SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a0474de64a12ddd7792a571d9a7015e12033a7086b080153c59c0600421d2ed7' 
  AND token = 'gaRUCKtyDAYrowQBKIhRlhWCQ/tvkS/nltXEARobH/o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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