M. Yusoff

OBSERVATIONS ON TROPICAL ARENICOLOUS MARINE FUNGI ON DRIFTWOOD FROM MALAYSIA AND SINGAPORE

Fourty-four fungi growing on sand associated with driftwood collected at various beach sites in Malaysia and seventeen fungi growing on buried wood collected from Singapore are recorded. The most frequently collected species were Periconia prolifica, Savoryella appendiculata, Corollospora pulchella, Trichocladium cf. alopallonella. Other fungi commonly collected included: Carbosphaerella leptosphaerioides, Corollospora tnaritima, Corollospora colossa and Zalerion varium. Fifteen fungi are new records for Malaysia and seven are new records for Singapore. Eleven arenicolous marine fungi have been recorded in this study and the occurrence of arenicolous fungi at different geographical regions is discussed.

Ultrastructure of Antennospora salina comb. nov.

The ultrastructure of the ascospore and appendages of Halosphaeria salina was studied. Ascospore walls comprise a two-zoned mesosporium, the outer more electron-dense, and an electron-dense episporium enclosed by a layer of mucilaginous material. Ascospores have 3–5 subpolar appendages at each pole that appear as electron-dense striations and an amorphous core. Striations arise as outgrowths of the outer zone of the mesosporium, which is thickened at the point of attachment of the appendage to the spore wall. Halosphaeria salina is compared to H. appendiculata and Antennospora quadricornuta . It has more features in common with A. quadricornuta , particularly the ontogeny of the spore appendage, and is therefore assigned to the genus Antennospora .

Corollospora besarispora, a new arenicolous marine fungus from Malaysia

A new species of Corollospora, C. besarispora is described from sand grains in association with driftwood, collected at Turtle Bay, Pulau Pangkor, Peninsular Malaysia. Corollospora colossa was also collected from sandy beaches in Malaysia, and most closely resembles C. besarispora. The species are compared and distinguishing characters highlighted.

Ultrastructural studies of developing goat oocytes in vitro

The structure and distribution of organelles within developing goat oocytes at various stages of incubation were studied. In oocytes with 5 or more layers of cumulus cells, at 0 h of incubation, the zona pellucida had developed although zonation was not evident. Lipid bodies were present but no mitochondria were observed. At 20 h, the zona pellucida had differentiated into thicker and thinner regions. Clusters of membrane-bound electron-transparent bodies were present in the perivitelline space. The mitochondria were fully developed, distributed evenly and usually in close proximity with dilated endoplasmic reticula. Cortical granules were distributed at the periphery. At 40 h of incubation, a number of mitochondria was hooded. In oocytes of 2 to 4 layers of cumulus cells at 0 h, the zona pellucida was penetrated by cumulus cell processes, and the mitochondria were not well developed. However, in 20-h incubated oocytes, fully developed mitochondria, many of which were hooded, could be observed. Clusters of membrane-bound electron-transparent bodies were also observed, while cortical granules were at the periphery. In cumulus-free oocytes, zonation within the zona pellucida was indistinct. Very few vesicles and lipid bodies were observed. At 20 h, mitochondria were sparsely distributed and were not well developed and lacked cristae. At 40 h, the zona pellucida was less compact, and the membrane-bound electron-transparent bodies were less numerous compared with those of the other groups. Endoplasmic reticula were not dilated, and cortical granules were few and had no definite pattern of distribution.