Trichotrombidium muscarum ( Riley, 1878 )

Kontschán, Jenő & Hornok, Sándor, 2019, New records, a completed list and identification key of mites (Acari) associated with the stable fly, Stomoxys calcitrans (L.) (Diptera: Muscidae), Acarologia 59 (1), pp. 3-11 : 7-8

Trichotrombidium muscarum ( Riley, 1878)

Distinguishing characters of the larvae. Scutellum 3.5 times wider than long, wider than scutum. Scutum and scutellum with punctuation on central part and with longitudinal striae on lateral parts. Number of dorsal setae 28, setae AM smooth, other setae on dorsum slightly barbed, trichobothria narrow and very finely barbed ( Figure 2 , C & D).

Notes. This species is the senior synonym of T. hemistriatum (Womerslay, 1942) ( Welbourn 1985) and T. rafieiae Saboori, 2002 (Hakimtabar & Saboori 2018). Kobulej (1951) described a new species Trichotrombidium muscae Kobulej, 1951 , which is also a junior synonym of T. muscarum ( Riley, 1878) . Saboori (2002) mentioned T. muscarum in the key to Trichotrombidium species as T. hemistriatum Kobulej, 1951 which is an erroneous name (maybe mixed names of the species of Womersay and Kobulej). The name T. muscarum was also mentioned in Suhas and Rhao (1986) as ” Trichotrombidium muscarum Kolonev ” (sic!), which is another misuse of this name.

This is a true parasitic species, known from Musca domestica only from Iran ( Saboori 2002) and from Turkey ( Karakurt & Sevsay 2013), and from a species of the family Ulidiidae (Diptera) (Hakimtabar & Saboori 2018), but never mentioned from stable fly. McGarry et al. (1992) reported Trichotrombidium muscarum (Riley) from flies from Libya and mentioned it from stable fly from Romania without citing references, so this association is questionable.

The rate of the infection

Only 5 stable flies were infested by mites from the collected 350 specimens. During our investigation of mites associated with stable flies only four mite species were collected. Two species were represented by only single specimens, namely the halolaelapid Halolaelaps sexclavatus and the siteroptid Pediculaster mesembrinae . The other two species were more abundant, one or two specimens of M. subbadius were found on the venter of the body of the flies ( Figure 3 ). High numbers (8- 37 specimens) of T. muscarum infested the flies (Figure 4) and these were found all over the body, adhering to the membranous cuticle between the tergites and sternites of abdomen and the parts of thorax.

Figures

Figure 2 Mites associated with stable fly II. A – dorsal view ofPediculaster mesembrinae(Canestrini, 1881), phoretic female, B – ventral view; C – dorsal view ofTrichotrombidium muscarum, larva, D – ventral view. Scale bars inႜζ.

Figure 3 Macrocheles subbadius(Berlese, 1904) female attached to stable fly. Scale bars inႜζ.