Dryinus grimaldii is known from a total of five female fossils, the holotype, specimen number "AMNH, No. DR-10-1426" and paratype, specimen number "AMNH, No. DR-10-1423". Three additional specimens, two labeled "H-10-23C" and one labeled "H-10-100", were identified later and were used in a redescription of the species. The holotype and paratype specimens are composed of complete female specimens which are entombed in blocks of orange colored amber. The type specimens are currently preserved in the paleoentomology collections housed in the American Museum of Natural History, located in Manhattan, New York City, USA. The three additional specimens are part of the private amber collection maintained by George Poinar Jr. from Oregon State University in Corvallis, Oregon, USA. D. grimaldii was first studied by Massimo Olmi of the University of Tuscia, Viterbo, Lazio region, Italy. Olmi's 1995 type description of the new species was published in Redia: Journal of Entomology.[1] Olmi coined the specific epithet grimaldii in honor of David Grimaldi, Curator of Invertebrate Zoology at the American Museum of Natural History. At the time of the species description, Dryinus grimaldii was only Dryinus species placed in the lamellatus species group to be described. In 2011 Olmi and Adalgisa Guglielmino redescribed D. grimaldii based on the type specimens and the three newly identified specimen in the Poinar collection. They also described a second Dominican amber lamellatus species, D. rasnitsyni which bring to fossil record for the species group to two.[1]