SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6fa41962a770efc843ac1d485b5b3a8cc1825654443495551340df625662ea59' 
  AND token = 'UI5T+JIDBX53WReY/J9H5Vp2I3NQjn7ZqNWnf2mfC8Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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