SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '82a0fc7745b9d6ab843cdc2493a7d8f384829308130696ae5a40b4785ab9e556' 
  AND token = 'hZuQRTb1dngtKF29g6b2pRkBWJxuxpJfDugrXhCCAp4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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