Arne Fjellberg

Three species of Isotoma (Collembola, Isotomidae) based on morphology, isozymes and ecology

Morphological markers and isozymes were used for identifying three presumed species of the Isotoma genus. Morphological traits separated three taxa of the genus. 10 isozymes determined by at least 11 loci were analysed from each taxon, and 2 loci were taxon‐specific, supporting the hypothesis that the three taxa represented three species. The genetic variation found within the taxa measured as fraction of polymorphic loci at the 99% level was 0.82, 0.55 and 0.55 with the corresponding observed heterozygosity 0.15, 0.09 and 0.12. Two populations of the same taxon from Denmark and Norway, respectively, were very closely related. Additional ecological criteria, obtained from a literature survey, also revealed pronounced differences between the three taxa. Due to these facts three distinct species are proposed, namely I. anglicana Lubbock 1862, I. riparia Nicolet 1841 and I. viridis Bourlet 1839.

Abundance of Tundra Arthropods in Spitsbergen

The late summer abundance of higher taxonomic units of arthropods on different types of coastal tundra in Spitsbergen (approx. 79°N, 12°E) was assessed by means of suction sampling of vegetation and litter and soil samples. Acari and Collembola comprised 96—99 % of the total number of arthropods and some Araneae and Diptera and a few Hymenoptera were regularly recorded. The total abundance (ind./m2) varied between 42—63,000 on lichen covered tundra, 268,000 on wet moss tundra, and 518,000 on grassland. There were considerable similarities in the abundance of major groups of arthropods between the Spitsbergen tundra and high alpine grounds in southern Norway, although in the former area some groups were absent.

Revision of European and North African Folsomides Stach with special emphasis on the Canarian fauna (Collembola: Isotomidae)

The genus Folsomides Stach, 1922 is redefined and given a narrow definition based on a limited set of consistent morphological characters: Position and distribution of tergal macrosensilla, chaetotaxy of mouth region, tibiotarsi, ventral tube and furca. Eighteen new species are described from the Canary Islands: semiparvulus sp. n., xerophilus sp. n., vinosus sp. n., cumbrosus sp. n., unicus sp. n., terrus sp. n., pocosensillatus sp. n., nigrocellatus sp. n., teno sp. n., oromii sp. n., ononicolus sp. n., graminis sp. n., famarensis sp. n., pinicolus sp. n., intermedius sp. n., tonellus sp. n., supranubius sp. n. and analuisae sp. n. The following European/African species are redescribed: parvulus Stach, portucalensis Gama, angularis (Axelson), cf. petiti Delamare, lawrencei Gers & Deharveng, cf. zairensis Martynova, nanus Ellis and centralis (Denis). Highly discriminate species characters are found in maxillary palp, tibiotarsal chaetotaxy and distribution of tergal microsensilla. A number of species are removed from Folsomides, and Subisotoma Stach, 1947 is given generic rank.

The invertebrate fauna of anthropogenic soils in the High-Arctic settlement of Barentsburg, Svalbard

The terrestrial environment of the High Arctic consists of a mosaic of habitat types. In addition to the natural habitat diversity, various human-influenced types may occur. For the resident invertebrate fauna, these anthropogenic habitats may be either unusually favourable or detrimental. In the town of Barentsburg, Svalbard, soils were imported for the greenhouses from southern Russia. These soils were subsequently discarded outside the greenhouses and have become augmented with manure from the cowsheds. Both the greenhouse and the cowsheds are now derelict. This site represents an unusually nutrient-rich location with considerable development of organic soils, in stark contrast to the naturally forming organic soils in Svalbard, which are typically thin and nutrient poor. Few previous studies have examined the soil invertebrate communities of human-disturbed or -created habitats in the Arctic. In an often nutrient-poor terrestrial environment, it is unclear how the invertebrate fauna will react to such nutrient enhancement. In these soils, 46 species of invertebrates were determined. Eleven species have not been recorded from other habitats in Svalbard and are hence likely to have been introduced. The native species assemblage in the anthropogenic soils was not atypical for many natural sites in Svalbard. Despite the enriched organic soils and highly ameliorated winter temperature conditions, the soil invertebrate fauna biodiversity does not appear to be enhanced beyond the presence of certain probably introduced species.

Northern species of Onychiurus Gervais, 1841, subgenus Archaphorura Bagnall, 1949 (Collembola: Onychiuridae)

[The morphology of larval ventromentral plates of two taxa in the Chaetolabis subgenus of Chironomus Meigen, C. macani Freeman and C. ochreatus Townes, has been studied by light and scanning electron microscopy. The plates of these taxa are shown to differ in a number of ultrastructural characters, but still share features in common with representatives of other Chironomus subgenera. Taxonomic implications of these findings are discussed., Samples from Scandinavia, Svalbard, Canada, Alaska, and NE. Siberia have been examined, and the following species are described or commented: absoloni (Borner, 1901), groenlandicus (Tullberg, 1876), schoetti (Lie-Pettersen, 1896), ursi Fjellberg, 1984, aborigensis sp. n. (NE. Siberia), alnus sp. n. (NE. Siberia), interruptus sp. n. (NE. Siberia), nataliae sp. n. (NE. Siberia), nudus sp. n. (Alaska, Yukon), pingicolus sp. n. (Alaska), and reversus sp. n. (Alaska, Yukon). An identification key is given.]

