SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2bc718db0c30dc5e8addcc2a2c6976e9a453235d45d293076ab7b1e9cbc475bb' 
  AND token = '0lWWkQz/aDYZOevvsnAlC0Z+4Aja2zTcWXfySWFU7k4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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