Two new species of the family Megalyridae (Hymenoptera) from China

Abstract Two new species of the small and rarely collected family Megalyridae are described from China: Carminator daliensis Chen & Liuhe, sp. nov. from Yunnan and Ettchellsia hainanensis Chen & Liuhe, sp. nov. from Hainan. A key to megalyrid species of China is provided. The biogeographical implication of the new taxa is discussed.


Introduction
Megalyridae is a small family of parasitic wasps, which, as far as known, parasitize the larvae of wood-boring beetles (Coleoptera) and more rarely mud-nesting Sphecidae (Hymenoptera) (Shaw 1990a;Naumann 1987). So far, only 62 species have been described worldwide (Binoy et al. 2020;Mita and Shaw 2020). Although rarely collected, these wasps have nevertheless been reported from most of the major biogeographic regions worldwide, with the exception of the Nearctic (Vilhelmsen et al. 2010). Most megalyrid species occur in the tropics and subtropics of the Southern Hemisphere (Vilhelmsen et al. 2010;Binoy et al. 2020). While most Asian species of megalyrids have highly restricted distribution ranges (Mita and Konishi 2011), there is one notable exception, Megalyra fasciipennis Westwood, which occurs widely in Australia and Tasmania and has been reported as accidentally introduced into South Africa and India (Binoy et al. 2020). The biogeography of megalyrids has attracted increasing attention in recent years (Shaw 1990b;Vilhelmsen et al. 2010;Mita and Konishi 2011). Therefore, an intensive field survey of megalyrids is of interest towards better understanding the diversity and distributional patterns of these wasps. Previously, Carminator cavus Shaw from Taiwan and Ettchellsia sinica He from Yunnan were the only two megalyrids described from China (Shaw 1988;He 1991). In this study, we describe two additional new species of Megalyridae from southern China.

Materials and methods
All specimens are deposited in the collections of the Museum of Biology, Sun Yat-sen University, Guangzhou, China (SYSBM). The morphological terms generally follow that of Shaw (1988Shaw ( , 1990b, and the nomenclature of the sculpture and texture of the integument follows Harris (1979). Images and measurements were made using a Nikon SMZ25 microscope with a Nikon DS-Ri 2 digital camera system. Images were post-processed with Abobe Photoshop CS6 Extended.
The following abbreviations are used: A1-A14 antennomere 1 to 14; OOL shortest distance from the outer edge of a lateral ocellus to the compound eye; LOL shortest distance between the inner edges of the lateral ocellus and the median ocellus; POL distance between the inner edges of the lateral ocelli.  Shaw, 1988.

Diagnosis.
Carminator is diagnosed by the following morphological characters: shallow subantennal groove, mandible stout and with five teeth, head prognathous, wing venation reduced and pterostigma absent, fore tibia with a comb of stout spines, ovipositor strongly arched (Shaw 1990b).

Biology.
Little is known about the biology of Carminator, but these wasps have been suspected to be parasitoids of wood-boring larvae of Coleoptera (Mita and Konishi 2011).
Distribution. Oriental, Australasian, and eastern Palaearctic regions.  1E); fore tibia with two rows of stout spines (nine + seven) arranged in a V shape (Fig. 2E); branching point between R1 and 2r of forewing not thickened (Fig. 2D). Description. Female (holotype). Body length 4.4 mm. Color. Body black; mandible reddish black; pedicel and first four flagellomeres dark brown, remainders of antenna black; legs black with tibiae dark brown to black and tarsus brown; wings tinged with brown and forewing veins dark brown; ovipositor sheath brown; ovipositor reddish brown.
Variation. The body length of the paratype female is 4.2 mm, and other characters are similar to the holotype.
Male. Unknown. Etymology. The specific epithet refers to the locality (Dali) where the type specimens were collected. It should be treated as a noun in apposition.

Diagnosis.
Posterior ocular orbits with groove and carina present; posterior border of mesopleuron smooth, without a row of foveae; propodeum with unique pattern of longitudinal carinae; forewing fuscous or with fuscous banding pattern; forewing with vein Rs between Rs + M and r-rs tubular for at least a short distance, apical segment of Rs tubular, arched towards stigma, M+ Cu and distal segments of Cu absent or at most spectral; Hind tibia rugose and with erect setae. Additional diagnostic characters for the genus were provided by Shaw (1990b), Vilhelmsen et al. (2010), and Mita and Shaw (2012).

