Oomyzus spiraculus Song, Fei & Cao, 2020

Song, Hai-Tian, Fei, Ming-Hui, Li, Bao-Ping, Zhu, Chao-Dong & Cao, Huan-Xi, 2020, A new species of Oomyzus Rondani (Hymenoptera, Eulophidae) reared from the pupae of Coccinella septempunctata (Coleoptera, Coccinellidae) in China, ZooKeys 953, pp. 49-60 : 49

publication ID

https://dx.doi.org/10.3897/zookeys.953.53175

publication LSID

lsid:zoobank.org:pub:9333142A-07FB-4265-9D24-920751ECA286

persistent identifier

https://treatment.plazi.org/id/B57F37F6-51E7-4EC3-A9DA-9541DBC2DC2E

taxon LSID

lsid:zoobank.org:act:B57F37F6-51E7-4EC3-A9DA-9541DBC2DC2E

treatment provided by

ZooKeys by Pensoft

scientific name

Oomyzus spiraculus Song, Fei & Cao
status

sp. nov.

Oomyzus spiraculus Song, Fei & Cao sp. nov. Figures 1 View Figure 1 , 2 View Figure 2 , 3 View Figure 3

Female.

Body length 1.2-1.4 mm. Body black with more or less dark green tinge (Fig. 1a, b View Figure 1 ). Antenna brown with apical scape and pedicel more or less light brown ventrally. Legs with coxae brown, tips of femora broadly brown and tibiae pale yellow; fore tarsus fuscous, turning to brown towards tarsomere 4; mid and hind tarsi with tarsomeres 1+2 pale yellow and tarsomeres 3+4 brown (Fig. 2a-c View Figure 2 ). Wings hyaline, with brown veins (Fig. 2h View Figure 2 ).

Antenna (Figs 1b View Figure 1 , 3f View Figure 3 ) with 3 funiculars and 3 clavomeres; scape nearly reaching median ocellus, scape with raised and longitudinal reticulation; pedicel slightly shorter than F1, with raised striations; F1-F2 subequal in length and each about 1.4 × as long as broad, F3 longer and more slender than F1 and F2, about 1.6 × as long as broad; clava 0.7-0.8 × as long as funicle, clavomeres decreasing in length, clavomere 3 with a short and indistinct terminal spine. Each flagellomere with longitudinal sensilla and apically with a circle of scattered, mushroom-shaped capitate peg sensilla; each flagellomere except clavomere 3 truncate apically.

Head slightly broader than mesoscutum, and very easily collapsing when dried. OOL 1.58 × POL (0.70: 0.44) (Fig. 3g View Figure 3 ). Ocelli arranged in an obtuse triangle (Fig. 3g View Figure 3 ), almost in a line if head is collapsed. Ocellar triangle slightly raised. Head in anterior view 1.23 × as broad as high (2.7: 2.2), with vertex convex (Fig. 3h View Figure 3 ). Frons with a short and narrow V-shaped frontofacial suture connecting to ocellar area; upper face with a thin and raised carina between depressed scrobes; head easily collapsed along frontofacial sutures and outer margins of scrobes (Fig. 3h View Figure 3 ). Face with longitudinal reticulation, scrobes with indistinct reticulation. Toruli inserted slightly above lower margin of eyes. Eyes with short and sparse white hairs, diameter larger than malar space. Malar space 0.8-0.9 × as long as mouth opening, and malar sulcus more or less straight. Anterior margin of clypeus weakly bilobed (Fig. 3h View Figure 3 ).

Pronotum strongly sloping and almost invisible in dorsal view; pronotum distinctly reticulate, neck and collar not delimited, without posterior carina (Fig. 3a, b View Figure 3 ). Mesoscutum with engraved and longitudinal reticulation, notaular grooves deep and curved; MLM with 3 adnotaular setae, without median line or with a trace of median line only posteriorly, with posterior margin straight (Fig. 3b View Figure 3 ). Axillae strongly shifted forward, with engraved reticulation in anterior 2/3 and with strongly raised striations, like carinae, in posterior 1/3 (Fig. 3b View Figure 3 ). Scutellum convex in profile, slightly broader than long (1.3: 1.2), with engraved, longitudinal reticulation; scutellum with distinct submedian lines that are slightly nearer to sublateral lines than to each other, enclosed space between submedian lines 2.1-2.2 × as long as broad; with two pairs of setae on scutellum, subequal in length, anterior pair situated slightly before middle and posterior pair situated near posterior margin; scutellum with depressed frenum, delimited by groove and scattered, irregular carinae (Fig. 3b, d View Figure 3 ). Dorsellum about 2.6 × as broad as long, with coarser engraved reticulation than scutellum; slightly incised in middle of posterior margin; lateral panel of metanotum smooth, with a carina medially (Fig. 3b, c View Figure 3 ). Propodeum incised medially along anterior and posterior margins, thus shortest medially, medially slightly longer than dorsellum; propodeum with median carina, broadening caudad and then extending laterally; propodeum with paraspiracular carinae, median area, delimited by paraspiracular carinae and median carina, with slightly raised reticulation and with irregular oblique carinae posteriorly (Fig. 3b, c View Figure 3 ); spiracles with entire rim exposed; callus reticulate, with 4 setae. Lateral panel of pronotum, prepectus, mesepimeron and mesepisternum reticulate, except a small area between mesepimeron and mesepisternum that is smooth; acropleuron smooth; metapleuron reticulate (Fig. 3d View Figure 3 ).

