Pantolyta simplicior, Chemyreva & Kolyada, 2021

Pantolyta simplicior sp. nov.

( Figs 4G, 7D, 10E, 12D, 14F)

Holotype. Female; Russia, Sakhalin Prov., Kunashir I., Tret’yakovo , 5.VII.1973, I. Kerzhner leg. ( ZIN).

Description. Female. Body length 2.5 mm; fore wing length 2.1 mm; antenna length 1.5 mm.

Coloration. Head, mesosoma and metasoma (except petiole) brown; antenna, mandible, venation, legs, petiole and palpi pale brown.

Head not nasiform, in dorsal view transverse, 0.77 times as long as wide, distinctly wider than mesosoma, smooth, with few scattered long setae. Temples just behind eyes parallel, broadly receding posteriorly. Occipital flange very narrow, without sculpture. Head in lateral view 1.2 times as high as long. Malar space 0.8 times as long as maximum diameter of eye. Eye pubescent. Face (including antennal shelf) smooth, with long scattered setae. Head in frontal view without mouth conus; genae weakly convex and converging toward mouthparts. Clypeus transverse, 0.67 times as high as wide. Tentorial pits large. Labrum small, semicircular, hardly discernible. Mandibles simple (Fig. 7D).

Antenna slender, weakly broadened apically ( Fig. 4G). Ratios of length to width of A1–A 15 in dorsal view: A1 (48: 8); A2 (18: 7); A3 (26: 6); A4 (18: 6); A5 (16: 6); A6 (14: 6); A7 (14: 6); A8 (13: 7); A9 (12: 7); A10 (12: 8); A11 (12: 9); A12 (11: 9); A13 (11: 9); A14 (11: 9); A15 (20: 9).

Mesosoma slightly compressed, 1.9 times as high as wide, in dorsal view 1.82 times as long as wide. Sides of pronotum smooth with few scattered long setae (setae denser on pronotal collar); epomia strongly reduced; pronotal pit bare and smooth (Fig. 10E). Mesoscutum as long as wide, convex, with few scattered semierect setae. Notauli deep and complete, not sculptured. Anterior scutellar pit deep, transverse, 0.55 times as long as wide. Scutellum large, widened posteriorly. Axillar depression weakly pubescent, with two verriculate tubercles posteriorly (Fig. 12D).

Fig. 16. Pantolyta , male. Fore tibia. A, P. sciarivora ; B, P. flaviventris .

Mesopleuron scarcely pubescent, subalar bridge posterodorsally and epicnemial bridge anteroventrally strongly reduced; epicnemial pit deep and pubescent; mesopleural pit developed as a shallow depression (Fig. 10E). Metascutellum narrow, smooth and weakly pubescent; dorsellum distinct, with three short longitudinal keels. Propodeum transverse, 0.53 times as long as wide, pubescent laterally; median propodeal keel strongly reduced; upper and lower posterior propodeal projections forming very small teeth (Fig. 12D). Sides of propodeum entirely pubescent, with one longitudinal keel. Legs slender.

Fore wing with closed radial cell (Fig. 14F); distance from marginal vein to basal vein / marginal vein length / radial cell length as 10 / 10 / 17.

Petiole of metasoma cylindrical, 1.17 times as long as wide, with weakly visible striate sculpture and few scattered setae laterally; petiole ventrally with several bunches of setae; posterior margin of petiole not arcuate (Fig. 12D). T2 anteriorly with short and hardly visible striation, median groove the longest; T3–T6 narrow, with few scattered setae laterally; T7 and T8 long, strongly compressed laterally. S2 with short grooves at base and with numerous erect scattered setae; S3–S5 narrow, with scattered setae; S6 distinctly elongate and compressed, with few scattered setae.

Male. Unknown.

Comparison. Pantolyta simplicior sp. nov. can be distinguished from all known species of Pantolyta by the combination of the following characters: the head is not nasiform and has no mouth conus (Fig. 7D); the genae are convex in frontal view; the female antenna is slender, weakly broadened apically, with A3–A7 more than twice as long as wide ( Fig. 4G); pronotal pit is bare and smooth; subalar and epicnemial bridges on mesopleuron are strongly reduced; the mesopleural pit is as a shallow depression (Fig. 10E); median propodeal keel is strongly reduced; upper and lower posterior propodeal projections form very small lateral teeth (Fig. 12D); the fore wing has a closed radial cell, marginal vein as long as the distance from marginal vein to basal vein and distinctly shorter than radial cell; the petiole is weakly elongate.

Etymology. The species name is the Latin adjective simplicior (simpler).

Distribution. Russia (Kunashir Island).

Host. Unknown.

