SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '0b4c303b7e5cd2324b6be9293c21df41e5a22d2a143c4358a9d722baded764c6' 
  AND token = 'nWUScYD2jzZ2lXWtQs/VqKXGo0w+DxyCORDpCLsTfbI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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