SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6cb357b8c940a0615866205fd404e01ab386cc361825dc40d20246b979a471dd' 
  AND token = 'SdWlJfQDiYjzbGJXYavUeiWZCbi3mtxV/x6wuI8N4yU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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