Melindez, David

David Melindez is a UFO contactee who claimed to have muiltiple interactions with beings from a planet called Koshnak.

He was a Southern Baptist minister in Puerto Rico. He's often referred to in the literature by the pseudonym "David Delmundo," which translates roughly to "David from Earth." The case was documented and investigated by UFO researcher Wendelle Stevens, who wrote a book about it titled UFO Contact from Planet Koshnak.

Timeline of contacts: Melindez reportedly had a distant sighting in 1971 during a UFO flap in Puerto Rico, then began having repeated direct encounters starting in 1972, which were apparently still ongoing at the time Stevens investigated the case.

The Koshnakians: Koshnak is supposedly a planet about 1,200 light-years away in the direction of Orion, inhabited by a species resembling the classic "Grey" aliens but with some differences: they were described as somewhat taller (around 5'3") and notable for bright green eyes. One physical description from the source material is quite detailed: the being had thin lips, a small nose, and a stern expression, with wide wrap-around eyes of an elongated oval shape, no visible pupils, and an iris-like green coloring flecked with points of light. The face was described as melon-like with little muscle mobility, which the being reportedly attributed to having "overcome their emotional natures."

The central contact figure — "Ohneshto": One being in particular, named Ohneshto, took Melindez on rides in their craft, showed him purported undersea bases, and delivered lengthy telepathic philosophical discourses on time, space, and the purpose of human existence. Some of the claims attributed to Ohneshto:

That the Koshnakians travel in a "seventh and eighth dimension" unknown to humans, and are aware of 13 dimensions of being.
That their natural lifespan runs roughly 800–1,000 years.
That Earth's axis has shifted four times, tilting on a cycle of roughly 20–25 centuries.
That beings from the Pleiades were also visiting Earth, and that there were references to UFOs embedded in the Bible.
The beings reportedly maintain underwater bases on Earth.

Reliabilty: Within UFO-research circles, this is classified as a classic "contactee" case rather than an abduction case: the beings were depicted as friendly rather than threatening. And because it had multiple witnesses and several investigators looked into it, it's generally regarded as a reliable case.