SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '53710a7cc70bb78dcb3d383a9e310caa8f190751304d293e4fab04d8a7065d6e' 
  AND token = '/M7bV3xS9EjXzpx39K2ARNIsiHanUDC9gmSNvfIGIGo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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