A complete diagnosis of the genus has been recently provided by Nugroho et al. (2016) and is therefore not repeated here.

(deposited in IEBR). Vietnam: ♀; Vinh Phuc province, Ngoc Thanh, Me Linh; 21°23'N, 105°42'E, 50 m a.s.l.; 18 April 2013; Nest-13-ML-Eu-03; D. T. Hoa leg.

Figures 1–6. 

Calligaster inflata sp. nov. 1 head, frontal view 2 head, dorsal view 3 mesosoma, dorsal view 4 propodeum, dorsal view 5 head and mesosoma, lateral view 6 metasomal tergum I, dorsal view. Scale bars: 1 mm.

This species can be distinguished from congeners by the following combination of characters: Head in frontal view with inner compound eye margins 1.1 times further apart from each other at clypeus than at vertex. Clypeus in frontal view wider than high, about 1.3 times as wide as high, apical margin produced and round medially. Propodeum deeply excavated medially, with the excavation nearly two-fifths of propodeal width and its margins marked laterally by ridges, dorsal surface largely smooth, with some sparse strong punctures near concavity, posterior and lateral surfaces bordered by blunt edge. First metasomal tergum with a median longitudinal carina and next to this on each side consisting of a few rows of quite elongate punctures, this part occupying one-third the width of the tergum, the other area on tergum with strong and sparse punctures, interspaces between punctures smooth and usually larger than their diameter; tergum II with small and sparse punctures, interspaces between punctures much larger than puncture diameter, about 3 to 4 times larger than their diameter.

Holotype. Female (Fig. 9). Body length (head + mesosoma + first two metasomal segments) 20 mm; forewing length 17 mm.

Figures 7–9. 

Calligaster inflata sp. nov. 7 metasoma, lateral view 8 metasomal terga II–VI, dorsal view 9 habitus, laterodorsal view. Scale bars: 1 mm.

Body black except two faint yellow spots on frons just above antennal toruli, dark ferruginous marks near apical margin and at base of mandible, and dark brown propodeal valvula. Wings subhyaline, veins brown.

Body covered with dense, suberect, golden setae on head, mesosoma, and metasomal segment I, and black setae on metasomal segments II–VI; setae longer on metanotum and dorsal surface of propodeum than on other body parts. Clypeus with coarse punctures, punctures in middle tend to unite and form large longitudinal punctures, with interspace strongly raised to form reticulations; frons with dense, deep, flat-bottom punctures, interspaces between punctures narrower than their diameters and raised to form reticulation; vertex less densely punctate, interspaces between punctures usually narrower than their diameter and not raised to form reticulations; punctures on gena dense, strong, well-defined, gena with a smooth band along occipital carina running from near base to near vertex. Pronotum, mesoscutum, and metapleuron with dense coarse punctures, punctures larger than punctures on frons; mesoscutum with some smooth areas between punctures medially, with deep parapsidal furrows running from apical margin to mid length, and two short and shallow longitudinal furrows laterally; punctures on mesoscutellum similar to those near apical margin of mesoscutum; metanotum with a shallow furrow medially, punctures smaller than those on mesoscutum; margins of concavity of propodeum marked laterally by ridges, propodeum with deep longitudinal fovea medially running from base to mid length of propodeum, with a short longitudinal carina running from fovea to apical margin, rugosely striated area occurring along two sides of fovea and carina; dorsal surface of propodeum largely smooth, with some sparse strong punctures near concavity; lateral surface of propodeum with strong, dense, well-defined punctures, interspaces between punctures smooth but raised to from carina apically; apical margin above valvulae round. First metasomal tergum with a median longitudinal carina bordered on each side by a few rows of quite elongate punctures, this part occupying one-third width of tergum, other area on tergum with strong sparse punctures, interspaces between punctures smooth and usually larger than their diameter; tergum II with small sparse punctures, interspaces between punctures much larger than puncture diameter, about 3 to 4 times larger than their diameter; punctures on terga III–V larger and denser than punctures on tergum II; punctures on tergum VI sparse but larger than punctures on tergum II; punctures on sternum II larger and denser than on tergum II; punctures on sterna III–V larger and denser than on sternum II.

