Notes on some rare and elusive butterflies from Namdapha National Park, Arunachal Pradesh, India with rediscovery of two subspecies (Lepidoptera: Papilionoidea)

Notas sobre algunas mariposas infrecuentes y escurridizas del Parque Nacional de Namdapha, Arunachal Pradesh, India con el redescubrimiento de dos subespecies (Lepidoptera: Papilionoidea)

Introduction

Namdapha National park (27.391667ºN-27.661111ºN, 96.250556ºE-96.975833ºE, 200 m-4571 m) is in Changlang district of Arunachal Pradesh state in North east India and spans over an area of 1985.25 km.. The park shares its boundary with Myanmar in the South and East and Kamlang Wildlife Sanctuary of Lohit district, Arunachal Pradesh in the North. The region experiences a tropical climate and annual precipitation varies between 1400-2500 mm, 75% of which falls between April and October. Temperature varies between 5ºC-35ºC at lower altitudes and reaches below 0ºC at higher elevations. Relative humidity varies between 47-93% annually (ARUNACHALAM et al., 2004).

Namdapha National Park lies at the intersection of Himalaya and Indo-Burma global biodiversity hotspots (MYERS et al., 2000; MITTERMEIER et al., 2011). Biogeographically, it falls under Eastern Himalaya (2D) biotic province which lies at the junction of Indo-Malayan (Oriental) and Palearctic biogeographic realms (RODGERS & PANWAR, 1988). The park has a rugged topography with steep hills and narrow valleys and harbours a wide range of vegetation and habitat types (DEB & SUNDRIYAL, 2007). It has all major forest types of the region and with increasing elevation there is a transition in habitat from tropical wet evergreen forests to subtropical broad-leaved forests, subtropical pine forests, temperate broad-leaved forests, alpine meadows and perennial snow (DUTTA et al., 2008). The region has faunal and floral affinities with adjoining forests of South east Asia (MANI, 1974). A total of 1119 species of plants belonging to 639 genera and 215 families are reported from Namdapha National Park (CHAUHAN et al., 1996). It is also rich in its faunal assemblage with over 1399 species recorded so far (GHOSH, 1987).

One of the first inventory of butterfly fauna of the region after independence was undertaken by VARSHNEY & CHANDA (1971) where they documented butterflies from Tirap and Changlang districts. In their publication, ‘Butterflies of the North-Eastern India’ they reported six species of Pieridae, two species of Nymphalidae and one species of Lycaenidae from Arunachal Pradesh. BHATTACHARYA (1985) recorded a total of 84 species of butterflies from Namdapha National Park belonging to the family Papilionidae (21), Nymphalidae (42), Lycaenidae (10) and Pieridae (11). KUNTE (2010) rediscovered Symbrenthia silana de Nicéville, 1885 from North-east India where the species was reported from several localities including Namdapha National Park. SETHY et al. (2014) reported 113 species of butterflies under 73 genera from South-eastern part of Namdapha Tiger Reserve. Recently, a new species of Hypolycaena, Hypolycaena narada Kunte, 2015 was described from Namdapha National Park (KUNTE, 2015). THOMBRE & KEHIMKAR (2015) recorded Ideopsis similis persimilis (Moore, 1879) from Namdapha National Park, which was first record of the subspecies from mainland India. More recently, Zoological Survey of India (ZSI) conducted extensive surveys in Namdapha NP from 2016-2018 as part of a National Mission on Himalayan Studies (NMHS) project which has led to several interesting findings. Here we report the occurrence of eight rare and elusive species or subspecies of butterflies from Namdapha National Park (Map 1), including rediscovery of two subspecies after a gap of more than a century. Some of these findings significantly extend the known ranges of subspecies/species further North and all of them are new distributional records for the state of Arunachal Pradesh.

Notes on species

Family Hesperiidae Latreille, 1809 Subfamily Pyrginae Burmeister, 1878 Tribe Tagiadini Mabille, 1878

Capila pieridoides (Moore, 1878)

Calliana pieridoides Moore, 1878; Proc. zool. Soc. Lond., 1878(3): 687

Type Locality: “NE Bengal” (West Bengal, India).

Distribution: NE India, China, Myanmar, N. Thailand, Malaysia, N. Vietnam.

