SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e0cfe839c85ea71722466e79e3b320b0a6afd4d5cfdf14020b5411bac47fcc1f' 
  AND token = 'swKSdYekQlCLsXQxg6MAKfdKr+L2XTgkWgMIwR0qwq0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}