New Swedish records of Feather-wing beetles (Coleoptera, Ptiliidae), and a discussion of two regionally extinct species MIKAEL SORENSSON Sörensson, M.: New Swedish records of Feather-wing beetles (Coleoptera, Ptiliidae), and a discussion of two regionally extinct species. [Nya fynd av fjädervingar (Coleoptera, Pti- liidae) i Sverige, samt en diskussion kring två regionalt utdöda arter.l - Entomologisk Tidskrift 121(4): 181-188. Lund, Sweden 2000. ISSN 0013-886x. New data on 22 North European species of Feather-wing beetles (Coleoptera, Ptiliidae) are presented. Actidium coarctatum (Haliday) and Actinopterytr fwcicola (Allibert) are consi- dered extinct in Sweden as well as in the Baltic region, the possible reasons for which are discussed. Unknown large scale processes seem to be responsible for their overall retreat in northern and northwestern Europe. A. coarctatum should be added to the Danish list. The type material of Ptilium elongatum Thomson (= Actidium coarctatum (Haliday)) is discus- sed. Twenty four new provincial records are added to the Swedish catalogue (Lundberg 1995), among them some rare species. The fourth locality known in the world for Oligella nana (A. Strand) as well as the southemmost record of Baranowskiella ehnstromi Sörens- son in the Palearctic region is reported. M. Sörensson, Department of Systematic Zoology, Lund University, Helgonavägen 3, SE- 223 62 Lund. Sweden. E-mail: <mikael.sorensson@ zool.lu.se> Introduction Since the publication of the last report on Swe- result of directed, local inventory work with the dish and North European Featherwing beetles aid of window traps. Window traps may be quite (Sörensson 1994) additional finds as well as new efficient for trapping ptiliid species with high or data have increased our understanding of the moderate dispersal capacity, i.e. species tied to geographical distribution, dynamics and ecology more or less ephemeral habitats, but is less suited of the group. Besides new provincial records for species inhabiting more stable environments. from Sweden this paper focuses on two species However, trapping is also dependent on the previously recorded from the Baltic region but arrangement and location ofthe trap. For faunis- now considered extinct. There is currently a great , tic inventoiies ofPtiliidae traps usually has to be need for updating the taxonomic and faunisticr supplemented by directed search efforts, primari- knowledge of European Ptiliidae. It is my inten- ly by the means of a sieve. In a few cases, e.g. tion to presenl similar revisionary notes concer- gents Actidinm Matth. and Nanoselline species ning Ptiliidae on a Central European or Pan- such as Baranowskiella ehnstromi Sörensson European basis in the future. (see below), manual search in specific habitats is required. If not otherwise stated the specimens referred Material and collectors to below are preserved in the collection of the Private as well as public collections of Ptiliidae original collector. New provincial records are were investigated. Many recent records are the marked with an asterisk (*). 181 Mikael Sörenssr.tn Ent. Tidskr. 121 (2000) Collectors and/or private collections: Göran Andersson (GA), Peter Cederström (PC), Alan Dufberg (AD), Bertil Ericson (BE), Bo Henriks- son (BH), Nicklas Jansson (NJ), Åke Lindelöw (AL), Roger Pettersson (RP), Henrik Wald6n (Hw). Museum collections: BMNH = British Muse- um of Natural History in London; NMG = Mu- seum of Natural History in Gothenburg (Natur- historiska museet i Göteborg); RM = Museum of Natural History in Stockholm (Naturhistoris- ka riksmuseet i Stockholm); ZML = Zoological Museum in Lund (Zoologiska museet i Lund). Species now extinct in the Baltic region Ac tidium c o arctatum (Haliday) Species of Actidium Matthews are primarily found in the littoral zone of fresh and saline wa- ter. Several species have been recorded from shores of rivers, ponds and lakes but also from coastal areas in tropical and subtropical latitu- des. From Sweden only the halophilous Acri- dium conrctatum (Haliday) has been recorded (Fig. 1). It is a western Palearctic species widely distributed along the coasts in the northeastern Atlantic region. It is rather common by the Mediterranean sea and in North Africa. Towards the north it becomes much sparser, and at coasts in northern Europe it is considered very rare. Fig. L Actidium coarctatum (HaLiday). Bodylength: 0.65 mm. lllustration M. Sörcnssort. As with Actinopteryx fucicola (Allibert) (see below) this halophilous, seashore-dwelling spe- cies has in Scandinavia long been known only (Thomson 1855). It was an attempt to catch up liom nineteenth century records. Swedish cata- with the modern results concerning nomenclatu- logues, from Grill (1896) and onwards, records re, faunistics and taxonomy recently presented it from the province of Skåne (Scania) in south- by continental authors such as Erichson, Gill- ernmost Sweden. West (1940-41) mentioned an meister and Motschulsky. The work was the re- old find from Copenhagen but doubted its Da- sult of Thomson's own collecting experience nish origin, which caused subsequent