Biology.
No biological data for Ettchellsia species are available; however, these wasps have long been suspected to be idiobiont ectoparasitoids that attack beetle larvae (Shaw 1990b Diagnosis. Frons irregularly rugose (Fig. 3C); clypeus largely punctate rugose (Fig. 3C); vertex posterior to lateral ocellus smooth anteriorly and reticulate-rugose posteriorly (Fig. 3D); gena smooth (Fig. 3E); metanotum puncate and setose medially (Fig. 4A); median propodeal region not narrowed (Fig. 4A); metasoma (Fig. 4C) smooth except tergite 6 largely coriaceous. Description. Female (holotype). Body length 4.9 mm. Color. Head black, mesosoma largely black except mesoscutum and axill reddish brown and tegula brown, metasoma mainly black with posterior margin of terga dark brown; mandible dark brown with teeth darker; antenna brown to dark brown with apical flagellomeres paler; trochanters and tarsi of fore and mid legs pale yellow, remainders of the legs brown to dark brown; trochanter and tarsus of hind leg brown, femur dark brown to black, coxa and tibia black; dorsal surface of hind tibia with both white and black long setae; basitarsus with white long setae; forewing with four transverse dark brown bands; ovipositor sheath black; ovipositor reddish brown.
Head (Fig. 3C-E) 1.5× wider than long in dorsal view, covered with long black erect setae and relatively short decumbent white setae; frons irregularly rugose; vertex convex, with ocellar triangle smooth, except by a median row of longitudinal punctures, area between ocelli and eyes smooth with a row of longitudinal punctures arising from lateral ocellus and parallel to orbit; vertex posterior to lateral ocellus smooth anteriorly and reticulate-rugose posteriorly; POL = 4.7; OL = 3.4; OOL = 4.0; eye margined posteriorly by a groove and a single postocular oribital carina, the groove smooth anteriorly and foveate posteriorly; gena smooth; occipital carina foveate; clypeus largely punctate rugose, apical margin slightly incise medially; mandible with 3 teeth; antenna filiform, A3-A6 th flagellomeres subequal and the longest, remainder flagellomeres becoming shorter. Mesosoma (Fig. 4A, B) covered with short decumbent white setae; scattered, long, erect, black setae present on mesonotum; mesoscutum humped, anterior surface smooth, dorsal surface largely smooth with fine punctures, median mesoscutal sulcus present and foveate, lateral carina of anterior surface present; axilla and mesoscutellum largely smooth with fine punctures; metanotum puncate and setose medially; propodeum with pairs of median, submedian, and lateral longitudinal carinae; median propodeal region not narrowed, with four complete and two incomplete transverse carinae, posterior margin producing dorsally; submedian region with two complete transverse carinae; lateral region with four complete transverse carinae.
Legs (Figs 3B,4E). Hind femur punctate and rugose medially; hind tibia longitudinally rugose; hind tibia covered with both white and black long erect setae, longer than the width of the hind tibia; basitarsus covered with white long erect setae, longer than the width of the hind tibia.

Metasoma
Variation. The body length of the paratype female 5.0 mm; antenna dark brown to black; mesoscutellum reddish brown; median propodeal region with seven complete transverse carinae; other characters similar to the holotype.
Male. Unknown. Etymology. The specific epithet refers to Hainan Island, where the type locality is located. It is treated as a noun in apposition.    3C); clypeus largely punctate rugose (Fig. 3C); POL distinctly longer than OL (Fig.  3D); metasomal tergite 5 smooth (Fig. 4C). We contacted the curators of the Hymenoptera collection of Zhejiang University (previously known as Zhejiang Agricultural University) where the holotype of E. sinica claimed to be deposited, but they failed to find the type. If the holotype were confirmed to be lost, a neotype of the species may need to be designated based on a specimen collected from the type locality in the future. Mita and Shaw (2012) have suggested that species diversity of megalyrids from the Southeast Asia is still undersampled and intensive study is required. Additional discoveries from this region would help us better understand the biogeography and eveolutionary history of Megalyridae.

Dicussion
Species of Carminator mainly occur in Southeast Asia. Morphologically, C. daliensis is most similar to C. affinis Shaw, but the former can be distinguished by its smaller size and that frons entirely costate (only laterally costate in C. affinis) and prosternum without median groove (prosternum with median groove in C. affinis). Carminator daliensis is also similar to C. ater in having frons entirely costate, but the vertex is largely smooth with sparse punctures and the dorsal carina of subantennal groove is present. Geographically, C. daliensis is close to C. affinis from Malaysia and C. ater from Thailand (Shaw 1988). According to Mita and Konishi (2011), Carminator is a monophyletic taxon, with C. affinis as the sister group to the rest of the genus. So, the discovery of C. daliensis and its morphological similarity to C. affinis might serve as additional evidence that the common ancestor of the extant Carminator species was probably present in the Oriental-Australian transition zone and subsequently species dispersed northward as far as Japan (Mita and Konishi 2011).
So far, including the E. hainanensis described here, Ettchellsia species have mainly been found in the Indomalayan region (Mita and Shaw 2012). Unidentified species of Ettchellsia were reported from Taiwan (Shaw 1990b;Vilhelmsen et al. 2010) where the northernmost record of the genus is located. Further biogeographical and phylogenetic analyses of Ettchellsia will be desired in the future when additional new species and distributional records are found.