SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7f909f33e06c22d9c56414d82be1dc60d7f074df668be8a3a24e85145aaef365' 
  AND token = 'bsLf8jhEgT0WYyU/m94qX+4KKTbSgJpz4RwjPk35tgk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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