SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '654cac92e975ff374bcbff615fb9c48aa78870bf2d187526d56aa964bd0c2ec7' 
  AND token = 'jSVxmWiPbsFLZWyrbuDlS5ykmo5sgPyj/6lj05xzEwA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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