Amblyseius wainsteini Gomelauri, 1968

Amblyseius wainsteini Gomelauri, 1968 ( fig. 15 View Fig )

Amblyseius wainsteini Gomelauri, 1968 a: 518 .

Amblyseius (Amblyseius) wainsteini : Wainstein & Vartapetov, 1973: 103.

Amblyseius wainsteini : Karg, 1993, 181.

Amblyseius similis : Kolodochka, 2006: 229; Kolodochka & Omeri, 2011: 33;

Transeius wainsteini : Demite at al., 2024 ( Phytoseiidae Database View in CoL ).

Zercon similis Koch, 1839 = Typhlodromus similis Koch, 1839: 27 — nomen dubium: Chant & McMutrtry, 2004.

Material. Types. Syntypes 7 ♀, Georgia, Manglisi [town], on Corylus , July 1956 (No. of the specimen unknown) ( IZGT) .

Non-type. 500 ♀, 108 ♂ (608 specimens) — Lviv, Rivne, Ternopil Regions .

R e d e s c r i p t i o n. F e m a l e. The dorsal shield (fig. 16, 1) is moderately sclerotised, elongated-oval, expanded caudally, smooth except lateral striations, relatively well-defined solenostomes 7 pairs (it, iv, id, isc, il, is, ic). Setae AM1, AL4, PM3, and PM4 are significantly longer than the other dorsal setae. The setae PM3 and PM4 are serrated, the rest are smooth. Seta AM1 extends far beyond the theca of seta AL1. Seta AL1 is insignificantly shorter or almost equal to the distance to theca AL3. Seta AL3 longer than AL1. Seta PL1 is 2 times longer than PL2 and 3 times longer than PL3. Peritremes long, reaching the bases of setae AD1. Setae St3 sit on small posterolateral processes of the sternal shield, between which the posterior edge of the shield is straight ( fig. 15 View Fig , 2 View Fig ). MSt setae located on scutes. The ventrianal shield is almost equal in width to the genital shield, elongated, has lateral notches and sculpture in the form of thin transverse lines; often variable in form; anal pores close together, semilunar. Metapodal scutes are narrow, the anterior one is smaller than the posterior one ( fig. 15 View Fig , 3 View Fig ). The posterior part of the peritremal shield is slightly curved, beak-shaped at the end, with a pore ( fig. 15 View Fig , 4 View Fig ). There are 9 chelicerae on Df and 2 on Dm ( fig. 15 View Fig , 5 View Fig ). The spermatheca is small, the funnel is cup-shaped, the atrium is sessile ( fig. 15 View Fig , 6 View Fig ). Leg IV has 3 macrochaetae; longest on the tarsus, slightly shorter on the genu ( fig. 15 View Fig , 7 View Fig ), shortest on the tibia; genua III–I have one by one short macrochaeta.

M e a s u r e m e n t s: Lds 375, Wds 210, Lvas 127, Wvas 93, Lian 22, Ltar IV 140; setae length: AD1 28; AD2 10; AD3 9; AD4 11; PD2 11; PD4 11; AM1 55; AM2 8; AL1 23; AL3 32; AL4 73; PL1 33; PL2 17; PL3 10; PM1 13; PM3 67; PM4 134; AS 29; PS 20; РV 78; MCh IV: ge 62, ti 53, ta 70; MCh III: ge 25; MCh II: ge 24; MCh I: ge 22.

Male. Preanal setae 3 pairs; anal pores are large, semilunar (fg. 15, 8). Spermatodactyl with a coracoid process directed forward and upwards ( fig. 15 View Fig , 9 View Fig ). Lds — 277.

D i f f e r e n t i a l d i a g n o s i s. Amblyseius wainsteini is very similar to A. andersoni . The most reliable sign of the difference between females of these species is the structure of the spermatheca. The atrium in A. andersoni is connected to the infundibulum by a short neck, while in A. wainsteini the atrium is sessile and does not have a neck. Males differ in the structure of the spermatodactyl ( fig. 1 View Fig , 9 View Fig ; fig. 15 View Fig , 9 View Fig ). These signs are not always in a position convenient for research when the mite is attached to a glass slide. At the same time, the use of the dorsal chaetom provides clear differences between these species in the length of the dorsal setae AD2 7; AM1 39; AL1 14; AL3 22 (in A. andersoni ) and, accordingly, AD2 10; AM1 55; AL1 23; AL3 32 (in A. wainsteini ). This difference is persistent and, according to our data, serves as a reliable basis for separating these species when serially identifying specimens. An even simpler way to distinguish these species is to use the ratio of the length of the AL1 setae to the distance between the AL1 and AL3B setal thecae (Kolodochka and Omeri, 2011: 33–36). The AL1 seta in A. wainsteini is almost equal to or slightly shorter than this distance (the differences are not significant at a significance level of less than 1 %), whereas in A. andersoni the length of the AL1 seta does not exceed half the length of the AL1 seta. A sign that is convenient at first glance – the difference in the number of teeth on Dm – is not always a sign that one should rely on, since (Attention!) in A. andersoni the middle tooth on one from any Dm may be absent.

