Cotesia invirae Salgado-Neto & Whitfield, 2019

Salgado-Neto, Geraldo, Whitfield, James Bryan & Garcia, Flávio Roberto Mello, 2019, Cotesia invirae, sp. nov., from South Brazil: a new gregarious microgastrine wasp (Hymenoptera: Braconidae) reared from Opsiphanes invirae (Nymphalidae) feeding on palms, Revista Brasileira de Entomologia (Rev. Bras. Entomol.) 63 (2), pp. 136-140 : 137-139

Cotesia invirae Salgado-Neto & Whitfield , sp. nov.

( Figs. 1 and 2 )

Holotype. Female, Brazil: Rio Grande do Sul, Santa Maria, Universidade Federal de Santa Maria ( UFSM) (29 ◦ 42 l 19 llS, 53 ◦ 42 l 57 llW – 90 m. elev.).Deposited in the Collection of Entomophagous Insects “Oscar Monte” of the Instituto Biológico de Campinas, São Paulo. ( IB-CBE; Valmir Antônio Costa curator), number IB-CBE #215-C, GSAL 10.01.2006 and also deposited in the Hymenoptera collection of the Museum of Zoology of the University of São Paulo ( MZUSP; Carlos Brandão curator), number MZSP 62057, September 2018, coll. G. Salgado-Neto, ex larva Opsiphanes invirae (Huebner, 1818) ( Lepidoptera : Nymphalidae ).

Paratypes. 2 males, deposited in MZUSP, numbers MZSP62066 and MZSP62067 . Same data as holotype .

Diagnosis. The combination of characters presented below is sufficient to separate C. invirae from all other described native species of Cotesia for the Neotropical region. In particular, few neotropical Cotesia have the anterior metasomal tergites largely orangish rather than black (and even those are mostly undescribed). However, several widespread agricultural species, C. marginiventris (Viereck) and C. flavipes (Cameron) , have current distributions extending into Brazil and are known to be highly variable in tergite colour. C. marginiventris differs in having the anterior margin (roughly 1/3 of length) of tergite 3 with rougher sculpture (smooth in C. invirae ), and C. flavipes (along with other members of its species complex) is extremely distinctive in having a relatively depressed mesosoma that is usually significantly narrower in dorsal view than the width of the head (in addition to having the face somewhat bulging below the antennae in lateral view). C. alius , previously recorded from the same host, has essentially black tergites, although the laterotergites are bright yellowish as in C. invirae . C. alius also appears to have a slightly longer first tergite than C. invirae , but otherwise the two species are quite similar morphologically.

Description. Female ( Fig. 1a ). Body colour: head and mesosoma mostly black except pale, almost whitish palpi, most of all legs honey-yellow except darkened junction of trochanter with femur, distal quarter of hind femur, distal 0.3–0.4 of hind tibia, and most of hind tarsus; metasoma mostly light honey-yellow to orange except dark brown first tergite and orange to brown second tergite. Antenna colour: scape, pedicel and flagellum dark. Tegulae colour: dark brown, relatively opaque. Pterostigma colour: dark greyish brown. Fore wings colour: partially pigmented but pigmented veins dark brown (a few veins may be dark but most pale). Antenna length/body length: antenna just slightly shorter than body (head to apex of metasoma). Body in lateral view: not distinctly flattened dorso-ventrally. Body length (head to apex of metasoma): 2.5 – 2.7 mm. Fore wing length: 2.4–2.6 mm. Ocular-ocellar line/posterior ocellus diameter 1.7–1.9. Interocellar distance/posterior ocellus diameter: 1.9–2.1. Antennal flagellomere 2 length-width: 2.9–3.1. Antennal flagellomere 14 length/width 1.4–1.6. Length of flagellomere 2/length of flagellomere 14: 2.2–2.3. Metafemur length/width 3.0–3.2. Metatibia inner spur length/metabasitarsus length: roughly 0.5–0.6. Anteromesoscutum: anteriorly with distinct dense punctures, with only a very narrow smooth band posteriorly anterior to scutoscutellar sulcus. Mesoscutellar disc: sparsely punctured and mostly shiny. Number of pits in scutoscutellar sulcus: 8–10. Propodeum carina: with complete medial longitudinal carina that is nearly obscured by coarse background suggesting medial areola. Propodeum background sculpture: mostly coarsely rugulose. Mediotergite 1 length/width at widest point: 1.0–1.1. Mediotergite 1 shape: evenly widening from anterior margin to 0.8–0.9 of mediotergite length (widest point), then rounding towards posterior margin. Mediotergite 1 sculpture: mostly rugulose except anteromedially smooth. Mediotergite 2 nearly quadrate with width at posterior margin/length: 2.1–2.3. Mediotergite 2 sculpture: mostly rugose, smoewhat polished laterally. Hypopygium: evenly sclerotized but folded medially, posteriorly forming a strongly obtuse angle in lateral view. Ovipositor thickness: tapering gradually to tip. Ovipositor sheaths: short, approximately 1/3 of hind tibia length but only slightly exposed towards tip. Length of fore wing veins r/2Rs: 1.0–1.1. Pterostigma length/width 2.0–2.2. Point of insertion of vein r in pterostigma: just beyond half way point of pterostigma length. Angle of vein r with fore wing anterior margin: angling 5–10 degrees towards wing tip posteriorly. Shape of junction of veins r and 2RS in forewing: r weakly arched, junction distinctly angled.

