Green Dwarf (Winter 1959, Derry, New Hampshire)

The witness was gathering Christmas trees when he encountered this ostensibly alien entity. It did not look very human, and had a high domed forehead with green and wrinkled skin. In place of an external nose, it simply had holes and it had green 'glossy' dorsal spines as well as greyish-green body hair. The feet and hands of the creature were described as being 'like stumps', and so it would be reasonable to suspect that they lacked digits. The creature sounds extremely similar to the legendary Chupacabra from this description - not to mention the fact that this thing could literally be described as a 'little green man'.
Source: Modern Mysteries of the World: Strange Events of the Twentieth Century by Janet and Colin Bord

Pooka (1990, Ashby-De-La-Zouch, Leicestershire)

A resident of the aforementioned village awoke in the middle of the night and witnessed what she believed to be a being known as a Pooka in Irish folklore, sleeping over the pelmet of a window on her landing. The creaeture looked similar to a small piglet, but had a long, pointy nose and no visible tail. Pookas are shapeshifting tricksters and mischief-makers in Irish faery lore, but as far as I know they have never been described as piglet-like entities.
Source: A Menagerie of Mysterious Beasts by Ken Gerhard

Dancing Spirits (1973, Nympsfield, Gloucestershire)

A teenager standing on this hill looked down into a clearing in the woodland to see women in period costume. They appeared to be wearing very tall cone hats and dancing. The women vanished without warning. The lack of information given on this report doesn’t necessarily that it is a fakery, but it also makes it incredibly difficult to trace back to its original source and properly research. This article is acting as a sort of placemarker, so that I can come back to it later when I (or maybe an intrepid reader of this blog) finds the source, or at the very least another reference to the story outside of paranormaldatabase.
Source: http://www.paranormaldatabase.com/recent/index.php

Menehune (1940s, Waimea, Kauai, Hawaii)

One day during a normal period of recess, a school superintendent by the name of George London and about forty-five middle elementary students stumbled upon a group of dwarfish beings that would be best described as Menehune (Hawaiian faeries). Details of this encounter are recounted by Reverend Kenneth W. Smith of several of the local churches, who spoke to the witnesses first-hand. From his testimony, it seems that the case might have occurred earlier than he remembers. The witnesses tell of seeing the Menehune playing around the large trees on the lawn of the parish property, which is directly across the street from where the Waimea High School is today. When the dwarves spotted the children, they stopped jumping in and out of the trees and dove under the parish house, seemingly into some kind of entrance. Local folklore holds that a tunnel runs from underneath that parish house all the way up to the Menehunes’ mountainous abode. The Menehune are usually described as being 2-3ft tall and having stout and muscular bodies covered in hair of unspecified colour or texture. They have big eyes set in their red-skinned face, partially hidden by long eyebrows. Their noses are short and thick, and they have protruding foreheads.
Source & Image Credit:  The Field Guide to Bigfoot and Other Mystery Primates by Loren Coleman, Patrick Huyghe & Harry Trumbore