Head : In frontal view 1.1 times as wide as high (Fig. 1), in dorsal view 1.7 times as wide as long. Vertex well developed, strongly produced behind compound eye, without cephalic fovea (Fig. 2). Distance from posterior ocelli to apical margin of vertex about 2.3 times distance from posterior ocelli to inner compound eye margin (Fig. 2). Occipital carina incomplete, evanescent dorsally, weakly widened laterally, slightly produced at one-third length from base (Fig. 5). Inner compound eye margins in frontal view 1.1 times further apart from each other at clypeus than at vertex (Fig. 1). Clypeus in frontal view wider than high, about 1.3 times as wide as high, apical margin produced and round medially (Fig. 1); in lateral view disc of clypeus gradually and weekly convex from base to near apical margin, then depressed to apical margin. Mandible with four prominent teeth. Antennal scape about 4.7 times as long as its maximum width; flagellomere I about 1.5 times as long as its maximum width, flagellomere II as wide as long, flagellomeres III–IX wider than long, terminal flagellomere bullet-shaped, about 1.2 times as long as its basal width.

Mesosoma : About 1.1 times as wide as head and 1.1 times longer than wide in dorsal view. Pronotal carina complete, raised into low lamella, angulate at lateral corner before attaining dorsal part, reaching ventral corner of pronotum. Mesoscutum slightly convex, shorter than wide, 0.9 times as long as wide between tegulae (Fig. 3). Disc of mesoscutellum rectangular, nearly flat, with lateral margin truncate. Disc of metanotum weakly produced posteromedially. In lateral view, mesoscutellum at same level as mesoscutum (Fig. 5). Propodeum deeply excavated medially (Fig. 4), with excavation nearly two-fifths of propodeal width and its margins marked laterally by ridges, posterior and lateral surfaces bordered by blunt edge.

Metasoma : Metasomal tergum I in dorsal view strongly widened after short, basal, parallel-sided part to one-third basally, then gradually narrowly to apical margin (Fig. 6), 1.4 times as long as wide, in lateral view strongly convex from base to apical margin. Metasomal segment II petiolate at base (Figs 7, 8), tergum II in dorsal view wider than long, 1.05 times as wide as long (Fig. 8), and shorter than tergum I; sternum II in lateral view straight from base to about one-half length, then straight to apical margin (Fig. 7), and slightly produced medially. Terga I–VI not raised and without lamellae (Figs 7, 8).

Nest. (Fig. 10). One nest of this species was collected at Me Linh Station for Biodiversity of the Institute of Ecology and Biological Resources (IEBR), Vinh Phuc Province on 23 March 2013. The nest consists of four cells, each bent at the neck and enlarged at the bottom. The inner diameter of the open end of cells varied from 5 to 6 mm. The oldest cell was strongly secured to a twig of a tree, and from its underside the second cell and then those following depend. The length of cells measured 35 to 36 mm. There was a well-defined roof covering the entrance of the cells (Fig. 10). The entrance of the cell was closed up with leaf-bits. Those plugs were concave and smooth surfaced on the outer side, rather crude on the inner surface. Three of them had a small hole on the wall of the cell and the remaining cell was intact. Three cells with a small hole on the wall were opened for examination of structural details. Unfortunately, they were empty except for their cocoons. The cocoon was 20 to 21 mm long. They were thickest in the part facing the open end of the cells and thinner at the wall of the cells. The feces and the prey remain were always at the bottom of the cells and positioned outside the cocoon. The intact cell was preserved and a female wasp emerged from it on 18 April 2013.

Figure 10. 

Calligaster inflata sp. nov. nest. Scale bar: 1 cm.

Vietnam (northern part).

