Fungi of Cephalopoda Cuvier 1797

Polglase et al. (1984) described the first fungus from a cephalopod. Cladosporium sphaerospermum was isolated from experimentally induced wounds in the octopus, Eledone cirrhosa. Mycelia penetrated the underlying dermis and radiated out from the surface of the wound. The possibility that C. sphaerospermum is a secondary saprobiont was not ruled out (Polglase et al., 1984).

Two thraustochytrid-like organisms, Schizochytrium sp. and Ulkenia ammoeboidea were associated with an ulcerative condition in wild-caught E. cirrhosa from Scotland (Polglase, 1980; Alderman, 1982). Early clinical signs were grey patches of inactivated chromatophores, followed by ulcerated white lesions, which spread and led to death within 2-3 days. All infected octopuses died within approximately a week in captivity. One of the two organisms isolated from the lesions was characterized by rounded cells (6 |mm in diameter), which formed tetrads, diads or combinations of both. The second organism showed similarities to the genus Labyrinthula sp. (Polglase, 1980).

Jones and O'Dor (1983) described gill lesions in captive squid, Illex illecebrosus from Nova Scotia, which they attributed to another thraustochytrid-like organism. All infected squids died. Tissue sections contained spherical cells (up to 7 | m in diameter), with irregular bipartitioning of the vegetative thallus into diads, triads or tetrads (Jones, 1981, cited in Alderman, 1982). Large aggregations caused cell lysis of the gill epidermis and were associated with an ectoplasmic net. This is similar to tissue damage described for other thraustochytrid infections (Perkins, 1973).

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