SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2ab95bf1fadb5216f13bd6dc8c641f27e73bb04ff4fe384d00ce6276aa50aac7' 
  AND token = 'owKJpB/EsndRWNWHuAFP+SCSoi6y/YsYZl9fDYWX9sc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}