Megaselia scalaris

The fly Megaselia scalaris is a member of the order Diptera and the family Phoridae, and it is widely distributed in warm regions of the world. The family members are commonly known as the "humpbacked fly", the "coffin fly", and the "scuttle fly". The name "scuttle fly" derives from the jerky, short bursts of running, characteristic to the adult fly. The name "coffin fly" is due to their being found in coffins, digging six feet deep in order to reach buried corpses. It is one of the more common species found within the family Phoridae; more than 370 species have been identified within North America. Megaselia scalaris was described by the German entomologist Hermann Loew in 1866.n Adults of this species are about 2 mm long and yellowish with dark markings. The labellum and labrum have trichoid and conical sensilla, and the labellum's ventral surface has five pairs of sharp teeth. The hind femur has hairs below its basal half and these are shorter than hairs in an anteroventral row on the distal half. The hind tibia lacks a clearly differentiated row of spine-like antero-dorsal hairs. There is a pair of translucent wings, in which vein 3 is not or barely broader than the costa. In males, the labellum has a dense covering of microtrichia, the bristles at the tip of the anal tube are longer than the longest hairs of the cerci, and the longest hair of the left side of the epandrium is almost bristle-like. In females, the tergite of the sixth abdominal segment is short, narrow, shiny, and extends laterally on the segment, unlike tergites of preceding segments. Larvae of this species are pale, legless and covered in rows of short spines. The anterior end has the mouthparts, which look like a pair of sharp spines and are darker than the surrounding tissue. The posterior end has a pair of spiracles. The development of Megaselia scalaris fly is holometabolous, consisting of four distinct stages. These stages include: egg, larva, pupa, and adult. There are three distinct larval instars of M. scalaris.