First record of Hagen’s batwing Atrophaneura hageni (Rogenhofer, 1889) (Lepidoptera: Papiolinidae) in southern Sumatra, Indonesia

Hagen’s batwing Atrophaneura hageni (Rogenhofer, 1889) (Lepidoptera: Papiolinidae) is endemic to Sumatra and it was previously known only from North Sumatra and West Sumatra provinces. Here we report the first record of this species from South Sumatra. A male individual of A. hageni was recorded on 19 April 2018 in the Pagar Alam District, South Sumatra Province, Indonesia. Our record represent the most southern locality in the range of this rare highland species.


Introduction
The swallowtail butterflies (Lepidoptera: Papilionidae) is a group with more than 500 species globally (Kirton 2014;Hoskins 2015) that contains many of the largest and most beautiful butterfly species (Hill & Abang 2010). This family is known as swallowtail butterflies because many species have a tail at the hindwing tornus (Holloway et al. 2011). There are 24 Papilionidae species listed as precious and protected Indonesian butterflies, and these are the butterflies of highest conservation concern in Indonesia (Peggie 2011).
The genus Atrophaneura Reakirt, [1865] contains tailless butterflies somewhat resembling the genus Troides Hübner, [1819] at all stages of the life cycle. The larvae have large spiny tubercles, and feed on Aristolochiaceae (known as Birthwort) species. The adults are smaller than those of Troides and have shorter wings (Ek-Amnuay 2012). There are up to five Atrophaneura species in Sumatra. Atrophaneura hageni is a rare endemic butterfly having a range restricted to mountain forest in northern Sumatra (North Sumatra to West Sumatra provinces) (de Niceville & Martin 1896;D'Abrera 1982;Tsukada & Nishiyama 1982). Ecologica Montenegrina 28: 26-30 (2020) This journal is available online at: www.biotaxa.org/em This paper report the first record of A. hageni in the South Sumatra Province, providing an evidence that the range of this species may be broader than it was expected.

Materials and Methods
A field survey was conducted on 19 April 2018 in Kampung Empat Village (4°02'83''S, 103°08'99''E), Dempo Selatan Subdistrict, Pagar Alam District, South Sumatra Province (Figs. 1-2). This site is situated within the Dempo Mountain Protected Forest Area, in plant cover of height canopy which various plant species are abundant, e.g. Ficus spp., Clibadium surinamensis L., Pandanus sp., Alsophila junghuhniana Kunze, Litsea sp., Lithocarpus sp., Schima wallichii (DC.) Korth., and Vanda sp. The area is very close to the Dempo Mountain, bordering with a tea plantation. The altitude is 1,600 m above sea level, an area of lower montane forest in Sumatra (1.200 -2.100 m) as defined by Whitten et al. (2000). On one occasion, our team observed and photographed a large black butterfly perching at Ficus sp. and Alsophila junghuhniana. Unfortunately, we are unable to collect a specimen due to a large distance and rapid movements of the butterfly. However, it was identified as A. hageni based on the combination of specific morphological characters using the series of photographic images (Figs. 3-4).

Results and Discussion
The butterfly was identified as a member of the genus Atrophaneura by its large-medium size, white dorsal side of the head, entirely black body, black forewing with whitish shadow on venations, black hindwing with a white large spot in the post discal and submarginal area, and with four series of black spots (Fig. 3-4). These patterns are constant for the Atrophaneura priapus group. In Sumatra, there are three species of white headed Atrophaneura, that is: A. hageni, A. priapus (Boisduval, 1836), and A. sycorax (Grose-Smith, 1885) (D'Abrera 1982; Tsukada & Nishiyama 1982). The white headed Atrophaneura individual found in the Pagar Alam District was identified as A. hageni by its specific characters compared to A. priapus and A. sycorax. The butterfly differs from Atrophaneura sycorax by an entirely black dorsal surface of the abdomen and from A. sycorax by having a more than apical half of the body yellowish-white. The butterfly is very similar to Atrophaneura priapus by sharing white head and specific wing patterns. However, the latter species has more elongate hindwing, a white spot marking in hindwing extending between radius and discocellulars zone, and a smaller series of black spots within the white area in the hindwing (D'Abrera 1982; Tsukada & Nishiyama 1982;Harada et al. 2012). The butterfly from Pagar Alam District, South Sumatra differs from a set of characters listed above by its distinct white color in the head area, a more rounded hindwing, a white spot marking in hindwing absent or not extends to the area between radius and discocellulars zone, and by a larger series of black spots within the white area in the hindwing. Based on the specific characters listed above and appropriate guides (D'Abrera 1982; Tsukada & Nishiyama 1982;Harada et al. 2012), the butterfly found in the Pagar Alam district was identified as a male of A. hageni. The male was considered rarely seen than female (de Niceville & Martin 1896).
Atrophaneura hageni is endemic to the high-altitude regions of Sumatra. It was found in mountain jungles above 1,000 m altitude in the Karo Hill (3°N), North Sumatra Province, while its range extends to the Padang District (0°S), West Sumatra Province, in which this species occurred above 1,500 m altitude (Tsukada & Nishiyama 1982). However, it has never been reported from South Sumatra, and it was assumed that in the southern part of the island this species is replaced by Atrophaneura priapus (Tsukada & Nishiyama 1982). An old record labelled as Teluk Betung (Lampung Province) in 1928, coastal zone area of southern Sumatra (Creuwels 2020), must be error, because A. hageni is high altitude species. The record of A. hageni in the Pagar Alam District (4°S) represents the most southern occurrence of this species; approximately 1,000 km south of the Padang District.  Additional field surveys and collecting efforts are needed to estimate the status of A. hageni at the Pagar Alam District, i.e. if it is a local resident population or a single vagrant individual of this rare taxon. In our opinion, A. hageni was not previously recorded from South Sumatra due to the lack of entomological surveys in mountain forests of this area. This species is likely threatened by forest fragmentation and other kinds of anthropogenic impacts. Finally, our record is of importance for future checklists of Papilionidae at regional and global levels (Scriber 1995), particularly as a tropic archipelagic country, Indonesia has high level of endemism in animal distributions, including butterflies (Peggie 2011).