The specific epithet is from the Latin inflatus (meaning swollen), and refers to the swollen metasomal segment I in this species.

The new species is similar to C. himalayensis in that both have the clypeus, frons, and mesoscutum with coarse dense punctures, with interspaces between the punctures smaller than a puncture diameter and raised to form reticulation; and the lateral part of metasomal tergum I with strong sparse punctures. However, it differs from C. himalayensis in having metasomal tergum I about 1.4× as long as wide, with a median longitudinal carina and next to this on each side consisting of a few rows of noticeably elongate punctures, this part occupying one-third the width of the tergum (metasomal tergum I about 1.8× as long as wide, with a median longitudinal carina and next to this on each side consisting of a few longitudinal striae, this part occupying about half the width of the tergum in C. himalayensis); and body punctures larger and coarser than in C. himalayensis.

This species was recorded from Vietnam by Nguyen et al. (2014) and Nugroho et al. (2016). The species occurs in the northern and central parts, as well as the Tay Nguyen highlands. Refer to Nugroho et al. (2016) for the diagnosis of this species.

Vietnam: 1♂, Cao Bang, Nguyen Binh, Thanh Cong, 22°32.5'N, 105°53'E, alt. 1000 m, 8 Aug. 2012, Lien Thi Phuong Nguyen et al. leg.; 1♀, Cao Bang, Tra Linh, Ho Thang Hen, 22°45'47.5"N, 106°53'35.7"E, alt. 619 m, 20 May 2023, Lien Thi Phuong Nguyen, Ngat Thi Tran, Cuong Quang Nguyen leg.; 1♀, 1♂, Tuyen Quang, Ham Yen, Phu Luu, Cham Chu NP, alt. 200 m, Jun. 2011, Lien Thi Phuong Nguyen leg.; 1♀, Son La, Moc Chau, Chieng Son, Chieng Ve, 21 Jun. 2015, Long Dang Khuat leg.; 1♀, Dien Bien, Dien Bien, Pa Thom, 20°17'50"N, 102°54'37"E, alt. 693 m, 01 Mar. 2023, Hoa Thi Dang leg.; 1♀, 1♂, Dien Bien, Tua Chua, Muong Fang, 21°50'46"N, 103°22'53"E, alt. 735 m, 04 Mar. 2023, Hoa Thi Dang leg.; 1♂, Vinh Phuc, Me Linh, Me Linh Station, 25 May 2013, Nest#ML-2013-Eum 1, Lien Thi Phuong Nguyen leg.; 1♀, Vinh Phuc, Me Linh, Me Linh Station, 2 Jun. 2018, Cuong Quang Nguyen leg.; 1♀, 1♂, Vinh Phuc, Me Linh, Me Linh Station, 01 Jul. 2020, Hoa Thi Dang leg.; 1♂, Hoa Binh, Ngo Luong, Ngoc Son NR, 20°25'13.3"N, 105°18'36"E, alt. 200 m, 27 Aug.2020, Ngat Thi Tran leg.; 1♂, Thanh Hoa, Ba Thuoc, Thanh Son, alt. 200 m, 16–18 Jun. 2003, Huong Thi Thu Nguyen leg.; 1♀, Thanh Hoa, Thuong Xuan, Van Xuan, Hon Can, Xuan Lien NP, 19°52'27.5"N, 105°14'20.8"E, alt. 106 m, 24 Aug. 2012, Lien Thi Phuong Nguyen leg.; 1♂, Thanh Hoa, Quan Hoa, Pu Hu NP, 20°29'13.3"N, 104°57'47.2"E, alt. 408 m, 13 Jun. 2016, Lam Xuan Truong, Dac Dai Nguyen, Ngat Thi Tran, Linh Ngoc Ha leg.; 1♀, Ha Tinh, Vu Quang NP, 18°17'45"N, 105°22'29"E, alt. 78 m, 12 Jun. 2023, Cuong Quang Nguyen, Lien Thi Phuong Nguyen, Ngat Thi Tran leg.; 1♀, Quang Nam, Song Thanh, Cha Vai, alt. 400–600 m, 29 Apr. 2005, collectors from the Insect Systematic Department (IEBR) leg.; 1♀, Kom Tum, Dak Ha, Dak Mar, Dak Uy SUF, 14°33'04.6"N, 107°55'08.0"E, 19 Jun. 2012, alt. 630 m, Lien Thi Phuong Nguyen leg.; 3♂♂, Gia Lai, Chu Se, 14 Apr. 2013, Lien Thi Phuong Nguyen leg.; 1♀, Gia Lai, KBang, Kon Chu Rang NR, 14°31'10.4"N, 108°36'24.9"E, 6 Sep. 2018, Lam Xuan Truong, Tuan Viet Luong leg.; 1♀, Dak Lak, Buon Me Thuot city, Tan Hoa, 28 Jul. 2020], QH-L22-01, Bui Thi Quynh Hoa leg., 2♀♀, Dak Nong, Dak Giong, Dak Som, Ta Dung NP, 11°50'16.1"N, 107°59'16.7"E, alt. 475 m, 6 May 2016, Nest#VN-TN-2016-E-01, Lien Thi Phuong Nguyen, Dai Dac Nguyen, Ngat Thi Tran leg.

