SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd5211feae5cb974b3a72a9778d4d2ff07d44db71bc251b1e6c824cc15a3082cc' 
  AND token = 'QuzwLvYP89GNQwntVdiXiOquf6u++ulTnvWvCQM4/S8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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