A new species of Psyllaephagus (Hymenoptera: Encyrtidae) from China, parasitoid of Macrohomotoma sinica (Hemiptera: Homotomidae) on Ficus concinna

Abstract Background During the investigation of forest insects in Guilin, Guangxi, encyrtid parasitoid wasps belonging to the genus Psyllaephagus were reared from Macrohomotoma sinica (Hemiptera: Homotomidae) feeding on Ficus concinna. New information A new species of Psyllaephagus Howard (Hymenoptera: Encyrtidae), P. guangxiensis Zu sp. nov., is described from Guangxi, China as a parasitoid of Macrohomotoma sinica Yang & Li (Hemiptera: Homotomidae) on Ficus concinna (Miq.) Miq. (Urticales: Moraceae).


Materials and methods
Specimens of the host Homotomidae were collected from F. concinna in Guilin City, Xiangshan District, Wanshou Lane and Xicheng Road on 8 August 2018 and 14 July 2020, respectively, then reared in nylon net bags (150 mesh size). When the parasitoid wasps appeared, they were collected and preserved in 99% ethanol. The four reared specimens (2♀♀, 2♂♂) were dissected and mounted on slides according to Noyes (1982). Body lengths were measured with a Leica M205A stereomicroscope, other measurements being taken using a Olympus CX21 optical microscope equipped with a micrometer in the eyepiece. Morphological terminology and abbreviations follow Noyes (2010).
The holotype of the new species is deposited in the 'insect collections' of Tianjin Agricultural University (TJAU), China.

Taxon treatment
Psyllaephagus guangxiensis Zu, sp. n. Frontovertex (Fig. 1A) 0.28× head width, with distinct piliferous punctures of a thimblelike appearance, sculpture reticulate, more longitudinally elongate on lower parts of face and on genae; ocelli forming an angle of 73°; posterior ocellus closer to eye margin than to occipital margin; antennal torulus with its dorsal margin well above lower margin of eyes. Antennal scape (Fig. 1B)  Mesosoma (Fig. 1C). Mesoscutum and scutellum with fine reticulate sculpture; scutellum 1.07× as long as wide and 0.88× as long as mesoscutum. Fore wing (Fig.  1D) 2.28× as long as wide; linea calva closed by one line of setae posteriorly, uninterrupted; postmarginal vein about as long as stigma vein; hind wing ( Fig. 1E) 3.55× as long as broad. Mid-tibial spur (Fig. 1F) 0.25× as long as mid-tibia and shorter than corresponding basitarsus. Measurements (μm): fore wing length, 1425; fore wing  Male. Length 0.95-1.38 mm. Generally very similar to female in appearance except for colouration of frontovertex, mesoscutum and scutellum with copper green reflection, relatively less dense setae in basal cell of fore wing and structure of antennae and genitalia. Head, in frontal view ( Fig. 2A), (1.23×) wider than high; frontovertex 0.53× head width, with distinct piliferous punctures of a thimble-like appearance, sculpture polygonal; ocelli forming an angle of 130°; antennal torulus with its dorsal margin well above lower margin of eyes. Antennal scape (Fig. 2B) broadened, about 2.5× as long as broad; all funicle segments subquadrate or slightly longer than wide. Fore wing (Fig.  2D) about 2.17× as long as wide; hind wing ( Fig. 2E) 3.30× as long as wide. Mid-tibial spur (Fig. 2F) 0.22× as long as mid-tibia and shorter than corresponding basitarsus. Metasoma (Fig. 2C) shorter than mesosoma; aedeagus about 1.52× as long as midtibia.
Variation. Very little morphological variation has been found in material included in the type series.

Diagnosis
Female. Length, 2.02-2.50 mm. Body stout, dark brown, head, mesoscutum, scutellum and axilla with bright green metallic reflection; tegulae white; legs pale yellow, except hind coxa partly brown; frontovertex slightly more than a quarter of head width, with distinct piliferous punctures of a thimble-like appearance; ocelli forming an acute triangle; scape broadened, about 2.7× as long as broad; F1 shorter than pedicel; fore wing hyaline, about 2.3× as long as wide; ovipositor distinctly exserted, 2.14× as long as mid-tibia.

Etymology
The specific name refers to the collecting location of the type series. Noun in apposition.

Taxon discussion
According to the keys in Tang