The male genitalia of this species were described by Giordani Soika (1960) but are redescribed here with added detail.

Male genitalia. As in Figs 16–19. Parameral spine with setae (Fig. 16). Volsella flattened, wide on inner aspect, without setae at top (Fig. 16). Digitus gradually narrow from base to apex, with round apex, with setae on apical half (Fig. 17). Penis valve (Fig. 18), about 1.9 times as long as basal apodeme, in profile apical part strongly produced into a large pointed lobe (Fig. 19), with apical part smooth (Fig. 19), middle rod slightly shorter than basal apodeme (Figs 18, 19).

Figures 11–15. 

Calligaster himalayensis 11, 13–15 female 12 male 11 head, frontal view 12 head, frontal view 13 mesoscutellum, metanotum, and propodeum, dorsal view 14 metasomal tergum I, dorsal view 15 metasomal terga II–VI, dorsal view. Scale bars: 1 mm.

Figures 16–21. 

Calligaster himalayensis. 16–19 male genitalia 16 inner aspect of paramere with volsella and digitus 17 volsella and digitus 18 aedeagus, ventral view 19 aedeagus, lateral view 20–21 adult and nest. Scale bars: 1 mm.

Nest. Three nests comprising 15 cells of this species were collected at Me Linh Station for Biodiversity of the Institute of Ecology and Biological Resources (IEBR), Vinh Phuc Province on 1^st July 2020. These nests were made on the branch of bougainvillea. They were not only protected by the roof like the nest of C. inflata, but the entire nests were covered with leaves (Fig. 21). The detailed structure of these nests was similar nest of C. inflata: the nests consisted of four to six cells, each bent at the neck and enlarged at the bottom; the inner diameter of open end of cells varied from 6 to 6.5 mm; the oldest cell was strongly secured to a twig of a tree, and from its underside the second cell and then those following depend; the entrance of the cell was closed up with leaf-bits; those plugs were concave and smooth surfaced on the outer side, rather crude on the inner surface. The length of the cells measured 32 to 40 mm. Among 15 cells in three nests examined, three individuals developed to the mature stage (two females and one male), other 12 cells died. Of 12 dead cells, three died at the larval stage for unknown reasons; six cells with a small hole in the wall and they were empty except for their cocoons; the other three cells containing prepupae were attacked by an eulophid species. The cocoon was 20 to 22 mm long. They were thickest in the part facing the open end of cells and thinner at the wall of the cells. The feces and the prey remain were always at the bottom of the cells and positioned outside the cocoon.

India: Sikkim; China: Guangdong, Hong Kong; Laos; Vietnam.