Euseius finlandicus
Creators: name: Kolodochka, L. A.
Publisher: name: Zenodo
Year: 2023
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Mesostigmata
Phytoseiidae
Euseius
Euseius finlandicus

description: Euseius finlandicus (Oudemans, 1915) (fig. 9)*   
 Seiulus finlandicus Oudemans, 1915: 183.   
 Typhlodromus pruni Oudemans, 1929: 32.   
 Typhlodromus finlandicus: Nesbitt, 1951: 25.   
 Amblyseius finlandicus: Livschitz & Kuznetzov, 1972: 22; Kolodochka, 1978: 20.   
 Amblyseius (Euseius) finlandicus: Arutunjan, 1977: 39.   
 Euseius finlandicus: Hajizadeh et al., 2002: 374; Kolodochka, 2006: 98; Papadoulis et al., 2009: 31.   
 Material. Types. Holotype}, Finland, Turun Porin Laani, Åbo, on Prunus domestica, Euseius pruni (Oudemans, 1929): 32; (Junior synonym of Seius finlandicus Oudemans, 1915: 183). This species is represented by three preparations, nos. 377 (figs 117–119 in the Archive für Naturges), 378 and 379 kept in the Oudemans collection at the Leiden Museum, Finland, Åbo, on Salix caprea ” (Nesbitt, 1951: 25) (not examined) (RMNH).   
 Non-type. 6725 specimens ( 5574}, 1151 {) — throughout Ukraine.   
 R e d e s c r i p t i o n. F e m a l e. Dorsal shield (fig. 9, 1) weakly sclerotised, oval, with pronounced lateral emarginations and indistinct reticulate sculpture; 6 pairs of solenostomes (iv, id, isc, il, is, ic; it missing). Setae of dorsal shield short, except for elongated and weakly serrated PM 4. Peritremes short, barely extending beyond the thecae of setae AL 2. Ventrianal shield (fig. 9, 2) elongated, with distinct lateral emarginations; anal pores rounded, distinct, not close together. One pair of metapodal scutes (anterior scutes are reduced). They are elongated, caudally pointed (fig. 9, 3). The peritreme shield consists of three fused cuticle lobes of varying degrees of sclerotization, the boundaries between which are indicated by sculpture lines. The posterior end of the shield widens caudally and bears a round pore (fig. 9, 4). Df chelicera with 6 small teeth, Dm with 1 tooth (fig. 9, 5). Spermatheca with short neck and small funnel (fig. 9, 6). Leg IV has 3 pointed macrochaetes; approximately equal in length on tibia and stifle, distinctly longer on basitarsus, often characteristically curved at end (fig. 9, 7).   
Measurements. Lds 330, Wds 195; Lvas 98, Wvas 65, Lian 23; Lt 123; setae length: AD 1 28; AD 2 15; AD 3 15; AD 4 17; PD 1 17; PD 4 6; AM 1 32; AM 2 14; AL 1 27; AL 3 27; AL 4 36; PL 1 21; PL 2 22; PL 3 23; PM 1 17; PM 3 19; PM 4 45; AS 18; PS 17; PV 31; MCh IV: ti, 33, ge 31, ta 54.  
 Male. Ventrianal shield (fig. 9, 8) with 3 pairs of preanal setae; anal pores rounded. Spermatodactyl smoothly curved, tapering towards the end (fig. 9, 9). Lds 250.   
 Diagnosis. With signs of the genus. For information about the differences between E. finlandicus and closely related E. ucrainicus Kolodochka, see the species profile of the latter.   
 D i s t r i b u t i o n, h a b i t a t, o c c u r r e n c e. Known in the fauna of both hemispheres and is often the most common species of the family on deciduous trees and shrubs, to which it gives a clear advantage, although it is also found on grasses. It can be found on conifers too, but such a find is always accidental. According to our data, E. finlandicus inhabits more than 70 plant species in Ukraine. It is common in natural and cultivated cenoses, — parks and green spaces along roads and city streets, plantings of summer cottages and household plots, abandoned gardens. Often dominates in phytoseiid complexes; mass.   
Note. Description, morphometry, and illustrations are based on specimens from env. Kyiv after comparing them with illustrations of this species in the publications of various authors.
description: Published as part of Kolodochka, L. A., 2023, The Predatory Mites (Phytoseiidae, Parasitiformes) In The Fauna Of Ukraine: Genera Paragigagnatus, Carinoseius, Kampimodromus, Eharius, Typhlodromips, And Euseius, pp. 477-506 in Zoodiversity 57 (6) on page 501, DOI: 10.15407/zoo2023.06.477, http://zenodo.org/record/10788561