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. Europe ( Germany, Denmark, Slovakia), Southern Caucasus ( Georgia), Northern Caucasus (Karachayevo-Cherkessia), Western Asia ( Iran, Turkey). In Ukraine: only a few local habitats of A. wainsteini are known in three western regions, where it is found on trees and shrubs, occasionally on perennial grasses. Under natural conditions, it can sometimes form mixed populations with the widespread A. andersoni . Such cases occur in 10 % of the total number of samples containing these species together or separately. In cultural phytocenoses of the Wood-and-Steppe zone of Ukraine, A. andersoni is common, and A. wainsteini occurs sporadically. The possibility of the presence of hybrid individuals in the territory of coexistence of these species was checked by us and not confirmed at the morphological level. Unilateral reduction of the middle tooth on the Dm chelicerae in A. andersoni could be taken as a sign of hybridization, but such individuals are very rare and can be found in places far from the natural range of A. wainsteini . In addition, differences in the morphology of these two species simultaneously in several stable characters confirm their independence and indicate a possible relationship.

Note. Description, morphometry and illustrations were prepared using material from Rivne Region.

A key to species of the genus Amblyseius of Ukrainian fauna (females)

1 (24). Pair of setae V2 is present on the membrane near the ventrianal shield....................................................24

2 (7). Dorsal shield partially or completely covered with fine reticulate sculpture ................. …………………7

3 (4). Seta AM1 shorter than distance to theca of seta AL1............................................................... A. rademaheri

4 (3). Seta AM1 more longer than distance to theca of seta AL1 ............................................................................ 5

5 (6). Length of seta AL1 almost equal to or slightly shorter than distance to theca AL3; atrium of spermatheca sessile................................................................................................................................................. A. wainsteini

6 (5). Length of seta AL1 does not exceed half the distance to theca; atrium of spermatheca on short neck ................................................................................................................................................... A. andersoni

7 (2). Dorsal shield smooth ..........................................................................................................................................7

8 (9). Dorsal setae AL1 are shorter than AL3..............................................................................................................8

9 (10). Seta AL1 shorter than distance to theca AL3; the posterior half of the ventrianal shield is wider than the anterior half.............................................................................................................................................. A. filixis

10 (9). Seta AL1 is the same length or slightly longer than the distance to the theca AL3; the anterior half of the ventrianal shield is wider than the posterior half.................................................................... A. nemorivagus

11 (12). Dorsal setae AL1 and AL3 are of equal length ..............................................................................................11

12 (11). Funnel of spermatheca is saucer-shaped, its diameter is 1.5 times smaller than the length of the thin and “corrugated” neck......................................................................................................................... A. obtusus

13 (14). Funnel of spermatheca another shape and structure.....................................................................................13

14 (13). Funnel of spermatheca thin-walled; atrium located asymmetrically on the funnel .................................14

15 (16). Ventrianal shield pentagonal with straight lateral edges....................................................... A. neobernhardi

16 (15). Ventrianal shield pear-shaped, narrowed caudally .......................................................................... A. terreus

17 (18). Seta PM4 is club-shaped at the end .................................................................................................................17

18 (17). Funnel of spermatheca is large; the anal pores are closely related to the thecae of setae PrA2 ........... A. irinae

19 (20). Funnel of spermatheca is of medium size, narrow, finger-shaped, its outer walls are covered with very small tubercles; the anal pores are not closely related to the thecae of setae PrA2......... A. microorientalis

20 (21). Seta PM4 is pointed............................................................................................................................................21

21 (22). Funnel of spermatheca is warty, tubular, thick-walled in the middle part, widens from one end to the sessile atrium, from the other end to the sacculus ........................................................................... A. sparsus

22 (23). Funnel of spermatheca is smooth-walled, long, with walls moderately thickened up to the middle of its length, swollen at the atrium, then smoothly widening towards the sacculus ...................... A. omaloensis

23 (24). Df with no more than 4 teeth, Dm with 0–2 ....................................................................................................4

24 (25). Df with 4 teeth (large medial tooth masked by base of pilus dentilis), Dm with 2 teeth; length of spermatheca funnel 30 µm (excluding atrium) ..................................................................................... A. meridionalis

25 (24). Df with 3 teeth, Dm without teeth; length of spermatheca funnel 40 µm (excluding atrium) .................. ......................................................................................................................................................... A. kalandadzei

26 (1). Pair of V2 setae in ventrianal shield absent ....................................................................................... A. krantzi

Acknowledgements

This study was funded by the National Academy of Sciences of Ukraine for the I. I. Schmalhausen Institute of Zoology of the National Academy of Sciences of Ukraine (state registration number of the work: 0116U003015, II-51-21).