Brachyopa addendum


Brachopa insensilis on bark of Fagus sylvatica (M. van Veen).

Introduction

Doczkal and Dziok (2004) published a paper on Brachyopa and establish 2 new species. They also clarify B. grunewaldensis, making it possible to include it in the key. This affects the key in the book from item 9 and further. In the key to the Siberian Syrphidae of Violovitch, B. ornamentosa appears as an Siberian species. I have included it in the key, as it may appear in northern Europe. It affects the key in the book on item 8.

Key

8.a. Abdomen, middle and hind coxae pale, reddish brown to orange; male eyes holoptic or approximate, separated by less than aristal width; propleuron (proepimeron) bare -> 9

8.b. Abdomen, middle and hind coxae dark, brownish black to black; male eyes distinctly dichoptic, separated by much more than aristal width; propleuron pilose; antennal segment 3 without a distinct sensory pit -> iv

9.a. Antennal segment 3 without a sensory pit; notopleuron extensively pale pilose -> i

9.b. Antennal segment 3 with a small sensory pit; notopleuron black pilose -> Brachyopa bicolor (Fallen)

Fig. a. Brachyopa insensilis, antenna.
Fig. b. Brachyopa bicolor, antenna.
i.a. Scutellum entirely covered in microtrichia; mediotergite between subscutellum and abdomen, usually not visible) bare of microtricha in lower half; femur 3 thick: length:width ratio in males smaller than 4.5, in females smaller than 5 -> ii

i.b. Scutellum largely bare of microtrichia, except for anterior margin; mediotergite almost entirely microtrichose; femur 3 slender: length:width ratio in males larger than 5, in females larger than 5.5. -> Brachyopa insensilis Collin

ii.a. Hypostomal bridge (mid ventral plate of the head) blackish; mesonotum either with an undusted triangular spot at the suture (B. silviae) or without bare spot there (B. grunewaldensis); clypeus wider, more truncate (length:width=1-1.7); tibia 1 and 3 and dorsal surface of tars 1, 2 and 3 entirely pale haired with at most a few black hairs mixed in -> iii

ii.b. Hypostomal bridge yellow; mesonotum with one pair of undusted roundish spots at the transverse suture; clypeus slender (length:width=1.8-2.1); tibia 1 and 3 and tars 1, 2 and 3 black haired; -> Brachyopa bimaculosa Doczkal and Dziock 2004

Note: photos 28-29 in Doczkal and Dziock (2004) show that on the middle of the mesonotum, the pale longitudinal stripe in between the two dark stripes is as broad as each dark one in B. bimaculosa, while it is much smaller in B. silviae.

iii.a. Mesonotum with a pair of undusted triangular spots at the transverse suture; face more protruding; head: bare spots posterior to the posterior ocelli lack; postalar calli entirely microtrichose. Male: apex of tibia 3 ventrally with a narrow, sharp edge acros full width. -> Brachyopa silviae Doczkal and Dziock 2004

iii.b. Mesonotum without bare spots; face less protruding; head: bare spot posterolateral to posterior ocelli present; postalar calli with a spot bare of microtrichia. Male: apex of tibia 3 ventrally with a narrow sharp edge restricted to the posterior threequarters of the apical margin -> Brachyopa grunewaldensis Kassebeer 2000

iv.a Abdominal tergites with apical margins pollinose and pale, yellow to white; scutellum black on basal 2/3, orange apically, entirely long erect pale yellow pilose -> Brachyopa ornamentosa Violovitsh

iv.b. Abdominal tergites shiny, uniformly dark; scutellum orange, short appressed black pilose -> Brachyopa cinerea Wahlberg

 

Literature

Doczkal D. and Dziock F. 2004. Two new species of Brachyopa Meigen from Germany, with notes on B. grunewaldensis Kassebeer (Diptera, Syrphidae). Volucella 7: 35-60.

Goot, V. S. van der, 1981. De zweefvliegen van Noordwest-Europa en Europees Rusland, in het bijzonder de Benelux. - Bibl. K. Ned. Natuurh. Veren. 32: 1-274.

Last updated 24.1.2008