ScienceAugust 29, 2026

apinnulate

ay-PIN-yuh-let

Definition

Lacking pinnules, which are the small, feather-like side branches found along the arms of many echinoderms.

Etymology

Derived from the prefix 'a-' meaning 'without' and 'pinnulate,' which comes from the Latin 'pinnula,' a diminutive of 'pinna' meaning 'feather' or 'wing'.

In the news

The article uses the term to describe the ancient sea lily Dendrocrinus simcoensis, noting that it lacks the fine side branches present in all living crinoids.

In the entire 485-million-year fossil record of sea lilies, only one fossil had ever been found with the tube feet the animals catch their food with, and a pair of crushed specimens from a Quebec quarry has now produced the second and oldest case, at about 452

Read the full article ↗

ScienceBlog.com

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