Cotesia ruficrus ( Haliday, 1834 )

Fagan-Jeffries, Erinn P. & Austin, Andrew D., 2020, Synopsis of the parasitoid wasp genus Cotesia Cameron, 1891 (Hymenoptera: Braconidae: Microgastrinae) in Australia, with the description of seven new species, European Journal of Taxonomy 667 (667), pp. 1-70 : 45-48

Cotesia ruficrus ( Haliday, 1834)

Figs 3A , 4A , 26–27

Microgaster ruficrus Haliday, 1834: 253 (lectotype, ♀, NMI).

Apanteles antipoda Ashmead, 1900: 355 .

Apanteles sydneyensis Cameron, 1911: 342 .

Apanteles sydneyensis – Wilkinson 1928a: 95 (synonymised with A. antipoda ).

Apanteles antipoda – Wilkinson 1928a: 95; 1929: 108 (synonymised with Apanteles ruficrus ).

Cotesia ruficrus – Mason 1981: 113 (transferred from Apanteles s.l.).

For a full list of synonyms and bibliography, see Shenefelt (1972: 617), Yu et al. (2016) and Fernández-Triana et al. (2020).

Diagnosis

Cotesia ruficrus can be separated from all other species of Cotesia currently described from Australia and Papua New Guinea by the following combination of characters: T1 consistently broadening posteriorly, wedge shaped; scutellar disk with strong punctures; T3 with only a single row of setae in posterior half.

Material examined

Syntypes of A. sydneyensis

AUSTRALIA • 4 ♀♀; New South Wales, Sydney; parasitic on Plusia Ochsenheimer, 1816 caterpillar; bred Jun. 1902 [by W.W. Froggart]; NHMUK 3.c.999 .

Other material

AUSTRALIA – New South Wales • 1 ♀; Eden, Bungo Street ; 21–27 Dec. 2005; C. Stephens leg.; M/T in exotic native garden blend nr eucalypt forest; COI BOLD: AUMIC289-18; WINC • 1 ♀; Kosciuszko NP ; 3.6 km SW of Thredbo, nr Dead Horse Gap; 11–13 Jan. 2004; C&M&N Lambkin and NT Starick leg.; ANIC bulk sample 2217; 36°32′26″ S, 148°15′52″ E; M/T; 1500 m a.s.l.; COI BOLD: AUMIC472-18; ANIC 32 130230 . – Queensland • 1 ♀; Bookstead ; 3 Dec. 1986; I.J. Titmarsh leg.; ex. fifth instar H. armigera on maize; WINC . – South Australia • 1 ♂; Goolwa ; coll. 15 Nov. 85; T. Prance leg.; ex. army worms on oats; pupated 2 Dec. 85, emerged 9 Dec. 85; WINC • 1 ♂; Goolwa; 15 Nov. 85; T. Prance leg.; ex. army worms on oats; pupated 2 Dec. 85, emerged 9 Dec. 85; WINC . – Western Australia • 1 ♀; Kununurra; 16 Sep. 79; reared in lab ex. Pseudaletia convecta ; WINC • 1 ♀; Harvey ; em. 6 May 1983; C. Boyd; leg.; ex. Agrotis ipsilon [on] millet; WINC .

Distribution

Cosmopolitan, see Fernández-Triana et al. (2020) for global distribution. In Australia: NSW (record from types of A. antipoda and A. sydneyensis ), WA, S. Aust, Qld (records from examined material), Tas (record from Austin & Dangerfield 1992).

Host

Agrotis sp. ( Noctuidae ). Record from original description of A. antipoda . Plusia sp. ( Noctuidae ): record from specimens from original description of A. sydneyensis . Mythimna (Pseudaletia) convecta Walker, 1857 , Agrotis ipsilon (Hufnagel, 1766) , Helicoverpa armigera (Hübner, 1808) (Noctuidae) : records from examined material. Gregarious. Also known from a wide range of noctuid genera in Australia and across the world, including the problematic quarantine pest Spodoptera frugiperda (Smith, 1797) which has recently been identified to have arrived in Australia (see Shenefelt 1972: 617; Nixon 1974: 495; Austin & Dangerfield 1992: 22; Gupta et al. 2019; Yu et al. 2016 for a list of host genera).

Remarks

Cotesia ruficrus represents an interesting case, in which strains were introduced from Pakistan to Australia and New Zealand ( Cumber et al. 1977; Michael 1985) and possibly represent a different species to the native Apanteles sydneyensis , which was synonymised with the (also) native Apanteles antipoda by Wilkinson (1928a) and then with C. ruficrus ( Wilkinson 1929) . Until specimens are found which are distinct from the introduced C. ruficrus at a molecular level and morphologically identical to the types of A. sydneyensis or A. antipoda , we leave the synonymy with A. ruficrus intact, and assume the species to be cosmopolitan. We note that a similar situation occurred in the case of C. nonagriae and C. flavipes , where the two species were erroneously synonymised based on morphology and later discovered to be distinct species based on molecular evidence and subtle morphological differences ( Muirhead et al. 2008), thus excluding C. flavipes from the Australian fauna. Due the uncertainty surrounding whether this species is cosmopolitan, or consists of both introduced and native unrelated lineages, we do not redescribe the species and provide only a diagnosis that encompasses both the examined types of A. sydneyensis and the sequenced specimens that are placed in a COI tree with northern hemisphere C. ruficrus specimens.

In the key of Nixon (1974), C. ruficrus is differentiated from C. vestalis by the character of the third tergite having setae restricted more or less to a single row on the anterior half of the segment (as opposed to third tergite being covered all over with fine setae, except for small mid-basal area). In the Australian specimens, the presence of only a single row of setae in C. ruficrus is valid, but it is not always in the anterior half of the tergite (more often in the posterior half). Additionally, Nixon (1974) notes that in C. ruficrus the scutellum has punctures, at least on anterior half, wide enough apart to leave smooth shiny interspaces fully equal to width of punctures, whist in C. vestalis there are no smooth interspaces anteriorly. In the specimens of C. vestalis examined for this study, there was variability in this character and some specimens had sculpturing resembling that of C. ruficrus – hence this character is not used in the key presented here.

Figures

Fig. 3. A. Cotesia ruficrus (Haliday, 1834), scutellar disk (ANIC 32 130230). B. C. rufiventris (Bingham, 1906), scutellar disk (paralectotype NHMUK).

Fig. 4. A. Cotesia ruficrus (Haliday, 1834), T3 (ANIC 32 130230). B. Cotesia vestalis (Haliday, 1834), T3 (WINC).

Fig. 26. Cotesia ruficrus (Haliday, 1834), syntype of C. sydneyensis (Cameron, 1911) (NHMUK 3.c.999). A. Habitus in dorsal view and fore wing B. Enlarged section of A showing propodeum and T1–2.

Fig. 27. Cotesia ruficrus (Haliday, 1834), ♀ (ANIC 32 130230) A. Habitus in lateral view. B. Habitus in dorsal view. C. Fore wing.