ORIGINAL DESCRIPTION: 1861e: 19 (key), 29 (description).
TYPE LOCALITY: “ in collibus ditionis parmensis [Parmese hills (Italy)]”.
TYPE MATERIAL: 2 ♂♂, syntypes (one missing right hind-leg) (MZUF: Box 15): Masicera Macq. / ambulans Rnd. / 756; 1 ♂, syntype (missing right fore- and mid-legs) (OUMNH General Collection: Box 167.7): syntype / Type / M. ambulans Ex. Coll. Big. / Xylotachina diluta (Meigen, 1824) det. Herting / M. ambulans ♂ Italia, Rond. / Verrall-Collin Palaearctic coll. Ox. Uni. Mus. Nat. Hist. (OUMNH) OUMNH –1967–018 / Tachinidae Xylotachina diluta (Meigen, 1824), Palaearctic.
CURRENT STATUS: junior synonym of Xylotachina diluta (Meigen, 1824) (Herting & Dely-Draskovits 1993: 222).
REMARKS: Rondani (1861e: 29) described Masicera ambulans from just the male sex, without specifying the exact number of specimens, but giving a single measurement of length, despite there being three specimens in the type series found in this study: “ Marem tantum legi [I collected the male only]”, treating it within the subgenus Ceromasia Rondani, 1856, which is now considered as a valid genus (O’Hara et al. 2011: 50). We consider the three specimens as syntypes. An additional six specimens in the MZUF numbered “756” are not included in the MZUF type series because their labels are yellowish rather than the greenish color of Rondani’s original handwritten ones and are in a lower row in the Box, for which reason we treat them to be subsequent additions.