SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a57add0683d525a9caa0278daca2c9b8ab71172890f3c75166420b9695ba13a0' 
  AND token = 'y8stpFiWeYTQ2eQ7fzmynljBo7SaWmWnJrWkbYTWSYI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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