The genus Capila Moore, [1866] consists of 13 species and is distributed throughout the Oriental region (SAVELA, 2019), ranging from India, China, Myanmar, Thailand and Vietnam up to Sundaland (CORBET & PENDLEBURY, 1978). In India, it is represented by six species (VARSHNEY & SMETACEK, 2015) among which Capila pieridoides (Moore, 1878) is the only species confined to Indo-Chinese subregion (EVANS, 1932). Within C. pieridoides three distinct subspecies are recognized, namely Capila pieridoides chinensis Evans, 1932 which occurs in China (EVANS, 1932; GOGOI et al., 2016), Capila pieridoides sofa Evans,1934 distributed from Thailand to Vietnam and Capila pieridoides pieridoides (Moore, 1878) ranging from NE India and Burma (Myanmar) to Vietnam (EVANS, 1949). C. pieridoides pieridoides is the only subspecies recorded from India and is characterised by prominent orange in head extending up to the abdomen (GOGOI et al., 2016). Subspecies C. pieridoides chinensis can be distinguished from C. pieridoides pieridoides in having pointed forewing apex and a black spot at mid space 1b on upper forewing, these being absent in the latter. Subspecies C. pieridoides sofa can be distinguished from C. pieridoides pieridoides in having darker cell and veins at apex of upper forewing (EVANS, 1932; 1949).

There are few known records of C. pieridoides pieridoides from mainland India. The species was described by MOORE (1878) based on a male specimen from NE Bengal (type locality was doubtfully marked as per SWINHOE, (1911-1912)) under the genus Calliana. Later DE NICÉVILLE (1891) described female of the species from Khasi Hills based on collection of Mr. H. J. Elwes. Subsequently, SWINHOE (1893) also recorded several males and a female from Khasi hills. As per SWINHOE (1911-1912), “Elwes and Doherty record it from Margherita in Upper Assam, and Leech from China also”. EVANS (1949), in his revision of Oriental Hesperiidae listed 31 specimens from Khasi Hills, one from Manipur, one from Lushai Hills (Mizoram) and one from Ataran (Myanmar). Recently, GHOSH & CHAUDHURY (1998) listed two specimens from Khasi Hills, Meghalaya (based on material collected earlier). More recently GOGOI et al. (2016) recorded it as “very rare” in Barail Range of Cachar, Assam although it is treated as rare by EVANS (1932).

A single individual (Male) of C. pieridoides pieridoides was spotted and captured on 4^th November 2016 at 13:50 hrs from Hornbill Camp (27.538500ºN, 96.437817ºE, 658 m) of Namdapha NP (Figure 2a-b). It was found mudpuddling along the banks of a small stream with other species such as Appias nero galba (Wallace, 1867) and Appias indra (Moore, 1857). The habitat was characterized by dense canopy cover with sunlight sparsely reaching the forest floor. As we were observing the individual, a wasp (Family Vespidae) ambushed on it and killed it.

Remark: The current sighting of C. pieridoides from Namdapha is first record of this rare species from the state of Arunachal Pradesh.

Family Hesperiidae Latreille, 1809 Subfamily Hesperiinae Latreille, 1809 Tribe Aeromachini Tutt, 1906

Plastingia naga (de Nicéville, [1884])

Hesperia naga de Nicéville, [1884]. J. Asiat. Soc. Bengal, 52 (Pt II) (2/4): 89

Type Locality: “Sibsagar, Upper Assam” (India)

Distribution: NE India, Myanmar, W Malaysia, Thailand, Laos, Indonesia, Borneo and Philippines.

Genus Plastingia Butler, 1870 is widely distributed from North-east India to Sundaland, Philippines and Sulawesi, with seven species described (CORBET & PENDLEBURY, 1978; SAVELA, 2019). Two species of Plastingia Butler, 1870 are known to occur in mainland India, P. naga (de Nicéville, [1884]) and P. pellonia (Fruhstorfer, 1911) (KEHIMKAR, 2016). Previously P. pellonia was considered a synonym of P. naga (EVANS, 1932) but was removed from synonymy by EVANS (1949) based on external morphology and genital structure. P. naga (de Nicéville, [1884]) is one of India’s poorly known species of Plastingia group (DAS et al., 2016). P. naga can be distinguished from P. pellonia in having white under hindwing markings instead of yellow (EVANS, 1949). It is a widely distributed species that occurs from North-east India to Philippines (EVANS, 1932, 1949). Earlier it was known only from India (Assam) from a total of eleven male and five female specimens (EVANS, 1949). P. naga was described from Sibsaghar (upper Assam) by DE NICÉVILLE (1884) as Hesperia naga. Later, in 1912-1913 a few samples were collected by Moore & Swinhoe from Khasi and Jaintia hills, Meghalaya. The species was not recorded for next 100 years from mainland India. On October 2014, a solitary individual was recorded from central Assam (DAS et al., 2016). Subsequently, it was recorded from South Garo Hills in 2015 (KARMAKAR, 2019) and again in the same year from Barail Range, Assam (GOGOI et al., 2016). However, this species is rare in North-east India (EVANS, 1932).

