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Remarks (public):For a complete description including images see www.cababstractsplus.org/dfb 
Remarks (internal):With the upsurge in interest in entomogenous fungi and their possible use in biological control programmes, this sheet and No. 714 include the two most common nectriaceous fungi with Fusarium conidial states which are parasitic on scale insects. In fact ,only three such fungi are recorded from scale insects. These are Nectria flammea (anamorph Fusarium coccophilum), Nectria aurantiicola (F. larvarum var. larvarum) and Calonectria diploa (F. juruanum). The latter is seldom recorded. All these are easily separated from each other both in their perithecial state which occurs on the host or by the conidial state formed on the host or in culture. They are not confined to specific insect hosts and often occur together in the same infection. More work is required on their epidemiology.
 
Description type:Non-original description 
Description:Nectria flammea (Tulasne) Dingley, Trans. Roy. Soc. N.Z. 79: 189, 1951.
Sphaerostilbe flammea Tulasne, Selecta Fungorum Carpologia 3: 103, 1865.
Conidial (anamorph) state: Fusarium coccophilum (Desm.) Wollenw. & Reink., Die Fusarien, p. 34, 1935.
For further synonymy see Booth, 1971.
In nature this species occurs as a parasite of scale insects. A byssus of white mycelium form and ultimately develops into astroma along one side or all round the infected insect. The sporodochia develop on this stroma; their position becoming obvious as the orange mass of conidia develops. As these dry they often form a conical, apparently horny, mass over the scale insect. Later, perithecia develop around the edge of the parasitised insect and even when these are scattered up to twelve perithecia may develop around each scale. The perithecia are 380-400 µm diam., globose with a small ostiolar papilla and finely roughened outer wall. Asci are unitunicate, cylindrical with a rounded end and short stalk, they have six to eight monostichous to obliquely monostichous ascospores and are 90-125 x 9-12,5 µm. Ascospores are ellipsoid to ovate, 16-20 x 7,5-10 µm, with a smooth wall and a single central septum. In culture the fungus is slow growing and the aerial mycelium is sparse and floccose but becomes felled and white to pale orange. Macroconidia develop on sporodochia similar to those on the host and from a palisade of cylindrical phialides, 20-30 x 4-5 µm, formed over the surface. Macroconidia appear hyaline but are orange in mass. They are cylindrical and curved towards the beaked apex. When mature they have 6-10 thin transverse septa and are 80-100 x 6-7 µm.
Hosts: The fungus occurs on a variety of scale insects, Aspidiotus nerii, Hemiberlesia rapax (53, 1-694), Pseudaulacaspis pentagona (55, 2093) etc. on a wide range of hosts, Acacia, Brachyglottis, Camellia, Citrus, Coffea, Morus, Ribes, Salix, Thea, Weinmannia, etc.
Geographical distribution: Australla, Belize, Fiji, India, Japan, New Zealand, Papua and New Guinea, Tanzania,
Tonga, Uganda, South Africa, Sarawak, Zambia.
Physiologic specialization: None recorded.
Transmission: Airborne by ascospores or by moisture droplets as conidia.
Literature: Booth, The Genus Fusarium, Commonwealth Mycological Institute, pp. 237, 1971.

 
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