Melanie, none of the black or mainly black beetles in the UK are venomous. Some will exude foul secretions but not toxins. As with ingesting anything unusual, transient gastrointestinal distress in the form of inappetence, vomiting and/or diarrhea can arise but Owen wasn't intoxicated. There's no reason to induce emesis or treat in any manner.
Please respond with further questions or concerns if you wish.
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