SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '574c5223a309f631ef026e523541d3a694bdc1022677b3114b3de570b9f3e664' 
  AND token = 'Xfhi49Gm0lYpiviDGiSp7iNoBdTcWojO2fgWje22o/0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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