authors to and knowledge of the group, although he leaned erroneously delete it from the Danish list of heavily on the authorities mentioned. Coleoptera (e.g. Hansen 1996). Scandinavian In this paper Thomson briefly mentioned P records sometimes went under the name Ptilium elongatum as having been found "under a stone elongatum Thomson. Incidently Thomson's and by a dunghill in the Lund vicinity". Collector, Haliday's names were published the same year date or exact locality were not mentioned. In (1855), but Haliday's name has been considered "Skandinaviens Coleoptera" (Thomson 1862) as having priority since. he slightly altered the phrase to: "Rare. Found at Thomson described Ptilium elongatum in a Lund under rotting organic matter", while in the paper presenting a monographic review of the supplement (Thomson 1867) he forwarded com- Swedish species of Trichopterlgia (= Ptiliidae) pletely new information: "found at Malmö by 182 Ent. Tidskr. 121 (2000) Feather-wing beetles in Northern Eurctpe lector L. Stenberg". Thus there seemed to be two elongatum for comparison" [with P. coarctatum finds of P. elongatum, one near Lund and one Halidayl. The Stenberg-specimen ref-erred to near Malmö. This information was later reite- above is obviously identical to that specimen. rated by Grill ( 1896). The find near Lund, about Matthews' wording "unique" sounds odd since I0 kilometres inland from the coast of the Baltic there were more than one Swedish specimen Sea, seems extraordinary since this halophilous known at the time. It could possibly indicate that species is generally known to occllr on the sea- the original Råby-specimen was already lost. shore under seaweed and other rotting organic The pair of pins in the upper row are similar matter. However, in Great Britain (Fowler 1889; to each other, stout, contemporary with large Hyman & Parsons 1994) and Ireland (Matthews heads. The cardboards are triangular but with 1883), and in southern Europe (Lundberg et al. the apex cut off in a characteristic manner. The 1987) A. coarctatum has occasionally been left cardboard has three specimens irregularly found off the coast in farmyards and hotbeds, in mounted while the right has only one. All speci- organic refuse along rivers, and even among mens are well preserved and belong to Actidium litter and rotting leaves. coarctatum. No labels are present. These pins The main collection ("Berlin-collection") of and mounts are identical to a third pin standing C.C. Thomson in Lund (ZML) contains 4 old in Thomson's collection of doublettes. This pin pins standing 2+2 in two rows under "Ptilium holds three well preserved specimens of A. elongatum" (Thomson's handwriting). The lo- coarctatum, irregularly mounted, and an elon- wer right is a very thin contemporary pin with a gate label in Thomson's handwriting (pencil) small, tiny triangular cardboard attached (origi- with interesting information: "Ptilium elonga- nal Thomson mounting). Unfortunately no spe- tum Tång" (Tång = seaweed). At this time ento- cimen is present. The pin bears an old, square mologists generally only labelled the first pin in label with "Råby stg 914" written in ink a row. The identical pins and mounts suggest (Thomson's style). Råby is a small village just that all three pins belong to one and the same outside Lund. The abbreviation "stg" is not de- collecting series. The word "Tång" indicates cipherable but could possibly be "stallgödsel" that the specimens probably were collected in (dunghill). Thomson often abbreviated names, Sweden, possibly somewhere along the Scanian since his labels were very small. coastline, under seaweed. The lower left pin is younger, black and In collectio Boheman (RM) a filth pin bea- rather thick. lt bears an almost perfect specimen ring a Swedish specimen of A. coarctatum was of Actidium coarctatum mounted under a plastic discovered under "Ptilium elongatum". It is "window" on a larger hexagonal, double card- mounted on a very small, square cardboard at- board. The tbllowing labels are attached: / tached to a very thin, contemporary pin. Two "(elongatum) coarctatum Type from Thomson small, square labels are present: /"Sc"/"Stenb"/ Dec.br 1867" (in A. Matthews' handwriting) / (= Scania/L. Stenberg) written in ink (not Thom- "elongatum" (Thomson's handwriting) /"Mö" son). This specimen possibly also emanates (printed; = Malmö)/"Stbg" (printed; = Sten- fiom Stenberg's collecting site at Malmö. berg)/. The blue label and the mounting techni- I suspect that the Råby-pin with the missing que is typical of the British coleopterist Andrew specimen bore the (sole?) syntype of Ptilium Matthews. whose main collection of Ptiliidae is elongatum Thomson, 1855. The accurate des- preserved in London (BMNH). cription and the coffect interpretation of additio- It is known that Thomson, on a request from nal specimens indicate that Thomson's interpre- Matthews, sent some ptiliid beetles for investi- tation of the species was correct, and that the gation (cfr. Matthews 1866), among others missing specimen therefore was coffectly iden- Baeocrara littoralis (Thomson, 1855) (= B. v,r- tified.