SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f9063f94cf386b01c91e7cf244c0ffe01528cfd76de585a6c444b1dd4f04948e' 
  AND token = 'hTj6MgGxYoYJV+qaA2IxR2w0kBh6NVqYyg+bgljDyew=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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