Homalotylus tianjinensis Zu, 2023

Zu, Guohao, Xue, Hao, Wang, Haiyang, Zhen, Wenquan & Huang, Dawei, 2023, Description of three new species and new distributional data for three species of Homalotylus (Hymenoptera, Encyrtidae) from China, ZooKeys 1184, pp. 273-289 : 273

Homalotylus tianjinensis Zu sp. nov.

Figs 19-25

Type materials.

Holotype. ♀ [on slide], China, Tianjin City, Xiqing District, Tianjin Agricultural University, 39°5'21"N, 117°5'38"E, c. 13 m, 18.VI-3.VII.2019, Guo-Hao Zu, Ze-Ning Yang, Malaise trapping. Paratypes. ♀ [on slide], China, Tianjin City, Xiqing District, Tianjin Agricultural University, 39°5'21"N, 117°5'38"E, c. 13 m, 30.V-14.VI.2020, Ze-Ning Yang, Chen Zhang, Malaise trapping.

Description.

Female. Holotype. Length, excluding ovipositor, 2.20 mm. Face yellowish brown, frontovertex dark brown, genae dark brown. Antennae dark brown, F6 from brown to white, clava white. Mesosoma black brown, but axilla yellowish brown, scutellum yellowish with a diamond-shaped brown area at the base; tegula white; wings largely hyaline but fore wing infuscate at base and with a distinct, broad more or less parallel-sided brown fascia across immediately distad of this, otherwise apical setae normal and dark; legs dark brown, except for apical 1/5 of mid tibia, all tibial spurs, mid and hind tarsus 1-4 white. Metasoma black, the protruding part of the ovipositor black brown, with only the base yellowish white.

Head (Fig. 19 ) with numerous conspicuous setae on frontovertex, each about as long as diameter of posterior ocellus; piliferous punctures shallow. Head in front view about 1.13 × higher than wide. Frontovertex about 1/6 head width, and narrowest about midway between posterior ocelli and occipital margin, eye margins conspicuously diverging anteriorly. Ocelli forming an angle of about 40°. Malar space 0.17 × eye height. Antennal torulus with its dorsal margin below lower eye margin and very close to oral margin. Clypeal margin slightly convex. Antennal (Fig. 20 ) scape slender, almost 7.60 × as long as wide; pedicel 2.5 × as long as wide, 1.49 × as long as F1; all funicle segments longer than wide, F1 1.74 × as long as wide, F6 1.26 × as long as wide; funicle with linear sensilla on all segments; clava 3-segmented, about as long as F4-F6 combined, apex strongly obliquely truncate, truncate part approach to the middle of the first clava segment. Measurements (μm): HH, 590; HW, 530; FV, 90; EL, 500; MS, 87; OD, 38; POL, 38; OCL, 76; AOL, 66; length and (width)-radicle, 125; scape, 380 (50); pedicel, 130 (52); F1, 87 (50); F2, 85 (57); F3, 80 (60); F4, 82 (62); F5, 80 (62); F6, 82 (65); clava, 232 (65).

Mesosoma (Fig. 21 ) with sculpture on mesoscutum of similar mesh size to that on frontovertex, but much shallower; sculpture on scutellum similar to that on frontovertex, but slightly deeper and coarser; notaular lines conspicuous but not quite meeting at middle of posterior margin of mesoscutum. Scutellum about as long as wide and about as long as mesoscutum. Fore wing (Fig. 22 ) 2.78 × as long as width; venation and setation as in Fig. 23 ; costal cell narrow; linea calva interrupted by 3 lines of setae and closed posteriorly by 5 lines of setae; marginal vein about 1.5 × as long as wide; postmarginal vein slightly shorter than stigmal vein, angle between them about 30°. Hind wing (Fig. 23 ) 3.81 × as long as width. Length of mid tibial spur (Fig. 25 ) about 0.45 × of mid tibia and longer than mid basitarsus. Measurements (μm): FWL, 1420; FWW, 510; SMV, 645; MV, 62; PMV, 145; SV, 151; HWL, 1030; HWW, 270; MT, 860; mid tibial spur, 390; mid basitarsus, 350.

Ovipositor (Fig. 24 ) distinctly exserted, 1.14 × as long as mid tibia and the exserted part nearly equal to mid tibial spur. Measurements (μm): OL, 980.

Male. Unknown.

Host.

Unknown.

Etymology.

The specific name refers to its collecting location.

Diagnosis.

The new species may be distinguished from H. albiclavatus (Agarwal, 1970) and H. vicinus Silvestri, 1915, by the following characters: scape completely dark brown, 7.60 × as long as wide (with a long light-colored strip medially, 8.55 × in H. albiclavatus ), F6 from brown to white (completely white in H. albiclavatus ), scutellum yellowish with a diamond-shaped brown area at the base (yellow in H. albiclavatus ); F6 from brown to white (dark in H. vicinus ), hind femur dark brown (ventrally pale yellow apically in H. vicinus ), hind tarsus 1-4 white (2-4 white in H. vicinus ).

Figures

Figures 19 - 25. Homalotylus tianjinensis Zu, sp. nov., holotype, female 19 head 20 antenna 21 mesosoma 22 fore wing 23 hind wing 24 metasoma 25 legs. Scale bars: 100 μm.