SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '625fc2aeb6b28afe41dec6a207d1972037adc84780cc148b51edff10e0463172' 
  AND token = 'Pk6y0WYvKlF8nipyA95PbzFCX5wl2g89WPtln9/fQr0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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