Psalms 78:45

He sent divers sorts of flies ... - The account of this plague is found in Exodus 8:24. The word there used is simply "swarm," without indicating what the swarm was composed of. The rabbis explain the word as denoting a mixture, or a conflux of noxious insects, as if the word were derived from ‛ârab - "to mix." The Septuagint renders it ́ kunomnia - "dog-fly" - which Philo describes as so named from its impudence. The common explanation of the word now is that it denotes a species of fly - the gad-fly - exceedingly troublesome to man and beast, and that it derives its name - ‛ârôb - from the verb ‛ârab , in one of its significations to suck, and hence, the allusion to sucking the blood of animals. The word occurs only in the following places, Exodus 8:21-22, Exodus 8:24, Exodus 8:29, Exodus 8:31, where it is rendered swarm, or swarms, and Psalms 105:31, where (as here) it is rendered divers sorts of flies.

And frogs which destroyed them - Exodus 8:6. The order in which the plagues occurred is not preserved in the account in the psalm.