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 Restiosporium dissimile
BiostatusPresent in region - Indigenous. Endemic
Images (click to enlarge)
Caption: Fig. 1 Cryptic sori of Restiosporium dissimile in the capsules of an infected Apodasmia
similis. Enlarged, four sori(type). Infected, mature capsules rupture at their bases, fall off the
plants, and the spore balls are |
Article: Vánky, K.; McKenzie, E.H.C. (2002). Two new species of Ustilaginomycetes from New Zealand. New Zealand Journal of Botany 40(1): 117-121 (http://www.rsnz.org/publish/abstracts.php).
Description: Sori (Fig. 1) in the capsules destroying the seeds and filling the capsules with a black, first
agglutinated, later granular-powdery mass of spore balls, inconspicuous,lacrymiform, acute, c.
2 mm long and 1 mm wide at their base, hidden by the somewhat spreading floral envelopes.
Infection systemic, all capsules of a plant being smutted. Spore balls (Fig.2, 3) variable in
shape and size, globose, ovoid, ellipsoidal, elongated or irregular, (30-)40-80 x 40-120(-140)
µm, dark olivaceous brown, opaque,composed of tens to maybe more than one hundred spores
which separate easily by pressure. Spores (Fig. 2, 3) variable in shape and size,
irregular, rounded or elongated, polyangular or subpolyangular,often with acute tips and also
with an acute edge along the meeting line of two flattened sides, 10.5-14.5 x 12-19(-22) µm,
olivaceous-brown; wall 1.5-4(-5) µm thick, uneven, thickest at the angles, apparently smooth,
in SEM inner spores and contact sides smooth, free surface finely and sparsely verruculose,
and partly also covered by remnants of sporogeneous hyphae as irregular squamae.
Habitat: HOST: On Restionaceae: Apodasmia similis (Edgar)B.G.Briggs & L.A.S.Johnson (=
Leptocarpus similisEdgar). Known only from the type collection.
Notes: ETYMOLOGY: dissimile, from Latin dissimilis, -is,-e = unlike, dissimilar, referring to the
dissimilarity to Restiosporium leptocarpi.
DISCUSSION: On the approximately 465 species of Restionaceae (Meney & Pate 1999) only
five smut fungi were previously known, belonging to two genera,Websdanea and
Restiosporium. The peculiar, monospecific Websdanea (Vánky 1997), in the Websdaneaceae
(Vánky 2001) (type W. lyginiae, Western Australia) produces bullate, pedicelled striae, filled
with loose spore balls, on the culms of Lyginia barbata. Restiosporium (Vánky 2000), in
the Ustilaginaceae (type R. meneyae, Western Australia) replaces the seeds, and the capsules
are filled with spore balls composed of rather easily separating, pigmented spores. Only five
species of Restiosporium have been published, including the one described in this paper,
although several more are under study.
Restiosporium leptocarpi (Vánky 2000) (type onLeptocarpus tenax, Australia), differs from
R.dissimile in having paler and larger (16-25 µm long) spores that are more rounded, without
acute tips or edges.
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