SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3211409f1e13ce50fbd44084d3b9e3cf80a9515b1b320e296824fb01a21d7ff5' 
  AND token = 'cliaHv1e/RJSeJicCK6827uKam4KEBoc/Hl9o44KCkk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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