SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9e147df4ad9989543218af33439d8f23b4f7c445c30a644207cbb195ad2164aa' 
  AND token = 'irhmthgI84TMVVuZB1T2UxbCrmYnZiQ98LXvjEzlFyo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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