Taxus cuspidata

T = 5: All parts except the red aril contain taxine alkaloids (A and B), potent cardiotoxins acting by Ca²⁺/Na⁺-channel antagonism on myocytes → bradycardia, AV-conduction block, diastolic cardiac arrest (Wilson et al., Toxicon 2001; Taxus cuspidata overview, ScienceDirect). T. cuspidata and T. baccata hold the highest taxine content among yews; humans are susceptible, and yew has historically been used for suicide. Lethal dose is very small and onset peracute (cardiac arrest mechanism, <2h). T = 5 is met via the LD/cardiac-arrest criteria (species-confirmed for cuspidata), independent of the death-documentation route → automatic RED.

A = 5: Lethal to essentially all animal species at very small doses; sudden death is frequently the only sign. Documented T. cuspidata lethality: Shetland ponies given 0.1 % body-weight green T. cuspidata foliage died ~15 min after onset of signs (J Vet Diagn Invest 2005); calf mortality from Japanese-yew clippings; canine poisoning (Evans & Cook 1991). Canine LDmin ≈ 2.3 g leaves/kg. → A = 5 (lethal all species, dose < 50 g). VET flag activated (A ≥ 4).

I = 0: Slow-growing ornamental/hedge conifer; bird-dispersed aril but no documented dense-monoculture formation or native-vegetation displacement in Europe. Absent from EU Regulation 1143/2014 and Ferrantia 93.

Core Indices — FXT + CHD:

• FXT (symptoms < 2h): peracute cardiac collapse; equine death ~15 min post-onset documented for T. cuspidata foliage. ✓
• CHD (ACCESS + ATTRACT + T≥1): ubiquitous urban hedge/ornamental (ACCESS); the red fleshy aril is a documented pediatric ingestion attractant for yews (ATTRACT), the enclosed seed being highly toxic; T = 5. ✓
• CLN — PENDING: taxine cardiotoxicity and animal/human lethality are firmly established, but a species-specific European human clinical criterion (A–E; e.g. Criterion B death 2016–2026) is attributable predominantly to T. baccata, not T. cuspidata. Per CLN rules, genus-level/animal data do not satisfy the index → flagged pending a primary T. cuspidata-specific European human source. Not provisionally closed.
• ALL = false (Taxaceae pollen allergenic but no species-level >1M-sensitized European attribution). THR = false (NE). BAN = false.

Auto Flags — VET (A ≥ 4). No ECO (I < 3). CMM DERM not assigned — dermal taxine absorption is a systemic route, not vesicating contact dermatitis.