SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f04870811cff417338b34e020dbcb06164c01ee682432b07f2008a9d1f7f71db' 
  AND token = 'KlE4c83NDLl4O03iFroM5LYQ2G/Da96R+SHXelo3VvA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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