SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fb444346ba71abd441955e6734600b0aab1b620f48e9b41a698297397366376f' 
  AND token = 'nbAfkhz27XpIqKKBeocSD7kPaAJrHuZsb28Yqmi8TXI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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