On 20^th October 2016, at 14:15 hrs a single individual of P. naga was spotted near Noah Dehing Riverbed, Deban (27.497467ºN, 96.394267ºE, 350 m) of Namdapha NP (Figure 3a). The individual was mudpuddling along a small stream adjacent to a densely vegetated patch into which it flew away after few minutes.

Remark: The present sighting of P. naga from Namdapha adds a rare species to butterfly fauna of state of Arunachal Pradesh.

Family Hesperiidae Latreille, 1809 Subfamily Hesperiinae Latreille, 1809 Tribe Aeromachini Tutt, 1906

Salanoemia noemi (de Nicéville, 1885)

Plastingia noemi de Nicéville, 1885. J. Asiat. Soc. Bengal, 54 (Pt. II) (2): 120

Type Locality: “Sikkim” (India)

Distribution: Sikkim to NE India, Thailand, Vietnam.

ELIOT (1978) split the genus Plastingia into four genera, namely Plastingia Butler, 1870, Salanoemia Eliot, 1978, Pemara Eliot, 1978 and Pyroneura Eliot, 1978 (CORBET & PENDLEBURY, 1978). The genus Salanoemia can easily be differentiated from rest of the group in having rounded post discal spots and veins concolorous with ground colour (CORBET & PENDLEBURY, 1978). Salanoemia is a widely distributed genus and occurs from India to Sundaland with six known species (CORBET & PENDLEBURY, 1978; SAVELA, 2019) among which four are found in India; namely S. fuscicornis (Elwes & Edwards, 1897) (Assam and Myanmar to Borneo), S. noemi (de Nicéville , 1885) (Sikkim to NE India, Thailand and Vietnam), S. sala (Hewitson, [1866]) (Karnataka, Assam, Myanmar to Bali) and S. tavoyana titei Cantlie & Norman, 1960 (Manipur) (EVANS, 1949; VARSHNEY & SMETACEK, 2015; INAYOSHI, 2019).

Salanoemia noemi (de Nicéville, 1885) was described from Sikkim, under the genus Plastingia (DE NICÉVILLE, 1885). S. noemi differ from closely related species S. tavoyana (Evans, 1926) in having solid black spots on under hindwing compared to ring like spots of the latter. It differs from Salanoemia similis (Elwes & Edwards, 1897) another closely allied species from Malaya and Borneo (CORBET & PENDLEBURY, 1978) in having unequal cell spots on upper forewing compared to lack of cell spots or presence of a tiny dot in S. similis (EVANS, 1949). S. noemi was recently recorded from Kaziranga by GOGOI (2009). Subsequently there haven’t been any report of the species from India. As per de Nicéville, the species appears to be rare and flew from May to August (DE NICÉVILLE, 1894).

A single individual of S. noemi was photographed on 21^st October 2016 near Deban (27.497150ºN, 96.391117ºE, 345 m) along Miao-Vijoynagar road (Figure 4). The individual was sighted at 09:00 hours, basking on a rock about 0.5 m above the ground. The site was characterized by dense canopy cover with sunlight barely reaching the ground.

Remark: First record of the species from Arunachal Pradesh and extends the known distribution range of the species by at least 200 km.

Family Hesperiidae Latreille, 1809 Subfamily Hesperiinae Latreille, 1809 Tribe Aeromachini Tutt, 1906

Lotongus sarala (de Nicéville, 1889)

Parnara sarala de Nicéville, 1889. J. Bombay Nat. Hist. Soc., 4(3): 173

Type Locality: “Khasi Hills” (Meghalaya, India)

Distribution: NE India.

Genus Lotongus Distant, 1886 is mostly confined to lowland forests of Indo-Malayan region and is represented by 3 species (SAVELA, 2019). Among these, Lotungus sarala (de Nicéville, 1889) is the only species that occurs in India (EVANS, 1949). L. sarala is very similar to Lotongus avesta (Hewitson, 1868) but can be distinguished from each other based on eye colour which is black in L. sarala whereas brownish red in L. avesta (CORBET & PENDLEBURY, 1978). L. sarala (de Nicéville, 1889) is represented by four subspecies: Lotungus sarala sarala (de Nicéville, 1889) (Northeast India), Lotungus sarala conjuncta Evans, 1932 (North Myanmar), Lotungus sarala chinensis Evans, 1932 (Myanmar, Thailand, Laos, China and North Vietnam) and Lotungus sarala quinque punctata Joicey & Talbot, 1921 (Hainan) (EVANS, 1949; VARSHNEY & SMETACEK, 2015). L. sarala sarala differs from L. sarala chinensis and L. sarala quinquepunctata in having a yellow central band on upper hindwing, this being white in L. sarala chinensis and pale obsoleted in L. sarala quinquepunctata (EVANS, 1949). It differs from L. sarala conjuncta in having conjoined cell spots and spots in space 2 and 3 being overlapped whereas these spots are separate in L. sarala conjuncta (EVANS, 1949).