Microarthropod communities of industrially disturbed or imported soils in the High Arctic; the abandoned coal mining town of Pyramiden, Svalbard

The terrestrial environment of the High Arctic consists of a mosaic of habitat types, both natural and anthropogenic. At the abandoned coal mining town of Pyramiden, Svalbard, topsoil was imported from southern European Russia. This, and further industrial disturbance in the town, offers new opportunities for the native invertebrate fauna, but may also introduce alien, potentially invasive, species. Few studies have examined anthropogenic habitats in the High Arctic. But increasing activity, including industry and tourism, requires an understanding of the responses of the Arctic to such pressures. The microarthropod communities observed in the settlement were substantially different from the natural tundra. In the settlement, nine species of mesostigmatid mite occurred (three new records for Svalbard; Dendrolaelaps foveolatus) and two additional not identified to species (Halolaelaps sp., Arctoseius sp.), 26 species of Collembola (12 not seen in the natural tundra close to Pyramiden) and two new records (Thalassaphorura debilis and Desoria tigrina), but only five Oribatida. This is set against 8, 20 and 24 species respectively for Mesostigmata, Oribatida and Collembola from natural tundra in the vicinity. The imported soils remain to be yet fully exploited by the native microarthropod fauna. Taxa disparities may result from differential mortality during collection and shipping of the soil, and subsequent colonisation. While none of the introduced species appear to be invasive, responses to climate change scenarios are difficult to project. Understanding of alien species and the timespans required for colonization by native faunas are of importance for remediation and reclamation projects in polar regions.

ON THE COLLEMBOLA, ARANEAE AND GAMASIDA FROM THE KINNVIKA REGION OF NORDAUSTLANDET, SVALBARD

Coulson, S.J., Fjellberg, A., Snazell, R., Gwiazdowicz, D.J., and Ávila‐Jiménez, M.L., 2011. On the Collembola, Araneae and Gamasida from the Kinnvika region of Nordaustlandet, Svalbard. Geografiska Annaler: Series A, Physical Geography, 93, 253–257. DOI: 10.1111/j.1468‐0459.2011.00425.x Abstract The Collembola, Araneae and gamasid mite fauna from the vicinity of Kinnvika on the island of Nordaustlandet in the Svalbard archipelago are described. Few records of the invertebrate fauna from this remote and climatically extreme region exist. Twenty‐four species of Collembola were identified, of which three were new records for Nordaustlandet. None were new records for Svalbard. In addition, seven species of Araneae, three of which were new records for Nordaustlandet, and five species of gamasid mite, all new to Nordaustlandet, were collected. All invertebrates collected were already known from locations on the west coast of Spitsbergen. These records supplement the scarce current terrestrial invertebrate data for this region and contribute towards the baseline data for this region proposed to become an Arctic environmental reference area.

Tibiotarsal chaetotaxy in Tullbergiinae (Collembola: Onychiuridae)

Six types of tibiotarsal chaetotaxy are recognised among genera of the subfamily Tullbergiinae. The most complete chaetotaxy is found in the nearctic species Thllbergia clavata Mills, while the most reduced type is displayed by many species of Mesaphorura and related genera.

Revision of the European species in the Isotoma olivacea-group (Collembola: Isotomidae)

The paper includes the following species: Isotoma antennalis (Bagnall, 1940), I. blufusata Fjellberg, 1978, I. divergens Axelson, 1900, I. fennica Reuter, 1895, I. germanica Huther & Winter, 1961, I. hiemalis Schott, 1893, I. infuscata (Murphy, 1959), I. nanseni Fjellberg, 1978, I. neglecta Schaffer, 1900, I. nivea Schaffer, 1896, I. olivacea Tullberg, 1871, I. propinqua Axelson, 1902, I. ruseki n.sp., I. tigrina (Nicolet, 1842), I. tshernovi Martynova, 1974 and I. violacea Tullberg, 1876. A key for separation of the species is given.

Revision of the genus Agrenia Börner, 1906 (Collembola: Isotomidae)

The formerly monotypic genus Agrenia is redescribed. The holarctic type species Isotoma bidenticulata Tullberg, 1876 is redescribed and a lectotype is designated. Six new species are described: polymorpha sp. n. (N. America), pilosa sp. n. (Japan), agilis sp. n. (N. America), cyanura sp. n. (N. America), riparia sp. n. (Holarctic) and atroviridis sp. n. (N. America). The genus is recognised by a set of apomorphous characters: Absence of sublobal hairs on the maxillary outer lobe, presence of dorsal tubercles on dens, a long subapical macrochaeta on inner side of dens, and presence of a tunica on unguis. Sexual polymorphism (epitoky) and cyclomorphosis are reported in several species. Neutralization of male secondary sexual characters are observed in some reproductive specimens. Distribution of the genus covers the arctic, boreal and montaneous parts of the northern hemisphere.