SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9ec227a46106e1e2f4beb6d4206f090fc0212e29ec8728fb1e5870ee09fa3f65' 
  AND token = 'W5YVv0RxWAbMzutGmEVWCaX5dd9cjACs8mr5rpwa/Sg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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