Asiobaccha tripartita (Walker, 1861) comb. nov.

(Figures 11c, d, f, 14d)

Baccha tripartita Walker, 1861: 285 . Holotype: ♂, BMNH. Type locality: Indonesia: Misool Island. Schiner 1868: 344; Bigot 1892: 166; Wulp 1896: 121; Kertész 1910: 157.

Baccha flavipes Doesburg, 1959: 233 . Syn. nov.

Baccha sulica Austen, 1893: 144 (in part). Syn. nov. Wulp 1896: 121; Kertész 1910: 157.

Baccha (Allobaccha) sulica of Knutson et al. 1975: 323 (in part).

Baccha (Allobaccha) tripartita of Knutson et al. 1975: 323.

Baccha papuana Hull, unpublished of Greve and Ismay 1983: 74.

Episyrphus (Asiobaccha) sulica of Thompson and Vockeroth 1989: 443 (in part).

Episyrphus (Asiobaccha) tripartita of Thompson and Vockeroth 1989: 443.

Allobaccha flavipes of Thompson and Vockeroth 1989: 441.

Allobaccha papuana (Hull, unpublished name) of Rojo et al. 2003: 20.

Differential diagnosis

This species has a yellow face (Figure 11f), the alula is bare, narrower than costal cell, the wing is partly bare basally (Figure 14d), and it does not have a mesonotal fringe. The abdominal pattern is identical to that of two other species, A. bicolor and A. loriae, with tergum 4 entirely black (Figure 11c, d), but differs by the wing microtrichia as stated in the key. Asiobaccha bicolor and A. tripartita differ from A. loriae by having the wing bare basally, easy to distinguish because both always have the cell CuP and anal lobe partly bare basally (Figure 14c, d); sometimes A. loriae specimens may have very small bare areas in the cell BM but the cell CuP and the anal lobe are always microtrichose. On the other hand, A. tripartita has a more extensive microtrichia and bare basal areas of the wing are on basal 1/3 – 1/2 cell BM only (Figure 14d), while A. bicolor has the cell R bare on basal 1/3 – 1/2 and the cell BM bare on basal 1/2 or more (Figure 14c).

Variation. Wing microtrichia is a bit less variable in this species: the bare area of cell BM varies between basal 1/3 to basal 1/2. Furthermore, a few specimens have costal cell bare very basally. The specimen from New Ireland has the scutum entirely yelloworange. Wing colouration varies from very dark to almost hyaline.

Length (N = 4). Body, 11.0 – 13.0 (12.3) mm; wing, 10.0 – 12.0 (11.1) mm.

Biology

Greve and Ismay (1983) mentioned one species of Baccha with the following information: ‘ Ex Tiracola (Lep., Noctuidae) larva, Brevaturu, N.P., August, 1971 ’. The species mentioned is Baccha ? [sic] papuana Hull. This record is compiled by Rojo et al. (2003) but with a different name, Allobaccha papuana (Hull, unpublished name).

In the opinion of this author, this species might refer to the unpublished name of Baccha papuana Hull that appears in two specimens from Mafulu kept at the BMNH and CNC, although there is no information in the original labels about Tiracola .

After studying the work of Greve and Ismay (1983), this citation may refer to a larva of a syrphid species parasiting a larva of Tiracola Moore, 1881 ( Lepidoptera: Noctuidae) from Barevaturu N.P. in Papua New Guinea. However, there is no species of Asiobaccha or Baccha that parasitises butterfly larvae. Consequently, this record by Greve and Ismay (1983) may not refer to a species of Baccha, Allobaccha or Asiobaccha, or, on the other hand, it might indicate that the larva of Baccha was preying on the Tiracola larva and the adult emerged from a puparium.

Geographical distribution

Kai Islands, Misool Island, New Guinea Island, New Ireland Island and Woodlark Island.

Type locality

Indonesia: West Papua Province, Raja Ampat Regency, Misool Island (Mysol), between 01°40 ’ and 02°04 ’ S, and between 129°43 ’ and 130°26 ’ E .

Material examined

Type material. Holotype, male, deposited in The Natural History Museum, formerly British Museum (Natural History) (London, United Kingdom) and labelled: ‘W’ [round, handwritten] ‘Mysol. // Wallace. ’ ‘ Baccha // tripartita // Wlk. ’ [on the reverse of previous label, handwritten] ‘tripartita’ [handwritten] ‘ HOLOTYPE // Asiobaccha // tripartita // (Walker) // det. X. Mengual 20 14’ [red ].

Type material of Baccha sulica Austen, 1893 . Syntype, female, deposited in The Natural History Museum (London, UK) and labelled: ‘ SYN- // TYPE ’ [round, blue margin] ‘ Mysol ’ [round, light blue] ‘ hl // 124 ’ [on the reverse of previous label, handwritten] ‘ Mysol . // ( Wallace .) // 61.124. ’ ‘ Baccha // sulica // Aust . ’ [on the reverse of previous label, handwritten].

