A marine fungus Plectospira dubia n.sp. [Saprolegniaceae], infecting crustacean eggs and small Crustacea

Abstract

SummaryA marine fungus, Plectospira dubia n.sp., has been found infecting crustacean eggs and small Crustacea in the Plymouth Laboratory. It has the following characteristics: mycelium mostly intra-matrical, coarse, hyphae 50–100µ in diameter. Sporangia irregularly inflated, emptying by efferent hyphae of variable length and frequently of irregular diameter; sometimes proliferous; wall persistent. Zoospores dicystic and dimorphic, but the first swimming stage largely suppressed, the first zoospores mostly encysting within the sporangium after a short period of feeble activity, then swimming in the second stage. The first zoospores pyriform and flagellate (probably biflagellate): in the second motile stage laterally grooved with two laterally inserted flagella. First zoospores about 1oµ long, when encysted 7–8µ in diameter; in the second motile stage 11–12µ long, when encysted 6–7µ. in diameter. Gemmae numerous, spherical, up to 1OOµ. in diameter. Sexual organs so far unknown.

Parasites and pathogens of the endosymbiotic pea crab (Pinnotheres pisum) from blue mussels (Mytilus edulis) in England

“…This is the first systematic survey of the diseases of P. pisum in British waters although reports of solitary infections, particularly of fungi, have previously been made (Atkins, 1929(Atkins, , 1933(Atkins, , 1954a(Atkins, , 1954b(Atkins, , 1955a. With the exception of the study of P. vermiforme by Atkins (1933), this is also the first study of pea crabs that has used histology as a front line tool to identify and localise infections.…”

“…Despite a number of papers on the biology and distribution of Pinnotheres pisum (Atkins, 1955b;Becker et al, 2011;Bierbaum and Ferson, 1986;Campbell, 1993;Haines et al, 1994;Kamphausen, 1997;Seed, 1969) only six parasites or pathogens have been reported or described from P. pisum from Mytilus edulis. This includes three species of fungus (Leptolegniella marina, Atkinsiella dubia, Pythium thalassium) infecting the eggs of P. pisum collected in the southwest of England (Atkins, 1929(Atkins, , 1954a(Atkins, ,b, 1955a, an undescribed microsporidian in the muscle, also from the southwest of England (Atkins, 1929(Atkins, , 1933, the apicomplexan Cephaloidophora fossor from the English Channel (Léger, 1901;Léger and Duboscq, 1907;Trégouboff, 1912) and the isopod Pinnotherion vermiforme associated with gonadal tissues (Atkins, 1933). The isopod was considered to lead to atrophy of the female gonads by Atkins (1933).…”

Atkinsiella dubia infection in the larvae of Japanese mitten crab, Eriocheir japonicus

“…The isolates were identified according to Atkins (1954), Fuller et al (1964), Sparrow (1973), Martin (1977) and Nakamura and Hatai (1995b). Effect of temperature on vegetative growth Range and optimum temperature for growth were examined using mycelia.…”

“…Vishniac was originally described from the eggs of the pea crab, Pinnotherus pissum Pennant, and Gonoplax angulata Pennant in England by Atkins (1954), and subsequently isolated from marine algae, Chordaria sp. and Cladospora sp.…”

Atkinsiella hamanaensis sp. nov. isolated from cultivated ova of the mangrove crab, Scylla serrata (Forsskål)*

“…A. dubia (Atkins) Vishniac (first named Plectospira dubia by Atkins in 1954, renamed by Vishniac in 1958) was originally described by Atkins (1954) as a parasite of ova of the crabs Pinnotheres pisum (Pennant) and Gonoplax angulata (Pennant) and was artificially induced to attack developing eggs of five other species of marine crustaceans: Typton spongicola da Costa, Crangon vulgaris Fabricius, Palaemon serratus (Pennant), Macropodia sp. and Portunus depurator (L.).…”