SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '314da177f2bf141ab679ca9dab2bb8b556bcaf51c2f52828306b64147a267698' 
  AND token = 'xrBh7wQHo8+UdHqURjxnGv3g3GdcYMhbPmV0EUWdtvI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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