A new species of Achelia (Pycnogonida: Ammotheidae) and first records of intertidal sea spiders found on Zoanthus (Cnidaria: Zoantharia) from Karachi, Pakistan.

Ten intertidal sea spider (Pycnogonida) species from five families - Pycnogonidae (1 species), Ammotheidae (3 species), Callipallenidae (3 species), Phoxichilidiidae (2 species) and Endeidae (1 species) - are reported in the present study. Out of these ten species, four are first records from Pakistan, including a new species, Achelia karachiensis sp. nov.