SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6c13eb84c2968429886051774ff820747fe06448f09fc7ab38982ab74bb9953a' 
  AND token = '9Wm/f/q5IM1xgGgv7owzbVADw5Ph6tkH4xiYO5dgqkY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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