SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a3461b39809252f58afe02239d5d1796154847c0f126ab0023aac0a52ebcd6f2' 
  AND token = 'AC62VHjltAjBtJpozMaoiq+WxE8LxQ/uE5z+yGVYnDM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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