SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2d1c4013a5f808317a1a09df0fa8b4e5257f8a57f4a706b3554778ece92098f4' 
  AND token = 'ZXRqdZjRvYqZ4qrcfcjnP6+ICbzZ+UQuOejnkh3RP7o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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