SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7def6c647159a6dfc41e77934b67dd685a6b8bb8340a7ba618d1a4b3a3fe15bb' 
  AND token = 'BXnirhEydMTaBeo+GWexiAUwB4csgpMxJ6J3WuuCFPM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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