SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'adb543bc73cadc1cbf8bef9e7522207e836de517f658784df8fe4483ea3ab956' 
  AND token = '1A4q9nTYn+uz8GsStG9V7R41wFxptQc0gFltHl9H8bE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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