SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a1fd36f7c4004ca0a44f4b1241f4bb89d767af40d27a2470ddd74cbcb820722b' 
  AND token = 'pKRd4zvfGlfUl7YvY1yGOC4RwAAj+XlFwaJNotJHlFg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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