from samples across landnám
at Tjørnuvík, Stremoy, Faroe Islands
Talva 1. Skordýraleivdir frá royndum í landnámstíð í
Tjørnuvík.
in Iceland (Buckland et al. 1986; 1991a;
Sadler and Skidmore 1995), where in-
creased eutrophic habitat diversity around
farms and hayfields allowed successful
colonisation by many accidental inverte-
brate immigrants and the expansion of sev-
eral apparently native species, once virtual-
ly restricted to bird cliffs, into man-made
habitats. The Tjørnuvík site provides Faroe
with a particularly striking example of a
similar event, adding the fossil dimension
to Enckell’s (Enckell, 1985; Enckell et al.
1987) work with the modern earthworm
fauna. Beneath the gravel horizon, insect
preservation was poor, and sample Tjl/3
contained only ten individuals of six taxa.
The long pre-landnám sample Tjl/19 was
worse, with four individuals of three
species. The small water beetle, Hy-
droporus nigrita occurs in peaty pools and
cold streams (Nilsson and Holmen 1995),
where Helophorus flavipes may also be
found (Friday 1988). The staphylinids of
the genus Lesteva are found in wet moss
and on grassy heaths (Bengtson 1981).
Sample Tj 1/19 contains some suggestion of
more eutrophic conditions, perhaps adja-
cent bird cliffs, in the two individuals of the
hydrophilid genus Cercyon. The sites in
Saksunardalur, 5 km to the south (Buckland
et al. 1998a) provide a much more exten-
sive pre-landnám faunal list, although Tjør-
nuvík does confirm the presence of a
species of Cercyon, suspected on the Myki-
nes evidence (Buckland et al. 1998.b).
The sample of the gravel horizon inter-
preted by Jóhansen (1971) as a result of
flooding by the small stream in the valley
contained a large fraction of coarse angular