SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ac45f79b15759aa4af8d4765dac93bb67ae1d89ca42ed4c1ec43c8dd2a1dbc90' 
  AND token = 'pwxMr6TQyn8O/hj1mPJ1wl5lcDKLUqIQs6QXLpN7qng=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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