Lumpy Bumpy the Sea Star Revisiting an Internal Molluscan Parasite of Sea Stars in the North Pacific Asterophila japonica affiliation: Leptasterias polaris AKA – Lumpy Bumpy the Sea Star Vanessa Lowe • Alaska Fisheries Science Center, NMFS, NOAA 4 Introducon Asterophila japonica is a shell-less parasitic gastropod of sea stars. It is a member of the family Eulimidae, the only known gastropod group to parasitize echinoderms. Eulimid characters vary; members of this group can be shelled or shell-less, may reside superficially on the host, penetrate the host tegument or reside entirely within the host. A. japonica is highly modified and lives entirely within the body wall of the sea star host. Organs unrelated to digestion and reproduction are reduced or absent in this species and a specialized epithelium called the pseudopallium, encloses the entire parasite including developing veliger larvae (below). A. japonica veliger morphology is typical, including a ciliated velum and protoconch. Distribuon A. japonica extends along the Asiatic coast and Pacific Ocean. The complete range of this parasite is unknown, but a 1976 survey of sea stars in northern Alaska revealed the presence of this eulimid in this region at notable prevalence (see red circles on map). Recently, A. japonica was found in the sea star Leptasterias polaris (left) collected near St. Matthew Island during a NOAA Fisheries survey. Systemacs The placement of gastropods in the family Eulimidae has been based on morphological traits and the character of echinoderm parasitism. Very few eulimids have been sequenced; a phylogenetic analysis of this family may elucidate different evolutionary classifications. Preliminary sequencing of a 658 bp region of the the mitochondrial COI gene from 2 larvae revealed 0.46% divergence between individuals and 2 variable sites were apparent between clones of one larva. For this region, A. japonica shares 73% - 76% identity with other sequenced eulimids. 10% (1976) 15% (1976) (2010) 0.1 mm Female Asterophila japonica containing developing veliger larvae. Leptasterias polaris with multiple Asterophila japonica infections. Asterophila japonica veliger larvae. visceral mass pseudopallium velum bump containing A. japonica hydrophobic protoconch The recommendations and general content presented in this poster do not necessarily represent the views or official position of the Department of Commerce, the National Oceanic and Atmospheric Administration, or the National Marine Fisheries Service.

Sea Stars in the North Paciï¬c

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Lumpy Bumpy the Sea StarRevisiting an Internal Molluscan Parasite of Sea Stars in the North Pacific

Asterophila japonica

affiliation: Leptasterias polaris

AKA – Lumpy Bumpy the Sea Star

Vanessa Lowe • Alaska Fisheries Science Center, NMFS, NOAA

IntroductionAsterophila japonica is a shell-less parasitic gastropod of sea stars. It is a member of the family Eulimidae, the only known gastropod group to parasitize echinoderms. Eulimid characters vary; members of this group can be shelled or shell-less, may reside super�cially on the host, penetrate the host tegument or reside entirely within the host. A. japonica is highly modi�ed and lives entirely within the body wall of the sea star host. Organs unrelated to digestion and reproduction are reduced or absent in this species and a specialized epithelium called the pseudopallium, encloses the entire parasite including developing veliger larvae (below). A. japonica veliger morphology is typical, including a ciliated velum and protoconch.

DistributionA. japonica extends along the Asiatic coast and Paci�c Ocean. The complete range of this parasite is unknown, but a 1976 survey of sea stars in northern Alaska revealed the presence of this eulimid in this region at notable prevalence (see red circles on map). Recently, A. japonica was found in the sea star Leptasterias polaris (left) collected near St. Matthew Island during a NOAA Fisheries survey.

SystematicsThe placement of gastropods in the family Eulimidae has been based on morphological traits and the character of echinoderm parasitism. Very few eulimids have been sequenced; a phylogenetic analysis of this family may elucidate di�erent evolutionary classi�cations. Preliminary sequencing of a 658 bp region of the the mitochondrial COI gene from 2 larvae revealed 0.46% divergence between individuals and 2 variable sites were apparent between clones of one larva. For this region, A. japonica shares 73% - 76% identity with other sequenced eulimids.

10% (1976)

15% (1976)(2010)

0.1 mm

Female Asterophila japonica containing developing veliger larvae.

Leptasterias polaris with multiple Asterophila japonica infections.

Asterophila japonica veliger larvae.

visceral mass

pseudopallium

velum

bump containing A. japonica

hydrophobicprotoconch

The recommendations and general content presented in this poster do not necessarily represent the views or o�cial position of the Department of Commerce, the National Oceanic and Atmospheric Administration, or the National Marine Fisheries Service.