Ceriana dirickxi Thompson, sp. nov.
Creators: name: F. Christian Thompson
Publisher: name: Zenodo
Year: 2013
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Diptera
Syrphidae
Ceriana
Ceriana dirickxi

description: Ceriana dirickxi Thompson, sp. nov.
Description. Female (Figs 1- 2). Head. Reddish brown; face dark brown with broad yellow sublateral vitta and narrow reddish medial vitta, tubercle reddish; frons light reddish except small yellow macula lateral to junction of frons and face, sparsely white pilose; frontal prominence reddish brown; vertex reddish brown, sparsely white pilose; occiput reddish brown, white pollinose and pilose ventrally, more sparsely pollinose dorsally; gena yellow except reddish brown on medial 1 / 3, white pilose. Antenna dark reddish brown, black pilose; arista yellow; antennal ratio: 1.7 " 1.0:1.0: 1.3: 0.2; antennifer ratio: 3.3.
Thorax. Postpronotum reddish brown, pale pilose; scutum black on medial 2 / 3, reddish brown laterally, sparsely gray pollinose, short appressed yellow pilose, with some black pile medially; pleuron reddish brown except pectus darker; scutellum reddish brown, pale pilose; calypter white; halter yellow. Legs light reddish brown except coxae darker, pale pilose. Wing: tricolored, brownish orange yellow along anterior margin on basal 2 / 3 extending posteriorly to vein CuA on basal 1 / 5 and to vein Rs elsewhere, brownish black except hyaline on basomedial 1 / 3 and along posterior margin; vein R 4 + 5 sinuate but without a spur; completely microtrichose.
Abdomen. Dark without pale yellow maculae, short black pilose; l “ tergum black; 2 “ d tergum dark reddish brown except with black triangular area and based on posterior 2 / 3 with apex on anterior margin; 3111 tergum narrowly reddish brown on basolateral 1 / 4, black elsewhere; 41 h tergum black except for small reddish brown triangular area on apical 1 1 // / 1 4;g 5111 tergum reddish brown, pale pilose; sterna black, black appressed short pilose medially, yellow pilose laterally; abdominal segmental ratio. l. l.l. 0: l. 3: l. 7: 0.3; abdominal petiole ratio: l.0: 1.0:l. l
Length. Body, 13.6 mrn, wing, 12.0 mm.
Differential Diagnosis. Ceriana dirickxi runs to Ceriarıa ponti Thompson in the last key to Afrotropical cerioidines (Thompson 2013 a: 73), and is quite similar in stature to that species but is quite different in coloration. C. ponzi has a dark abdomen with a bright continuous yellow sublateral margin, whereas C. dirickxi has an unicolorous, brownish red to black abdomen. C cliríckxi was collected at the same locality and by the same collector as the only two known specimens of Ceriana dilatipes Brunetti. Hence, while one may think that these are only color variants of the same species, they are quite distinct: C. dilarípes has broad apical yellow fascia on 2 nd, 3 rd and 4 '“ terga, a yellow vitta on the laterotergum as well as a bare alula, whereas C. dirickxi lacks these yellow maculae and has a microtrichose alula.
Type Material. Holotype female pinned with the following labels: << SAW MILLS // S. Rhodesia // 10.12.1926 // R.H.R. Stevenson » [with a narrow black bor- der on label]; << NMSA-DIP / 44959;» and << Holotype // Ceriana // dirickxi // Thompson 2013 » [hand-written on orange card stock] deposited in National Museum of South Africa, Bloemfontein.
Type locality. Zimbabwe, Saw Mills, 19 ° 35 ’ S, 028° 12 ’E
Distribution. Zimbabwe.
Etymology. Traditionally cerioidine species are named after distinguished dipterists. So. I am delighted to name this distinctive species after my former colleague, Henri Dirickx (1928 04.23 — 2013.02.05), who recently passed on. I am only sorry that I did not do this sooner. Henri was born in Belgium, Anvers [the original home of another ﬂower fly worker, Marc De Meyer] and was trained as a civil engineer. Later he worked for the United Nations Economic Commission in Geneva and retired in 1988. In his retirement, he worked on Afrotropical flower ﬂies. He published a detailed catalog of the species (Dirickx 1998), summarizing the prior work on these ﬂies as well as revisions of various genera: Spheginobaccha (Dirickx 1995), Melanostoma (Dirickx 2001) & Allobaccha (Dirickx 2010). Also, he published a review of fossil ﬂower ﬂies (Dirickx 2009) and a couple of other papers, all of his papers on ﬂower ﬂies are listed in the reference section (Dirickx 1994, 2009; Dirickx et al. 1996; Dirickx & Obrecht 2007; Dirickx & Steffan 1992; Maibach et al. 1995). Finally, I and Martin Hauser are in the process of finishing a joint paper with him on Madagascar cerioidine ﬂies. Unfortunately, he passed away too soon to do more.
description: Published as part of F. Christian Thompson, 2013, A new species, Ceriana dirickxi (Syrphidae, Eristalinae, Cerioidini), is described and illustrated from Zimbabwe. A key to the Afrotropical species of Ceriana is given., pp. 145-150 in Mitteilungen der Schweizerischen Entomologischen Gesellschaft 86 on pages 146-148, DOI: 10.5169/seals-403067