A key to the Palaearctic species of Pantolyta and Anommatium

Note. In addition to 15 species considered in this paper, the key includes the following seven species considered in Chemyreva & Kolyada (2019): Pantolyta atrata Förster, 1861 , P. elegans Chemyreva et Kolyada, 2019 , P. hadrosoma Macek, 1993 , P. marginalis Kieffer, 1909 , P. nixoni Macek, 1993 , P. pallida Kieffer, 1908 , and P. stylata Macek, 1993 .

Females

1. Wingless or micropterous (wings reduced, with venation indistinct) (Fig. 15E)................... 2

– Alate or brachypterous (venation distinct)....... 4

2. Antenna with 13 or 14 segments; ocelli and notauli absent ( Fig. 3D); maxillary palpus one-segmented, labial palpus obliterated, represented by a small tubercle ( Fig. 3C); petiole transverse ( Fig. 3A, D)........................................ A. ashmeadi

– Antenna 15-segmented; ocelli present; notauli complete; maxillary palpus 5-segmented, labial palpus 3-segmented; petiole more or less elongate...... 3

3. Head higher than wide in frontal view and longer than wide in dorsal view; clypeus as high as wide; antenna stout, A4–A14 transverse; upper and lower posterior propodeal projections inconspicuous................................... P. atrata (partly)

– Head transverse in both frontal (Fig. 7F) and dorsal views; clypeus transverse (Fig. 7F); antenna slen- der, A4–A14 elongate ( Fig. 4H); upper and lower posterior propodeal projections large (Fig. 11G)...................................... P. macrocera

4 (1). Radial cell open............................ 5

– Radial cell closed (Fig. 14)...................... 8

5. Antennal shelf slightly prominent, head unspecialised................................. P. pallida

– Antennal shelf strongly prominent, head nasiform ... .... ... ... .... ... .... ... ... .... ... .... ... .. 6

6. Eyes small, largest diameter of eye at most 0.55 times as long as distance from eye to top of antennal shelf; A4–A8 elongate....................... P. stylata

– Eyes larger, largest diameter of eye at least 0.85 times as long as distance from eye to top of antennal shelf; A4–A8 transverse to subquadrate.............. 7

7. Temple in dorsal view parallel... P. atrata (partly)

– Temple in dorsal view receding........ P. semirufa

8 (4). Mesopleuron posterodorsally without subalar bridge; antennal shelf strongly prominent anteriorly.......................................... 9

– Mesopleuron posterodorsally with subalar bridge; antennal shelf weakly prominent anteriorly...... 11

9. Pronotal collar and dorsal posterior corner of pronotum rounded, epomia obsolete; A1 with sharply pointed flange.......................... P. nixoni

– Pronotal collar rugose, with transverse keel; dorsal posterior corner of pronotum angular; epomia present; A1 without apical flange............. 10

10. Genae in frontal view convex; upper posterior propodeal projection large............. P. hadrosoma

– Genae in frontal view strongly receding to mouthparts ( Fig. 2A); upper posterior propodeal projection small......................... P. marginalis

11 (8). Pronotal collar bare, with complete transverse keel extending from one pronotal corner to another; epomia well-developed; mouth conus slightly prominent ( Fig. 2B).......... P. elegans

– Pronotal collar pubescent, transverse keel absent or interrupted medially; epomia absent or partly developed as a short keel inside of pronotal pit (Fig. 9D); mouth conus indistinct (Fig. 7)................. 12

12. Flagellum gradually incrassate ( Fig. 4)........ 13

– Flagellum filiform ( Fig. 5)..................... 17

13. Pronotal pit with short epomia inside (Fig. 9D); radial cell at most as long as marginal vein (Fig. 14A–D); upper and lower posterior propodeal projections strong (Fig. 10B, D).......... 14

– Pronotal pit without epomia inside; radial cell distinctly longer than marginal vein (Fig. 14F); upper and lower posterior propodeal projections small (Fig. 10C)................................... 16

14. Median propodeal keel bifurcate or doubled throughout, with closely adjacent branches (if branches almost fused, then keel with groove on its top); temples behind eyes sharply receding (Fig. 8A); petiole as long as wide to slightly elongate (Fig. 11F)............ P. dichromia sp. nov.

– Median propodeal keel simple (Figs 11B and 12F); temples behind eyes broadly receding (Fig. 8B, E); petiole transverse (Figs 11B and 12F).......... 15

15. Genae strongly convex in frontal view (Fig. 7C); A15 as wide as A 14 in dorsal view ( Fig. 4F)....................................... P. nigrocincta

– Genae slightly convex in frontal view ( Fig. 2C); A15 distinctly wider than A 14 in dorsal view ( Fig. 4E).................... P. melniki sp. nov.