Petiole short and hidden (Figs 1a View Figure 1 , 3e View Figure 3 ). Gaster (Fig. 3e View Figure 3 ) 1.2-1.6 × as long as broad and easily collapsed, especially Gt2-4 easily shrink or expand after death, and thus the relative length of mesosoma and metasoma is variable; gastral tergites each with weak raised reticulation; Gt7 with 4 cercal setae, the longest seta slightly longer than the other three setae that are subequal in length.

Legs (Fig. 2a-c View Figure 2 ) short and stout, with coxae, femora, and tibiae reticulate; tarsomere 1 of mid and hind legs almost as long as tarsomere 2. Fore wing (Fig. 2h View Figure 2 ) with postmarginal vein absent; submarginal vein with 1 seta on dorsal surface; speculum small, closed below, hardly extending below marginal vein.

Male.

Body length about 1 mm (Fig. 1c, d View Figure 1 ). Differs from female as follows. Antenna (Figs 2g View Figure 2 , 3i View Figure 3 ) with 4 funiculars and 3 clavomeres, scape and pedicel black, funicle and clavomere 1 brownish yellow, remainder of clava black; scape with ventral plaque 0.57 × total length of scape; F1 1.25 × as broad as long, distinctly shorter than pedicel and F2; F2-F4 slender, subequal in length, 1.85-2 × as long as broad; clava slightly broader than funicle, about 2.6 × as long as broad, shorter than combined length of F3 and F4; each funicular with a compact subbasal whorl of dark setae which reach beyond tip of flagellomere attached to. Fore tarsi less infuscate (Fig. 2d View Figure 2 ). Gaster distinctly pointed apically (Fig. 3j View Figure 3 ).

Etymology.

From the Latin word spiraculus (spiracle), referring to the propodeum with paraspiracular carinae.

Type material.

Holotype ♀, China, Jiangsu, Nanjing, Baima Agricultural Field of Nanjing Agricultural University, 30.V.2019, coll. Minghui Fei, ex. pupa of Coccinella septempunctata L. (IZCAS, IOZ(E)225734). Paratypes: 5♀ 4♂, same data as holotype (IZCAS, IOZ(E)225735-IOZ(E)225742; NAU); 8♀ 3♂, China, Jiangsu, Nanjing, V.2019, coll. Haowu Hu, ex. pupa of Coccinella septempunctata L., lab reared on the pupae of Coccinella septempunctata (IZCAS, IOZ(E)225743-IOZ(E)225753; NAU).

Additional material.

3♀ 3♂ on slides, China, Jiangsu, Nanjing, V.2019, coll. Haowu Hu, ex. pupa of Coccinella septempunctata L., lab reared on the larva-pupa of Coccinella septempunctata (IZCAS).

Host and offspring information.

This species was reared as a gregarious endoparasitoid from pupae of C. septempunctata . In the laboratory, each instar of the host larva could be parasitized and would pupate successfully when provided with adequate number of aphids. The parasitoid offspring emerged from the host pupa, after a development time of 14-18 days. The brood size ranged from 4-23 after a single bout of parasitization, and the male number ranged from 0-3, mostly 2 (n =28). Another two common ladybird species, Harmonia axyridis Pallas and Propylaea japonica (Thunberg), were also included in the study and the result showed that the Japanese lady beetle, P. japonica , was a potential host.

Distribution.

China: Jiangsu.

Remarks.

Oomyzus spiraculus is one of five species of Oomyzus known to have propodeum with distinct paraspiracular carinae; the other four are O. hemerobii , O. rujumensis , O. propodealis , and O. sempronius . However, O. spiraculus is currently not supported to form a species group with any above-mentioned species by any other evidence. Morphological similarities and differences among these species are summarized in Table 1 View Table 1 .

In addition, the relatively short propodeum with paraspiracular carinae and the pale-yellow tibiae differentiate O. spiraculus from O. scaposus reared from the same host (Table 1 View Table 1 ). Male tibiae of O. spiraculus are mostly pale yellow as the female, sometimes slightly infuscate dorsally.

Kingdom

Animalia

Phylum

Arthropoda

Class

Insecta

Order

Hymenoptera

Family

Eulophidae

Genus

Oomyzus