SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8149aeb599ced4b132ec7b3a0d38b0214d2d9dd64911c9b746283966c48624ef' 
  AND token = 'tB4gdSLQHu4M59SeqiQqy39zZgt/gG+hVuxzELhCIq4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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