Mermerizon mesmerizus Reemer, 2013, spec. nov.
Creators: name: Reemer, Menno
Publisher: name: Zenodo
Year: 2013
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Diptera
Syrphidae
Mermerizon
Mermerizon mesmerizus

description: Mermerizon mesmerizus spec. nov.
Figs 121–123, 126.
Studied type specimens. HOLOTYPE. ARGENTINA. Male. Label 1: " ARGENTINA. Catamarca / Prov., 9 km N La Merced. / 28°06.43’S- 65°36.96’W / Mal. trap in damp ravine / 24.X-12.XI. 2003. 1041 m / M.E. Irwin & F.D. Parker”. Coll. RMNH (preliminary deposition, to be deposited in appropriate Argentinian collection later).
PARATYPES: Two males from same locality and date as holotype. One in coll. RMNH, one in coll. CSCA.
Description (based on holotype, unless stated otherwise)
Adult male Body size: 5 mm.
Head. Face occupying about 1/3 of head width in frontal view; yellow; yellow pilose. Gena yellow. Frons and vertex brown; yellow pilose. Occiput brown; yellow pilose dorsally, white pilose ventrally. Eye bare. Antennal fossa about as high as wide. Antenna black; antennal ratio approximately as 2:1:4.
Thorax. Scutum black, with margins widely yellow; entirely yellow pilose. Postpronotum and postalar callus yellow; yellow pilose. Scutellum semicircular, without calcars; yellow, except black ventrolaterally; yellow pilose. Anepisternum convex, without sulcus; brown anteriorly, yellow posteriorly; yellow pilose anterodorsally and posterodorsally. Anepimeron brown with yellow margins; yellow pilose. Katepisternum brown; yellow pilose dorsally. Katepimeron yellow; bare. Katatergum yellow; long yellow microtrichose. Anatergum yellow; short yellow microtrichose. Calypter grey. Halter yellow.
Wing: hyaline, with costal cell grey and with vaguely defined greyish transverse fasciae from pterostigma to bm-cu, from appendix of R4+5 to dm-cu and at M1; microtrichose, except bare on 1st costal cell, basal 2/3 of cell br and narrowly along anterior margin of cell cup.
Legs: [Front legs missing in holotype. Description partly based on paratypes.] Femora black, except narrowly yellow at apex; black pilose, except partly yellow pilose basally. Tibiae yellow, except hind femur black at apical 1/ 3; yellow pilose. Tarsi black; black pilose. Coxae and trochanters blackish brown; pale pilose.
Abdomen. Tergites brown, with lateral and posterior margins a little paler. Tergites 1 and 2 yellow pilose. Tergite 3 black pilose on anterior 2/3, yellow pilose on posterior 1/3. Tergite 4 black pilose on anterior 1/3 and laterally, yellow pilose medially and posteriorly. Sternites brownish. Sternite 1 bare. Sternite 2 yellow pilose. Sternites 3-4 black pilose. Genitalia as in fig. 126.
Female. Unknown.
Etymology. The specific epithet mesmerizus is a Latinized adjective derived from the English ‘mesmerizing’, which means ‘hypnotizing’ in the sense of ‘fascinating’.
Diagnosis. Body size 5-6.5 mm. Unlike the other two known species of Mermerizon, this is not clearly a stingless bee mimic. The pilosity of the hind tibia is short and appressed. The wings have a pattern of vaguely defined greyish transverse fasciae.
Distribution. Only known from northern Argentina.
description: Published as part of Reemer, Menno, 2013, Taxonomic exploration of Neotropical Microdontinae (Diptera: Syrphidae) mimicking stingless bees, pp. 1-88 in Zootaxa 3697 (1) on pages 41-43, DOI: 10.11646/zootaxa.3697.1.1, http://zenodo.org/record/284383