SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9c462acb19ce37c467eff17567a698e7f6133ec46a6a9aacbc85cbeb9e78d5d7' 
  AND token = 'MmeM++Bk5bqiSf4KVRxh/GkVlGlWloGbeALATWUPk+8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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