SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3235b1030769632b855456ff6ca09078be2b21421cef0c83c645c09b10f49359' 
  AND token = 'HlywxI6Vuh+O/Yog8lN29LZf+7uu7BmVLNFmH5fT1WQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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