Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c9e09fa12943c7e14b1c961644fd940d7b7ab90fcb5aaf6bbb9a0c19a9d84035' 
  AND token = '6jfMDqLS/+T4xfhjOv34nTb9ivHnm5C3tBkS7pHfnF0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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