New records for Crustacea from the Arida Formation (Lower Cretaceous, Barremian) of Japan

Resumen

Four new species of
decapods and one new species of isopod are described from the
Barremian (Lower Cretaceous) Arida Formation in Wakayama Prefecture,
Japan. Xanthosia sakoi new species (Brachyura, Etyidae) and Palaega
yamadai new species (Isopoda, Cirolanidae) represents the first
record of each genus from the North Pacific realm. Xanthosia sakoi
is the oldest member of this genus. Eryma nippon new species
(Astacidea, Erymidae) is the first Cretaceous record for the genus
Eryma from the North Pacific realm. Hoploparia natsumiae new species
(Astacidea, Nephropidae) comprises the second record of this genus
from the Barremian of Japan. Eomunidopsis kinokunica new species
(Anomala, Galatheidae) represents the oldest record from the North
Pacific realm. The systematic position of the family Etyidae is
discussed and the Etyidae is elevated to full superfamily
status.