16 (13). Antenna stout ( Fig. 4A); temples in dorsal view and genae in frontal view strongly receding; median propodeal keel distinct (Fig. 12C).................................... P. rufiventris

– Antenna slender ( Fig. 4G); temples in dorsal view and genae in frontal view convex (Fig. 7D); median propodeal keel strongly reduced (Fig. 12D)................................... P. simplicior sp. nov.

17 (12). Median keel of propodeum bifurcate or doubled (Figs 11H and 12A, B, E)................. 18

– Median keel of propodeum simple (Fig. 11A, C–E) ... .... ... .... ... .... ... ... .... ... .... ... .... 21

18. Metasoma beyond petiole very strongly compressed laterally and strongly elongate (Fig. 15A).......................................... P. flaviventris

– Metasoma beyond petiole fusiform and at most in apical third laterally compressed............... 19

19. Pronotal pit bare, with short epomia inside (Fig. 9E); temples in dorsal view (Fig. 8D) and genae in frontal view strongly convex (Fig. 7A)........................................... P. radialis

– Pronotal pit weakly pubescent, epomia absent (Fig. 9B); temples in dorsal view (Fig. 8C) and genae in frontal view not convex (Fig. 7E)........ 20

20. Radial cell very long, at least 1.75 times as long as marginalis (Fig. 14J); median propodeal keel forked usually from base (rarely, from mid-length), this bifurcation narrow and without coarse sculpture between keels (Fig. 12E); A15 more than 1.8 times as long as A14 ( Fig. 5G).............. P. sciarivora

– Radial cell shorter, at most 1.5 times as long as marginalis (Fig. 14H); median propodeal keel widely bifurcate in posterior half, with coarse sculpture between branches of keel, or entirely between plicae (Fig. 12B); A15 less than 1.5 times as long as A14 ( Fig. 5E).................. P. pseudosciarivora

21 (17). Pronotal pit bare, with short epomia inside (Fig. 9C).................................... 22

– Pronotal pit weakly pubescent, epomia absent (Fig. 9A).................................... 23

22. Antenna stout, with flagellomeres A4–A6 at most 1.5 times as long as wide, usually more or less subquadrate ( Fig. 5C); metasoma beyond petiole elliptical with pygidium less pronounced; genae in frontal view convex (Fig. 7B); petiole elongate (Fig. 11E)........................... P. micans

– Antenna slender, with A4–A6 at least twice as long as wide ( Fig. 5H); metasoma beyond petiole elongate, fusiform, with straight and sharply pointed pygidium; genae in frontal view sharply receding to mouthparts ( Fig. 2D); petiole transverse (Fig. 11A)......................... P. seticornis

23 (21). Marginal vein longer than distance from it to basal vein (Fig. 14E); flagellum with A4 longer than wide ( Fig. 5B)................ P. flexinervis

– Marginal vein shorter than distance from it to basal vein (Fig. 14G); flagellum with A4 subquadrate ( Fig. 5D)............................. P. nitida

Males

1. Radial cell open................................ 2

– Radial cell closed............................... 6

2. Antennal shelf slightly prominent, head unspecialised (Fig. 8)................................. 3

– Antennal shelf distinctly prominent, head nasiform .............................................. 4

3. Head as long as wide in dorsal view and higher than wide in frontal view, with mouth conus ( Fig. 1A); clypeus as high as wide; A3 with distinct keel and emargination at base; dorsal posterior corner of pronotum angular.................... P. pallida

– Head transverse in frontal ( Fig. 3B) and in dorsal views ( Fig. 3H), without mouth conus; clypeus transverse ( Fig. 3B); A3 without keel, straight or with weak emargination at base; dorsal posterior corner of pronotum rounded......... A. ashmeadi

4 (2). Eye small, largest diameter of eye at most 0.7 times as long as malar space........ P. stylata

– Eye larger, largest diameter of eye at least 0.9 times as long as malar space.......................... 5

5. Temples in dorsal view parallel; fore tibia curved, with row of long stout setae; A3 thickened, deeply emarginate........................... P. atrata

– Temples in dorsal view receding; fore tibia straight, with homogeneous pubescence; A3 slender, shallowly emarginate.................... P. semirufa

6 (1). Mesopleuron posterodorsally without subalar bridge; antennal shelf strongly prominent anteriorly.......................................... 7

– Mesopleuron posterodorsally with subalar bridge; antennal shelf weakly prominent anteriorly......... 9

7. Pronotal collar smooth; dorsal posterior corner of pronotum rounded, epomia obsolete; A1 with sharply pointed flange................. P. nixoni

