SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7e86c2bf9554de790319f10387c744b3d73cbcb87d4fb29ebef6e6e898e01b99' 
  AND token = 'RTytCMRTPFFnYHbgeLm6MVIW5LyrBkg0l8+cXyc+mu8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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