SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '000af3daec17f7885443d072bd2f8bdfe601df3bb4314a59ad17db26de4ddae5' 
  AND token = 'feNXPLzstIde2jMtrkHrmy+PH+t3JOTiDzn/nGKwf+s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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