– Pronotal collar rugose, with transverse keel; dorsal posterior corner of pronotum angular; epomia present; A1 without apical flange................... 8

8. Genae in frontal view convex; antenna stout, A13 2.0–2.7 times as long as wide...... P. hadrosoma

– Genae in frontal view strongly receding to mouthparts; antenna slender, A13 3.3–3.7 times as long as wide............................ P. marginalis

9 (6). Pronotal collar bare, with complete transverse keel between dorsal posterior corner of pronotum; epomia well-developed; mouth conus weak but distinct ( Fig. 2B)....................... P. elegans

– Pronotal collar pubescent, with transverse keel absent or interrupted medially; epomia absent or present as a short keel inside of pronotal pit (Fig. 9D); mouth conus indistinct ( Fig. 2C, D and 7)...... 10

10. Pronotal pit bare, with short epomia inside (Fig. 9C–F)................................. 11

– Pronotal pit weakly pubescent, epomia completely absent (Fig. 9A, B)........................... 17

11. A3 with deep emargination overreaching mid-length of segment ( Fig. 6D).... P. melniki sp. nov.

– A3 with weaker emargination, which usually not overreaching mid-length of segment ( Fig. 6C, F, I, K, L)........................................ 12

12. Median propodeal keel bifurcate or doubled (Fig. 13H, J)............................... 13

– Median propodeal keel simple (Fig. 13B, C, G)..... ........................................... 14

13. Genae in frontal view and temples in dorsal view distinctly convex (Fig. 7A); median propodeal keel widely bifurcate at about mid-length, with coarse sculpture between branches of keel (Fig. 12A).................................. P. radialis (partly)

– Genae in frontal view and temples in dorsal view sharply receding to mouthparts ( Fig. 1B); median propodeal keel forked from base, this bifurcation narrow and without coarse sculpture between branches of keel (Fig. 11F)............................................... P. dichromia sp. nov.

14 (12). Genae in frontal view convex (as in Fig. 7B, C) ............................................. 15

– Genae in frontal view not convex, sharply receding to mouth parts (as in Figs 2D and 7F).......... 16

15. Upper and lower posterior propodeal projections large (as in Figs 10B and 13C); volsellae and dents in genitalia fused................. P. nigrocincta

– Upper and lower posterior propodeal projections small (Figs 10A and 13B); volsellae and dents separated........................... P. micans

16 (14). Pubescence of A3–A15 long, more than half as long as width of segment, semierect (Fig. 15F); petiole more than twice as long as wide........................................... P. macrocera

– Pubescence of A3–A15 shorter, at most as long as half of width of segment, recumbent ( Fig. 6L); petiole at most twice as long as wide (Fig. 13G)...................................... P. seticornis

17 (10). A3 straight, not emarginated at base ( Fig. 6J)........................... P. pseudosciarivora

– A3 emarginated at base ( Fig. 6A, B, E, F, G, H)..... ... .... ... ... .... ... .... ... ... .... ... .... .... 18

18. Genae in frontal view distinctly convex (as in Fig. 7A)..................................... 19

– Genae in frontal view sharply receding to mouthparts (Fig. 7E)............................... 21

19. Radial cell as long as marginal vein or slightly longer (Fig. 14I); pronotal pit bare (Fig. 9E, F)................................. P. radialis (partly)

– Radial cell about twice as long as marginal vein (Fig. 14G); pronotal pit weakly pubescent....... 20

20. Antenna slender, A4–A14 about five times as long as wide (Fig. 15B); median propodeal keel bifurcate posteriorly; metasoma slightly compressed (Fig. 15C)............... P. flaviventris (partly)

– Antenna stout, A4–A14 twice as long as wide or shorter ( Fig. 6B); median propodeal keel simple (Fig. 13D); metasoma depressed........ P. nitida

21 (18). Metasoma beyond petiole narrow, slightly compressed (Fig. 15C); fore tibia widened interiorly, with somewhat stouter bristles (Fig. 16B)................................ P. flaviventris (partly)

– Metasoma beyond petiole wide and slightly depressed (Fig. 15D); fore tibia simple, with weaker, unspecialised pubescence (Fig. 16A)........... 22

22. Occiput behind ocelli with dense pubescence........................................ P. rufiventris

– Occiput behind ocelli with sparse pubescence (Fig. 8C).................................... 23

23. Petiole stout, less than 1.5 times as long as wide (Fig. 13A); marginal vein distinctly longer than distance from it to basalis (Fig. 14E)... P. flexinervis

– Petiole more elongate, about twice as long as wide (Fig. 15D); marginal vein shorter (occasionally slightly longer) than distance from it to basalis (Fig. 14J)......................... P. sciarivora