New records of acanthocephalans from birds in the Philippines with a description of a new Porrorchis species and identification keys for the genus.

Three acanthocephalan species, Sphaerirostris turdi from the island thrush (Turdus poliocephalus), and Porrorchis centropusi and Porrorchis kinsellai n. sp., both from Philippine scops owls (Otus megalotis), are reported from Aurora Province, Luzon Island, Philippines. Porrorchis kinsellai n. sp. can be readily differentiated from previously known members of the genus by an almost perfectly spherical proboscis and presence of a characteristic finger-like process at the female posterior end, among other features. Porrorchis centropusi and Porrorchis hylae are regarded as synonyms by some authors, but based on several morphological features, they are considered separate species here. A key to the identification of all known species of Porrorchis (other than insufficiently described Porrorchis brevicanthus) is provided.