Baetis jaervii sp. n. (Ephemeroptera: Baetidae) from northern Europe

Baetis jaervii sp. n. is described and illustrated. The history and relationships of this taxon to related species are elucidated on the basis of literature and determinations of genetic distance and mtDNA barcodes. B. jaervii is the only representative of the B. vernus group found in northern Europe, the nymphs of which live in lakes. The population from northern Finland earlier assigned to Baetis tracheatus should be transferred to represent B. jaervii

The Baetis vernus group (Ephemeroptera: Baetidae) of northernmost Europe: an evidently diverse but poorly understood group of mayflies

The Baetis vernus group is known to be a taxonomically difficult group of mayflies. Morphological characters such as themandibles or gills of nymphs overlap widely. We report here that enzyme electromorph frequencies also fail to show reproductive isolation in many cases. Baetis macani has been divided in the literature into two forms, a lentic one with broader gills living in stagnant waters, while the lotic one with narrower gills lives in flowing water. We show that the two evidently represent reproductively isolated taxa, B. macani Kimmins = B. bundyae auct. nec, while the one with broader gills appears to be a new species. Baetis macani, B. subalpinus, B. liebenauae and B. vernus form a cluster that is genetically not divisible according to the recognized species boundaries.Nymph gill length differentiates, however, B. macani from B. subalpinus and B. vernus. We call for studies on population structuring andmolecular taxonomy to resolve the taxonomy and ecology of this important group of mayflies

The genus Metretopus (Ephemeroptera, Siphlonuridae) in Fennoscandia - identification, faunistics and natural history

Morphological characters are presented for the separation of nymphs and winged stages of Metretopus alter Bengtsson, 1930, from those of M. borealis (Eaton, 1871) based on Fennoscandian material. The known records of both species in Finland and Sweden are mapped, and a recent record of M. alter from Norway is given. Habitat preferences and phenological data of both species are presented. The documented wide distribution of M. alter in Fennoscandia indicates that it previously has been confused with M. borealis

Karkali naturpark

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New records of Paraleptophlebia werneri Ulmer, 1920 and P. strandii (Eaton, 1901) from Finland (Ephemeroptera, Leptophlebiidae)

The mayfly species Paraleptophlebia werneri has been rediscovered from Finland. The species was classified as RE (regionally extinct) in the most recent national red-list assessment. The new locality is close to the Russian border in NE Lapland, Savukoski. Adult males were collected with a sweep net around a pond. Paraleptophlebia strandii is a rather poorly known but widespread Finnish species. The adults of this species occurred in great numbers in aapamires of central Lapland (Sodankylä). We hypothesize that these leptophlebid species are not dependent on running water but may instead thrive in small lentic water bodies

Käytännön lammastalous

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