dinoflagellate apical groove

GO:0097685 · Other · Subcellular region · Proposed

A cell surface furrow (or groove) found on a dinoflagellate apex. It typically loops around the apex. [GO:0097685]

Synonyms: apical groove

Part of: dinoflagellate epicone (GO:0097613)

Taxonomic distribution

NCBITaxon:2864 Dinophyceae — VARIABLE: GO:0097685 places this apical cell-surface furrow in Dinophyceae; the apical groove is a named morphology of dinoflagellate apices. [GO:0097685]
NCBITaxon:77300 Margalefidinium polykrikoides — COMMON: Cochlodinium polykrikoides, the species examined in the 2010 electron-microscopy study, has a U-shaped apical groove at the dorsal side of the epicone. [DOI:10.1111/j.1550-7408.2010.00491.x]

NCBITaxon:77300 Margalefidinium polykrikoides — Dinophycean model described as Cochlodinium polykrikoides in the electron-microscopy study that characterized the apical groove and flagellar apparatus. [DOI:10.1111/j.1550-7408.2010.00491.x]

The dinoflagellate apical groove is a cell-surface furrow that typically loops around the cell apex and belongs to the epicone region.

Subject	Predicate	Object	Evidence
dinoflagellate apical groove	is a	cell surface furrow	`GO:0097685` The GO graph links GO:0097685 to GO:0097610 by rdfs:subClassOf.
dinoflagellate apical groove	is part of	dinoflagellate epicone	`GO:0097685` The GO graph links GO:0097685 to GO:0097613 by BFO part-of. `DOI:10.1111/j.1550-7408.2010.00491.x` Iwataki et al. 2010 described the apical groove position on the dorsal epicone in Cochlodinium polykrikoides.

CURATION_TODO (OPEN): Add apical-groove molecular components only after directly localized constituents and exact source-neutral family groundings have been identified. GO and the ultrastructure literature define the apical groove as a dinoflagellate cell-surface furrow, but this pass did not find exact family-level evidence for apical-groove-specific molecular constituents.

GO:0097685 Gene Ontology cellular-component term for the dinoflagellate apical groove.
GO:0097610 Gene Ontology cellular-component parent term for cell surface furrow.
GO:0097613 Gene Ontology cellular-component term for the dinoflagellate epicone.
PMID:20561119 PubMed record for Iwataki et al. 2010, the apical-groove ultrastructure study cited by GO:0097685.
DOI:10.1111/j.1550-7408.2010.00491.x Iwataki et al. 2010 examined the external and internal ultrastructure of Cochlodinium polykrikoides with reference to the apical groove and flagellar apparatus.
DOI:10.1016/j.hal.2017.01.008 Gomez et al. 2017 established Margalefidinium gen. nov. for Cochlodinium polykrikoides and allied species.

2026-10-02T15:51:53Z codex · CREATED_RECORD — Scaffolded by scripts/new_record.py
2026-10-02T15:53:07Z codex · EXPANDED_RECORD — Added apical-groove synonymy, GO cell-surface-furrow parentage, dinoflagellate-epicone parthood, Dinophyceae and Margalefidinium polykrikoides taxon evidence, a nonmechanistic epicone-topology graph, and a curation TODO for apical-groove molecular components.
2026-10-02T15:53:56Z codex · REFINED_CANONICAL_EXAMPLE — Retargeted the Margalefidinium polykrikoides canonical-example citation to the 2010 apical-groove ultrastructure study while keeping the 2017 Margalefidinium taxonomic-transfer paper as record-level evidence.
2026-10-02T16:07:15Z codex · ADDRESSED_PR_REVIEW — Addressed PR #1921 review issues #1922 and #1923 by removing the Margalefidinium transfer claim from the DOI:10.1111/j.1550-7408.2010.00491.x taxonomic-distribution row and narrowing the GO:0097613 evidence note to the dinoflagellate epicone term.