The first record of the monospecific genus Rhinopalpa (Lepidoptera: Nymphalidae) from China

Abstract Background The family Nymphalidae is the largest group of butterflies with high species richeness. Rhinopalpapolynice (Cramer, [1779]), a forest species, was discovered in the mid-stream of the Yuanjiang-Red River Valley of Yunnan Province for the first time, which represents the first record of the genus Rhinopalpa in China. New information The species R. polynice (Cramer, [1779]) is the first record of the genus Rhinopalpa from China. The specimen was collected in the mid-stream of the Yuanjiang-Red River Valley of Yunnan Province. The female genitalia are described for the first time.


Introduction
Nymphalidae is a cosmopolitan family of Papilionoidea with high species richness, which includes about 6,100 species in 12 subfamilies and 350 genera (Ackery et al. 1999, Hsu 2013, Wu and Hsu 2017. Most species are medium or large-sized and variable in wing shapes, colours and markings (Wu and Hsu 2017). Some species also exhibit strong seasonal phenotypes (Hsu 2013, Wu andHsu 2017).
The genus Rhinopalpa C. & R. Felder, 1860 is placed in subfamily Nymphalinae (Savela 1990, Inayoshi 2021. According to the molecular study including genus Rhinopalpa, this genus was regarded as Victoriini (Wahlberg et al. 2005,Chazot et al. 2019. The genus Rhinopalpa contains only one species, Rhinopalpa polynice (Cramer, [1779]) , which is distributed widely from Indochina to Indonesia and the Philippines, with 10 subspecies described to date (Savela 1990, Inayoshi 2021. Rhinopalpa polynice has two subspecies in mainland SE Asia, ssp. eudoxia from Indochian to Malay Peninsula and ssp. birmana (Savela 1990, Osada et al. 1999, Inayoshi 2021. Rhinopalpa polynice is a typical forests species and the larvae can develop successfully to adult on species of Poikilospermum (Cecropiaceae) and Dendrocnide (Urticaceae) in the wild . Three specimens were recorded from the Red River Valley in North Vietnam , Inayoshi 2021. However, there has been no record of this species in China.
In this study, a female R. polynice was collected from Yuanyang County, southeast Yunnan, China, which sits in the mid-stream of the Yuanjiang-Red River Valley and is isolated from the sites in North Vietnam where R. polynice was previously recorded. The female genitalia are described for the first time. The specimen, collected in this study, is the first record of the genus Rhinopalpa in China. Both specimen and dissected genitalia are deposited in the insect collection of Southwest Forestry University (SFU), Kunming, China.

Materials and methods
Spread specimens were photographed by Canon 5DS (Canon, Japan) with medium grey background and the photos were adjusted using Adobe Photoshop CS (Adobe, USA).
To observe the female genitalia, the abdomen was treated with 1 ml 10% sodium hydroxide solution to digest soft tissue at 70℃ for 1 h and then dissected in a water-filled Petri dish under a stereoscope. The genitalia were then transferred to 80% glycerol for 12 h to render them transparent. A solutiion of 2% chlorazol black was used to dye the membranous parts for 10 min in order to obtain better photographic results. Photographs were taken with a Nikon SMZ1500 stereoscope (Nikon, Japan) and automatically stacked using Helicon Focus 7.5.8 (Helicon Software, USA). After observation and photography, a piece of card was cut, the genitalia were fixed to the card by white emulsion and pinned with the specimen to avoid confusion. The photographs were adjusted and arranged using Adobe Photoshop CS (Adobe, USA). Terminology of the female genitalia follows Hu et al. (2021). Description Female (Fig. 1): Forewing length 37 mm. Body brown covered with short hair dorsally, labial palpi brown, antenna straight and dark brown, legs greyish-yellow. Forewing: broad triangular with obvious zigzag termen, two angles at ends of veins M and CuA , forming hook-shaped apex; upperside brownish in basal one third, discal area reddishbrown, postdiscal to termen area dark brown, space CuA with small subterminal black spot; underside dark brown, six fine purplish zigzag lines in brown basal area, six serial subterminal ocelli with purple pupil, brown iris and purple ring, terminal area with two parallel narrow purple wavy lines. Hindwing: square with obvious zigzag termen, acute short tail at end of vein M ; upperside with same colour configuration as forewing, three small subterminal black spots in spaces M1 to M ; underside with same colour configuration as forewing, including the purple lines in basal area, seven serial subterminal ocelli as those of forewing.

Taxon treatment
Female genitalia (Fig. 2): Papillae anales round and narrow. Lamella antevaginalis sclerotised and narrow, lamella postvaginalis sclerotised, with claw-like central part and two narrow lobes at both sides. Ductus bursae tubular and membranous, rather slender. Corpus bursae oval, signa comprised of two patches of tiny granules at both sides near base.

Discussion
China is a country with high biodiversity of butterflies with about 2020 species in recent records (Wu and Hsu 2017), especially in south Yunnan where the environment is highly heterogeneous (Zhang et al. 2020). In recent years, many new taxa and new records of  butterflies were described and discovered (Hu and Zhang 2010, Hu et al. 2012aHu et al. 2012b, Lang 2012, Lang 2017, Zhang et al. 2020). Most of these new records are forest species and were previously mainly recorded in Indochina (Fig. 4;Savela 1990, Osada et al. 1999, Ek-Amnuay 2012Monastyrskii 2019, Inayoshi 2021). As south Yunnan is adjacent to Indochina, it is logical that a number of Indochinese species could also be found in south Yunnan as the environment is similar (Li 1995, Chen et al. 2012. In light of this situation, the distribution range of these Indochinese species could be much wider than we know. Amongst these species, forest species like R. polynice are difficult to notice because of their particular habitat requirements and lower tolerance to human disturbance .
The first record of the monospecific genus Rhinopalpa (Lepidoptera: Nymphalidae) ... morphological differences. In this study, as we only examined one specimen, it is impossible to further analyse its subspecies status with such limited material. Hence, the subspecies identity of R. polynice in Yunnan still requires future study.