Boletellus Ananas

''Boletellus ananas'', commonly known as the pineapple bolete, is a mushroom in the family Boletaceae, and the type species of the genus ''Boletellus''. Previously known as ''Boletus ananas'' and ''Boletus coccinea'' (among other synonyms), the species was given its current name by William Alphonso Murrill in 1909.

The fruit body is characterized by the reddish-pink (or pinkish-tan to yellowish if an older specimen) scales on the cap that are often found hanging from the edge. The pore surface on the underside of the cap is made of irregular or angular pores up to 2 mm wide that bruise a blue color. It is yellow when young but ages to a deep olive-brown color. Microscopically, ''B. ananas'' is distinguished by large spores with cross striae on the ridges and spirally encrusted hyphae in the marginal appendiculae and flesh of the stem. Two varieties of ''B. ananas'' have been described.

It is distributed in southeastern North America, northeastern South America, Asia, and New Zealand, where it grows scattered or in groups on the ground, often at the base of oak and pine trees. Like many other boletes, this species is considered edible, but it is not recommended for consumption.

Taxonomy

The species was first named by Moses Ashley Curtis as ''Boletus ananas'' in 1848, based on specimens he found near the Santee River, in South Carolina. In 1909, William Murrill described the new genus ''Boletellus'' and made ''Boletellus ananas'' the type species. According to Murrill, the taxon ''Boletus isabellinus'', described by Charles Horton Peck in 1897 from specimens collected in Ocean Springs, Mississippi, is a synonym of ''B. ananas''; Peck described this species from undeveloped specimens. Wally Snell later doubted Murrill's conclusion in a 1933 publication; he considered the differences in the spore structure too great to consider the species conspecific with ''B. ananas'', although he admitted it was impossible to come to any definitive conclusions until mature fruit bodies and spore prints were available for study. Rolf Singer and colleagues (1992) suggested the name ''Boletellus coccineus'' for ''Boletellus ananas''. Singer created this name, however, in the mistaken belief that the earliest available name for the taxon was ''Boletus coccineus'', proposed by Elias Magnus Fries in 1838. However, Fries's name is an illegitimate later homonym (compare with ''Boletus coccineus'', named by Bulliard in 1791), and Singer's combination is actually based on ''Strobilomyces coccineus'', named by Pier Andrea Saccardo in 1888. The earliest available name for the species is therefore ''Boletus ananas'' M.A. Curtis 1848, the basionym of ''Boletellus ananas''.

''Boletellus ananas'', as the type species of the genus ''Boletellus'', is in section ''Boletellus'' that Singer based on the scaly, dry cap with red-pink tones, a marginal veil that clasps the stem when immature, and longitudinally ridged spores that are greater than 16 Î¼m long. The genus name ''Boletellus'' means "small boletus", while the specific epithet ''ananas'' alludes to the name for pineapple, referring to the pineapple-like pattern of scales on the cap surface. The mushroom is commonly known as the "pineapple bolete".

Description

The cap of ''B. ananas'' is wide and plano-convex (flat on one side and rounded on the other). It is covered with squamules (small scales) that can be either pressed against the cap or curved back on itself. The squamules range in color from reddish brown to red-tan, to pink to pinkish gray, and they are more concentrated and more scaly in the center of the cap, extending out of cream to light orange-pink to light pink-red floccose