Boletellus obscurecoccineus

Boletellus obscurecoccineus was originally collected in Java and described by Franz Xaver Rudolf von Höhnel in 1914,[2] and placed in the genus Boletellus by Rolf Singer in 1945.[3] In 2011, Nian-Kai Zeng and Zhu L. Yang synonymised the Asian species Boletus puniceus and Boletus megasporus with Boletellus obscurecoccineus.[1] Boletus puniceus, originally described from Kunming (Yunnan, China) in 1948,[4] and later transferred to Xerocomus in 1979[5] and Boletellus in 2002,[6] was already suspected by E.J.H. Corner in 1972 as being conspecific with B. obscurecoccineus in his monograph on Malaysian boletes.[7] Boletus megasporus was described from the Xizang Autonomous Region of China in 1980.[8] Comparison of the type specimens revealed no significant morphological differences between B. obscurecoccineus and B. megasporus.[1]

A brightly coloured and distinctive bolete, Boletellus obscurecoccineus has a rose-red or rhubarb-coloured, hemispherical to convex cap to a diameter of 7 cm (3 in), with an overhanging margin when young. The cap may crack in older specimens, and reveal the yellow flesh beneath. The adnexed pores are five- or six-sided and yellow. They bruise blue in some specimens (although not generally in Western Australia). The narrow stipe lacks a ring, and may reach 9.5 cm (3.7 in) tall with a diameter of 2 cm (0.8 in). It is reddish and scaled overall, fading to yellow under the cap. The spore print is a dark brown. The mycelium is white.[9] There is no significant odour and the taste is mild. Under the microscope, the elongated pale yellow spores measure 14.5–19.5 by 6–7.5 μm.[10]

The distribution includes Korea,[13] New Guinea, Java, Borneo, Japan,[14] and Taiwan.[15] Within Australia, the rhubarb bolete has been recorded from southwestern Western Australia, and the southeast of New South Wales, and into Victoria and Tasmania.[10]

The rhubarb bolete is an ectomycorrhizal species, found in the leaf litter of eucalyptus forests in Australia, and with oak and other deciduous trees in Asia.[12] Fruit bodies appear over the summer and autumn, from July to November.[9]

Despite its English name, whether this mushroom is safe to eat is unknown; however, the boletes are not a deadly poisonous mushroom variety, although many individuals get gastrointestinal distress from certain species, particularly species with red pigmentation.[10]