SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4ce292093d4b7a55b863137177bd776da83478547ddaa7ceb62fa3725d972b00' 
  AND token = 'BSWYBiee+PhtLQ+1CeoIqR1HMefVg5miYgBs9FwQJ6E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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