SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2c9d8b486c7baf683e2e227d48b1bd5f02387709bd82b1b5ac62be94d3ca3c7e' 
  AND token = 'qHvzHQ+N3IDCqTtwVhgGHPWZYl3tnIvlO3dZSt6Fi6c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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