SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5a549194ce11819e65a5fec8d10ce79a7f28c51093a9fd3c4a595919c7752e48' 
  AND token = 'clHEWOaviLqMaDPWWNU3Ti4ihbgfrmbnxIxikPHmEZg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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