SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '74b45ed9f0e56d479bbebd26781d5a8e05b191dcb3649538b5392300772b571b' 
  AND token = 'XFNdO/L+WFTuLvLpivqg6j2WnJlGlZK3luJZRW0SQLw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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