SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7beb470ae93f58c0d3b41d2d237408d0159887ce94b52881748e8fd7d3b346c3' 
  AND token = 'eTpdSv93ZiEaV5ZleJm1jrhGgpgB/L+VDdAgoASfckM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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