SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e9d5c4f1dd5dc3ede354b120a2e856b1b80cf4e4e3a42e690ef1fb8d1d81e08e' 
  AND token = 'dYcLilTbdMVDFl1855GMZmut2d1lPYooyxSSqAisoj8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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