SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '75687c1b2d3fc156c2818041944765d15f98a97f7f2fda20fd17740596bdb061' 
  AND token = 'uioDxvAgLZj4lz1vMz4WS0nRYYsNiy2jr5zefaqO6wE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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