SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '18577e50ddaaf854312fb86563eaa932176c8e6e998f7cd38a9a06cca5c1651b' 
  AND token = 'zmCGpgy2TRdjzFtkEZd2Q/Y5TFfK2Iwy8kfbzKVeQic=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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