SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3df06e1c8546f26493bd1a1cbbf66d7900de61b6a1326a581da229a791a467a4' 
  AND token = 'QSrJ/MrEvupnLuadSxBjtdKIddTOGtWTvl6BkSP0qEM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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