Molecular data. COI barcode deposited in GenBank (Accession MK040535). When the Barcode of Life Database (BOLD) was interrogated with this sequence, the closest matches (between 1 and 2% sequence divergence) were two currently undescribed species from the Janzen and Hallwachs ACG project ( Janzen et al., 2009). Both of these species were reared from Opsiphanes on palms (albeit different species). They are referred to informally as Cotesia Whitfield 78 and Cotesia Whitfield 20 in Smith et al. (2008). As C. alius is also from the same basic host group, it appears that there is an international cluster of closely related species, still mostly undescribed, to be sorted out eventually based on a broad study.

Host: Opsiphanes invirae (Huebner, 1818) ( Lepidoptera : Nymphalidae ).

Biology/ecology. Cotesia invirae is a gregarious parasitoid wasp that occurs mainly in the wet season (March–May); however, its host, O. invirae , occurs throughout the year, mainly in the autumn season (March–April–May). Cotesia invirae larvae kill the host larva before the end of the last instar and form their cocoons in regular mass of dirty whitish cocoons, regularly arranged under the host. The larvae of this gregarious species all emerge from the host in a short time through many different holes in the host cuticle and spin a common woolly cocoon mass, within which the individual cocoons can be distinguished. Some previous records attributed to C. alius (e.g. Salgado-Neto, 2013) actually refer to this new species.

Based on 35 analyzed reared broods, each one referring to a larva of O. invirae from nature, were 4581 registered cocoons, averaging 130.88 ± 49.02 per host. Taking into account that the number of cocoons is the number of eggs laid per host-larva, whose average number of eggs laid was 87. Based on seven broods, with a total of 789 cocoons (112.71 ± 31.21 cocoons/posture), it was found that 104 cocoons (13%) from two broods of C. invirae were parasitized by Eulophidae . We observed four species of hyperparasitoids ( Eulophidae ) exploiting the cocoon mass of C. invirae collected in the field, two from the Entedoninae ( Horismenus opsiphanis Schrottky, 1909 and Horismenus sp. nov.) and two from Tetrastichinae ( Oomyzus sokolowskii Kurdjumov, 1912 and Aprostocetus sp. nov.). All hyperparasitoids were identified by Dr. Christer Hansson (Lund University, Sweden) and Dr. Valmir Antonio Costa (Instituto Biológico de Campinas, Brazil) ( Salgado-Neto & Di Mare, 2010).

Distribution. Known so far from Santa Maria, Rio Grande do Sul, Brazil.

Etymology. The specific epithet invirae , from the Latin meaning turn around, (the same as: bickering, return, bend, reverse, spin, put yourself in a new position) is a reference to Opsiphanes invirae (Huebner, 1818) ( Lepidoptera : Nymphalidae ) in tribute to the movement of the host caterpillar to avoid the oviposition of parasitoids.

Figures

Fig. 1. (a) Lateral view of female Cotesia invirae; (b) view of the labrum, mandibles and labial palps; (c) front view of the face; (d) lateral view of the antenna; (e) dorsal view of the mesosoma; (f) dorsal view of abdomen; (g) view of the forewing in situ; (h) details of the spurs of the tibia (inner and outer); (i) larvae of C.invirae; (j) front view of the pupa of C. invirae; (k) dorsal view of pupa of C. invirae; (l) lateral view of the pupa of C. invirae; (m) front view of head, the larvae of C. invirae; (n) view of the cocoons of C. invirae, arranged regularly and secured with silk threads to each other in the form of palisades on the host. Some material here previously reported in Salgado-Neto (2013) as from C. alius.

Fig. 2. (a) Dorsal habitus of female Cotesia invirae, showing sculpturing of mesoscutum, scutellum, propodeum and anterior metasomal tergites; (b) lateral habitus of C. invirae; (c) wings of C. invirae.