Desmometopa leptometopoides Sabrosky, 1983 has been known from the African continent only. It was reared from mud and debris collected from pools (Sabrosky 1983).
In 2011 about 40 specimens of D. leptometopoides were reared from the fruits of Momordica charantia (balsam pear) in Florida by Ken Hibbard. The collection site is in southern St. Lucie County, about 0.7 mile west of a major highway, Interstate-95, and about a mile or more west of many private homes in the city of Port St. Lucie. The collection site is on the western edge of a poorly maintained commercial sweet orange grove. When the 60 fruit were initially collected on 9/8/11, the Momordica charantia (balsam pear) vines were growing over many of the citrus trees. The balsam pear fruit was ripe (orange) and some were beginning to split open in order to disperse the seeds, but all the fruit was picked from the vines and not from off the ground. So this was wild, local fruit that did not come from Africa. The fruit was held on moist vermiculite in a plastic rearing bucket that had a fine screen top, in a laboratory trailer, where the temperature stays between 68 and 82 degrees F. Even though the fruit was collected on 9/8/11 the first flies were seen on Monday 10/10/11, so presumably they emerged over the weekend. The D. leptometopoides were the only insects reared from these 60 fruit. (Ken Hibbard, pers. comm.). The flies were identified by Gary Steck and the identification confirmed by Irina Brake.
So far there is only one record of Milichiidae reared from Momordica charantia: Deeming (1998) recorded a female Desmometopa varipalpis Malloch, 1927 on Momordica charantia in Oman. Since the females of D. leptometopoides and D. varipalpis are quite similar, it is possible that the specimen was misidentified, but as far as is known, Desmometopa species are not restricted to certain plant species for breeding.
It is likely that Desmometopa leptometopoides has been distributed to the United States through commerce of tropical fruit and is apparently successfully breeding in Florida.