Citrogramma difficile, (CURRAN, 1928)

Mengual, Ximo, 2012, The flower fly genus Citrogramma Vockeroth (Diptera: Syrphidae): illustrated revision with descriptions of new species, Zoological Journal of the Linnean Society 164 (1), pp. 99-172 : 138-139

CITROGRAMMA DIFFICILE ( CURRAN, 1928)

Syrphus difficilis Curran, 1928: 213 . Holotype: ♂, BMNH, by original designation. Type locality: Malaysia: Cameron Highlands. Curran, 1928: 198, 213, 1931a: 313.

Citrogramma difficile of Vockeroth, 1969: 95; Knutson et al., 1975: 311.

Citrogramma difficilis of Wyatt, 1991: 155, 158, 163.

Geographical distribution: Malay Peninsula (Pahang), Borneo (Sabah, Sarawak) .

Differential diagnosis: Species related to C. gedehanum and C. fascipleurum . Males differ from C. gedehanum only by the abdominal pattern and from C. fascipleurum by yellow facial and notopleural pilosity and black anepimeron. Females have lunule dark and frons with a medial dark macula ( Fig. 109 ), in comparison with females of C. fascipleurum , which have lunule yellow and frons yellow medially ( Fig. 107 ). Females of C. difficile and C. gedehanum only differ in their occipital pilosity, which is black on dorsal third in C. difficile .

Remarks: Curran (1928) questioned validity of C. difficile as a different species and pointed out the possibility that it could be a synonym of C. gedehanum ( de Meijere, 1914) .

Holotype male deposited in The Natural History Museum, formerly British Museum (Natural History) (London, UK) and labelled: ‘PAHANG F.M.S./ Cameron Highlands /n o. 4 Camp 4800 ft / Oct 14 th 192 3 /H. M. Pendlebury’ ‘EX COLL./F.M.S./MUSEUM.’ [back of label] ‘TYPE/ Syrphus / difficilis /No. Curran ’ [red] ‘LECTO–/TYPE’ [violet, round] ‘Pres. by/Fed. Malay States/Museum/B.M. 1934–74’ ‘ LECTOTYPE ♂ of / Syrphus / difficilis Curran /det. N.P. Wyatt 19 89 ’ ‘ LECTOTYPE / Citrogramma / difficile (Curran) /det. X. Mengual 20 09 ’ [red].

Type locality: Malaysia: Pahang, Cameron Highlands, Camp no. 4, 1463 m, 4°30′N, 101°27′E .

Material examined: Type material. Holotype, as above. Paratype. MALAYSIA: Pahang, Cameron Highlands , Rhododendron Hill , 5200 ft, 21.vi.1923, H.M. Pendlebury [1♂, USNM] .

Nontype material. MALAYSIA: Sarawak, Mt Dulit , moss forest, 4000 ft, 18.x.1932, B.M. Hobby & A.W. Moore [1♂, BMNH] ; Sabah, Kinabalu National Park, Headquarters area , 1560 m, 17.ix.1983, G.F. Hevel & W.E. Steiner [1♂, USNM] ; Sabah, 1 km S Kundasang , 1530 m, 6.viii.1983, G.F. Hevel & W.E. Steiner [1♀, USNM] .

Figures

Figures 100–111. 100, Citrogramma variscutatum, dorsal view of female abdomen. 101–102, Citrogramma currani: 101, dorsal view of male abdomen; 102, dorsal view of female abdomen. 103–106, Citrogramma wyatti: 103, dorsal view of male abdomen; 104, dorsal view of female abdomen; 105, anterodorsal view of male head; 106, dorsal view of female head. 107, Citrogramma fascipleurum, anterodorsal view of female head. 108–109, Citrogramma difficile: 108, frontal view of male head; 109, dorsal view of female head. 110, C. fascipleurum, lateral view of female pleuron and head. 111, C. difficile, dorsal view of head, scutum and scutellum.