phialiform

Phialiform is an adjective describing something bottle-shaped or flask-shaped. In biology and mycology, the term is used to describe conidiogenous cells that are bottle-shaped, known as phialides, which produce conidia from their open apex.

A phialiform cell is typically elongated with a narrow neck and a broader base. During conidia formation, the phialide extends a conidium at its apex but changes little in overall shape; conidia are released from the tip and new ones continue to form in sequence. The structure is distinct from annelliform (annellidic) conidiogenesis, where the conidiogenous cell leaves ring-like scars as successive conidia are formed along its length.

In fungal taxonomy, the presence and arrangement of phialiform conidiogenous cells are used as characters to distinguish genera and species. Phialides are common in several fungal families, including some Aspergillaceae and related groups, and occur on a variety of conidiophores from simple stalks to complex branching structures.

Related terms include phialide, conidiogenesis, conidiophore, and annellide.