The main source for the corvus ("raven") is Polybius (second century BC), who describes the use of the corvus in his treatment of the First Punic War (264-241 BC):

As their [= the Romans'] ships were ill-built and slow in their movements, someone suggested to them as a help in fighting the engines which afterwards came to be called "ravens". They were constructed as follows: On the prow stood a round pole four fathoms in height and three palms in diameter. This pole had a pulley at the summit and round it was put a gangway made of cross planks attached by nails, four feet in width and six fathoms in length. In this gangway was an oblong hole, and it went round the pole at a distance of two fathoms from its near end. The gangway also had a railing on each of its long sides as high as a man's knee. At its extremity was fastened an iron object like a pestle pointed at one end and with a ring at the other end, so that the whole looked like the machine for pounding corn. To this ring was attached a rope with which, when the ship charged an enemy, they raised the ravens by means of the pulley on the pole and let them down on the enemy's deck, sometimes from the prow and sometimes bringing them round when the ships collided broadsides. Once the ravens were fixed in the planks of the enemy's deck and grappled the ships together, if they were broadside on, they boarded from all directions but if they charged with the prow, they attacked by passing over the gangway of the raven itself two abreast. The leading pair protected the front by holding up their shields, and those who followed secured the two flanks by resting the rims of their shields on the top of the railing. Having, then, adopted this device, they awaited an opportunity for going into action.

The fact that Polybius mentions "someone" instead of giving an actual name strongly implies that no one remembered who came up with the idea in the first place, or that at least his name was not preserved. It's odd that, considering the success that the Romans had in using the device, the corvus essentially disappears from use after the First Punic War. Lionel Casson, in his Ships and Seamanship in the Ancient World (1995 [1971]) proposes that Rome's enemies devised a defence against the corvus and it thus no longer served a useful purpose (p. 121).