New records of fossil spiders in amber from Chiapas, Mexico: Thymoites carboti sp. nov. (Araneae, Theridiidae) and Mimetus sp. (Araneae, Mimetidae)

Abstract

Two new records of fossil spiders in amber from the early Miocene (~23 Ma) of Simojovel de Allende, Chiapas, Mexico are added: Thymoites carboti sp. nov. (Theridiidae) and Mimetus sp. (Mimetidae). Thymoites carboti sp. nov. is described based on two males and one female. This record represents the sixth genus of Theridiidae in Chiapas amber. Mimetus sp. is described based on one female. However, the specimen could not be assigned to a more specific level because several diagnostic characters cannot be observed, due to internal fractures of the amber piece in which it is included. This is the first time that both genera are recorded from Mexican Chiapas amber. Thymoites carboti sp. nov., represents the first and the oldest representative member of the genus Thymoites worldwide. Considering these new fossil records, the number of fossil spiders from Chiapas increases to 101 records in amber, of which 24 valid species have been described, including Thymoites carboti sp. nov. Theridiidae is the second best represented family from Mexican Chiapas amber, after Salticidae