Two species of the genus Pocadicnemis (Araneae, Linyphiidae), P. pumila (Blackwall) and P. juncea (Locket & Millidge) have been reported from Scandinavia. In order to find out the distribution and differences in the habitat, all specimens of Pocadicnemis from the author's collection, the collection of Sven Almquist, the Swedish Museum of Natural History (including the collection of Tullgren), and the Zoological Museum of Lund have been checked

Jonsson, Lars J.

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Arachnol. Mitt. 9:46-48  Kurzmitteilungen  Basel, Juli 1995 Lars  J.  JONSSON:  The  distribution  and  habitat  of . Pocadicnemis pumila and P. juncea(Araneae, Linyphiidae) in Sweden Two  species  of  the  genus  Pocadicnemis  (Araneae,  Linyphiidae), P.  pumila  (BLACKWALL) and  P.  juncea (LOCKET & MILLlDGE) have been reported from Scandinavia. Prior to the article of MILLlDGE (1975) the two species were believed to be only one, i. e.  P. pumila. The habitat and distribution of the two species are insufficiently known.  P.  pumila has been reported several times from Sweden (e. g. TULLGREN 1955), but P.juncea only  from the southernmost part (HOLM 1977, ALMOUIST 1982). In  order to find  out the  distribution  and  differences  in  the  habitat,  all specimen of Pocadicnemis from my own collection, the collection of Sven ALMOUIST, the Swedish Museum of  Natural History (including the collection of TULLGREN), and the Zoological Museum of Lund has been checked. Surprisingly, Pocadicnemis juncea has been found only in southern  most Sweden, i. e. Skane (Scania), where it is common. In Skane nearly all findings of P.  juncea are from open to semiopen ground, with at least some herbs or grasses. It has been found on ground in  biotops  of  different  humidity,  but it  seems  to  be  most common  in wetlands.ln Skane on localities with a closed canopy, or  with wet  and acidic Sphagnum, or on dry sandy ground, P. pumila is normally the only species of the genus to be found. Of  special interest are two collections made by Sven ALMOUIST. In the National Park Area of Stenshuvud he collected P.  juncea among grasses and mosses in a wet meadow, and P. pumila nearby among litter on ground in woodland. In Holmeja he collected on a meadow  and in spruce plantations of  different ages (ALMOUIST 1982). On the ground in meadow and spruce plantations  (4  and  8  years  old)  all  Pocadicnemis  turned  out  to  be P.juncea. P. pumila is a common species that has been found in most provinces throughout Sweden. North of 56°N  it has been found in  many different 46 biotops, including marshes and other more or less sunexposed places with grasses and herbs. Males of both species are normally found early in  summer.  A clear difference in seasonal activity of different years is probably due to different weather, e. g. in 1991, when the early summer was very cold, males did not appear until July in Skane. Reports of the habitat of Pocadicnemis are scarce, also from Central Europe and the British Isles. In HEIMER & NENTWIG (1991) P.  juncea is reported living "meist aut freien Flachen, feuchtlebend" and P. pumila  as "ahnlich  juncea, auch in  Waldern". MARTIN (1991), who worked with a huge  material  from  the  former  GDR  (DDR),  has  proposed  so  called "6kograms". By looking at those, one can conclude that P.  juncea lives on open  and  moist to  wet  habitats,  and  that  it  has  been  recorded  from meadows and mires: usually it is found among mosses, but also among grasses, herbs, and litter. P. pumila on the other hand seems to be a more eurytopic and common species. PLATEN (1984) in Berlin found  P. juncea only in wetiands, but P. pumila occurred in several different biotops, both wet and dry ones.  MAURER & H.A.NGGI  (1990)  reported  P.  juncea as photo- and hygrophil, found in meadows with a rich herb layer, on ground under  thickets,  in  moist  meadows,  and  among  vegetation  on  banks. HARVEY (1990) reported P. juncea as "common in a variety of situations such as grassland, marsh and saltmarsh", andP. pumilaonlyfrom "relic wet heath habitats". Probably P.  pumila is restricted in the southern part of its distribution area to biotops with a canopy, orthose which are more or less acidic or dry. P.  pumila seems to  be the  species that can  withstand less favourable conditions, and thus being more eurytopic and more adapted to a northern habitat. Acknowledgments: I thank Torbjorn KRONESTEDT (Swedish Museum of Natural History) , Lennart CEDERHOLM (Zoological Museum of Lund), and Sven ALMOUIST for kindly loaning to me specimens of Pocadicnemis. REFERENCES ALMOUIST, S.  (1982): Spindeldjursfaunan i granplanteringar i sodra Skane. - Ent Tidskr. 103: 97-105 HARVEY P.  R.  (1990):  Essex Spider Group:  Report for 1989. - News. Br.  Arachnol.  Soc. 57: 3-5 47 HEIMER, S.&  W. NENTWIG (1991): Spinnen Mitteleuropas. Paul Parey, Hamburg & Berlin. 543 S. HOLM, A.  (1977): Kullabergs spindlar. - Kullabergs natur 15: 1-29 MARTIN,  D.  (1991):  Zur Autokologie  der Spinnen  (Arachnida:  Araneae)  I.  Charakteristik der Habitatausstattung und Praferenzverhalten epigaischer Spinnenarten. -Arachnol. Mitt. 1: 5-26 MAURER,  R.  & A.  HANGGI (1990): Katalog der Schweizerischen Spinnen. Catalogue des Araignees de Suisse. Doc.  Faun. Helv.  12, Centre  suisse de cartographie de la faune (CSCF), Neuchatel. MILLlDGE, A. F. (1975): Re-examination ofthe erigonine spiders"  Micrargus herbigradus' and 'Pocadicnemis pumila" (Araneae: Linyphiidae). - Bull. Br. Arachnol. Soc. 3:  145-155 PLATEN, R. (1984): Okologie, Faunistik und Gefiihrdungssituation der Spinnen (Araneae) und Weberknechte(Opiliones) in Berlin (West) mitdem Vorschlag einerroten Liste. -Zool. Beitr. N. F. 28: 445-487 TULLGREN, A.  (1955): Zur Kenntnis schwedischer Erigoniden. - Ark. Zool. 7: 295-389 Lars J. JONSSON, Basgranden 45, S - 224 68 Lund, Sweden 48 

The distribution and habitat of Pocadicnemis pumila and P. juncea (Araneae, Linyphiidae) in Sweden

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