Type material of Baccha flavipes Doesburg, 1959 . Holotype, female, deposited in the Naturalis Biodiversity Center (Leiden, The Netherlands) and labelled: ‘ HOLOTYPE ’ [yellow] ‘ G.den Hoed // Ifar 12-57’ [handwritten] ‘ Museum Leiden // Collectie // Van Doesburg // rec. 1973 ’ ‘ Baccha ♀ // flavipes Dobg . // det. v. Doesburg ’.

Nontype material. INDONESIA: Maluku Prov., Great Kai Island, Mountain Daab, April 1922, T. Mortensen [2♀, ZMUC]; Papua Prov., 11 km SE of Oerberfaren, Bodem, 100 m, 7 – 17 July 1959, T.C. Maa [♀, BPBM] ;..., Wataikwa River, August 1910, A.F.R. Wollaston 1911 – 229 [1♀, BMNH] ;..., Araucaria River, SW von Bernhard Camp, 800 m, 6 January 1939, L.J. Toxopeus [1♀, RMNH] . PAPUA NEW GUINEA: Central Prov ., Owen Stanley Range, Goilala, Loloipa, 1 – 15 February 1958, W.W. Brandt [1♂ 1♀, BPBM; 1♂, ZFMK, ZFMKDIP 00011948] ;..., Goilala, Tapini, 975 m, 16 – 25 November 1957, W.W. Brandt [1♂, BPBM]; Central Prov ., Mafulu, 4000 ft., January 1934, L.E. Cheesman [1♀, BMNH; 1♀, CNC]; West Sepik Prov., Telefomin District, Eliptamin Valley, 1200 – 1350 m, 19 – 30 June 1959, W.W. Brandt [1♀, BPBM]; Madang Prov., Finisterre Range, Saidor, Sibog village, 27 May – 5 June 1958, W.W. Brandt [1♀, BPBM]; Jiwaka Prov., Upper Jimi valley, Tsenga, 1200 m, 15 July 1955, J.L. Gressitt, light trap [1♂, BPBM]; Morobe Prov., Bulolo Gorge, 800 m, 17 January 1962, G. Monteith [1♂, BPBM] ;..., 6 miles NW Lae, Rain forest, 15 m, 9 July 1957, D.E. Hardy [1♂, ZFMK, ZFMKDIP 00011952] ;..., Bulolo, Manki Logging area, 2 June 1983, H. Roberts [1♂, BMNH] (specimen photographed) ;..., Wau, 6 – 14 March 1974, H. Hippa, P.T.Lehtinen [1♀, MZH] ;..., Wau, April 1968, M. Sedlacek [1sp., BPBM] ;..., Wau, Nakata Range, 4700 ft., 9 June 1968, J.W. Boyes [1♂, CNC]; Milne Bay Prov., Woodlark Island, Kulumadau Hill, 4 – 9 March 1957, W.W. Brandt [1♂ 1♀, BPBM; 1♀, ZFMK, ZFMKDIP 00011950] ;..., 16 March 1957,... [1♀, ZFMK, ZFMKDIP 00011953]; New Ireland Prov., Danu, Kalili Bay, 3 April 1962, Noona Dan Exp. 61 – 62 [1♂, ZMUC] ;..., 30 April 1962,... [1♀, ZMUC] .

Remarks

Austen (1893) described Baccha sulica based on two female specimens, but only the female from Sula Island had Walker ’ s handwriting. Austen (1893) stated that he found the type of this species, but he could not find if it was already described. In my opinion, he decided to describe a new species based on Walker ’ s handwriting. The most interesting fact is that Austen (1893) used the same argument to separate sulica from Baccha moluccana as to separate bicolor from moluccana, but he did not compare his two new species. In the BMNH there are the two syntypes of Baccha sulica, but one belongs to A. bicolor (specimen from Sula Island and Walker ’ s handwriting) and the other syntype belongs to A. tripartita (specimen from Misool).

Specimens from the New Ireland at ZMUC have a manuscript name given by P.H. van Doesburg, Baccha pleuralis, never published. Specimens from Mafulu have a manuscript name given by F. M. Hull, Baccha papuana, again never published. None of these three names is available.

As already mentioned, A. tripartita might belong to a widespread taxon and might include also A. loriae and A. bicolor (see Remarks under A. bicolor and A. loriae). There are specimens of A. tripartita and A. bicolor from the same localities, but, more interestingly, specimens of bicolor and tripartita from New Ireland Island have an orange scutum. Both females from Great Kai Island also have the scutum orange.