SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c3c69435f4ccbbd686073f665a27761123ff581d06254dd6759962a2af64c6a6' 
  AND token = 'XKohUAEfPSkwjFWY+Sck8JnIrwsz+9hnWFD71z/cXlY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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