Adnate

grown fast to something; congenitally attached.
Historical Examples

The gills are thin, close, adnate, a delicate cinnamon-brown becoming darker with age.
The Mushroom, Edible and Otherwise M. E. Hard

When they are attached squarely and firmly to the stem they are said to be adnate.
The Mushroom, Edible and Otherwise M. E. Hard

Differs from C. stipitaria in adnate gills and dingy pileus.
European Fungus Flora: Agaricaceae George Massee

The gills are broad, close, adnate, whitish or pale cinereous.
The Mushroom, Edible and Otherwise M. E. Hard

Where the gills are not attached to it they are called free; slightly so, adnexed; and when wholly fastened they are adnate.
Among the Mushrooms Ellen M. Dallas and Caroline A. Burgin

The gills are subdistant, adnate, or decurrent, white or creamy-white.
The Mushroom, Edible and Otherwise M. E. Hard

The tubes are yellow, adnate, the tube surface plane or convex.
Studies of American Fungi. Mushrooms, Edible, Poisonous, etc. George Francis Atkinson

adnate to the perianth, and therefore around the ovary and not at its base.
The Manual of the Botany of the Northern United States Asa Gray

The cells forming a pair, are, on the branches, adnate to each other throughout their whole length.
Narrative Of The Voyage Of H.M.S. Rattlesnake, Commanded By The Late Captain Owen Stanley, R.N., F.R.S. Etc. During The Years 1846-1850. Including Discoveries And Surveys In New Guinea, The Louisiade Archipelago, Etc. To Which Is Added The Account Of Mr. E.B. Kennedy’s Expedition For The Exploration Of The Cape York Peninsula. By John Macgillivray, F.R.G.S. Naturalist To The Expedition. In Two Volumes. Volume 1. John MacGillivray

Habitat on fungi like C. tuberosa, from which it differs in adnate gills.
European Fungus Flora: Agaricaceae George Massee

adjective
(botany) growing closely attached to an adjacent part or organ
adnate
(ād’nāt’)
Botany Joined to a part or organ of a different kind, as stamens that are joined to petals. Compare connate.