SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '94980c9a67e84a4e4e0120ec8c30c6171f92af592e627d98e7c78148ef99f3f8' 
  AND token = 'ytf1NqZ8Nvc7iPjBVhv6whnlKoOR+JL0Bg/gaVuQu2o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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