The species was described based on a female specimen under genus Parnara Moore, [1881] (as Parnara sarala) from Khasi hills by DE NICÉVILLE (1889). Later, SWINHOE (1912-1913) described the male specimen also from Khasi hills and regarded it as rare. Tytler reported it from Gasapani (current name Medziphema), Naga Hills and noted it as very rare (TYTLER, 1915b). After these earlier records, it was not reported from India for a long time. Recently L. sarala sarala was photographed from Neora Valley National Park, Darjeeling, West Bengal in 2010 (SARKAR et al., 2019) and from Panbari Reserve Forest, Central Assam (GOGOI, 2013). GOGOI (2013) stated that the species was sighted around 20 times during the study period and is not a rare butterfly in Panbari Reserve Forest. However, this species is regarded as rare by EVANS (1932).

On 6th October 2016 at 14:05 hrs, a single individual of L. sarala sarala was sighted near 10^th mile (27.502367ºN, 96.331517ºE, 319 m), Namdapha NP (Figure 5). The weather was sunny, and the individual was seen resting on ground along Miao-Vijoynagar road. After few minutes, it flew into dense forest surrounding the area.

Remark: This sighting of L. sarala sarala is first record of the species from Arunachal Pradesh. It also extends the known distribution range of this species to South east Arunachal Pradesh, at least 200 km away from its previous locality records (in Assam and Nagaland).

Family Pieridae Swainson, 1820 Subfamily Pierinae Swainson, 1820 Tribe Pierini Swainson, 1820

Pieris naganum (Moore, 1884)

Mancipium naganum Moore, 1884. J. Asiat. Soc. Bengal, 53 (Pt. II) (1): 45

Type Locality: “Naga Hills, Assam” [Nagaland, India]

Distribution: NE India, N Myanmar.

The Holarctic genus Pieris Schrank, 1801 is widely distributed across Himalayan region and Northeast India with 10 species known from India (MANI,1986; VARSHNEY & SMETACEK, 2015) among which Pieris naganum (Moore, 1884) is restricted to Nagaland within the country (VARSHNEY & SMETACEK, 2015). P. naganum was described based on a single male specimen from Naga Hills under the genus Mancipium Hübner, [1806] (MOORE, 1884). There are four subspecies of P. naganum, namely, Pieris naganum naganum (Moore, 1884) (Nagaland, N. Burma), Pieris naganum cisseis (Leech, 1890) (China), Pieris naganum karumi (Ikeda, 1973) (Taiwan) and Pieris naganum pamsi (Vitalis de Salvaza, 1921) (N. Thailand, Laos, Vietnam) (INAYOSHI, 2019; SAVELA, 2019). P. naganum naganum has a broad black band at apex of upper forewing; the inner border of which is slightly curved and more regular compared to other subspecies and narrowing at vein 3 (MOORE, 1884; TALBOT, 1939). After description, the subspecies has only been recorded from Sadon, N. Myanmar, based on Watson’s collection of a male specimen (MOORE, 1903-1905). This subspecies is treated as very rare by EVANS (1932) and as one of the rarest of Indian butterflies by TALBOT (1939).

On 21^st October 2016, more than 10 individuals of P. naganum were observed near 27^th Mile (27.48916ºN, 96.44388ºE, 370 m), Namdapha NP (Figure 6a). They were seen mudpuddling near an open fast-flowing stream, along with other species of butterflies such as Appias lyncida eleonora (Boisduval, 1836), Cepora nadina (Lucas, 1852), Cyrestis thyodamas Boisduval, 1846, Caleta elna noliteia (Fruhstorfer, 1918) and Prosotas nora (C. Felder, 1860) (Figure 6b).

Remark: P. naganum naganum has never been seen in at least 111 years, prior to the present record. The sighting of P. naganum naganum from Namdapha is only third record of the subspecies from anywhere in the world and the photographs presented (Figure 6) are first ever photographs of live individuals. It also extends the known distribution range of the species further North and is at least 200 km away from closest known locality (Naga hills)

Family Nymphalidae Rafinesque, 1815 Subfamily Satyrinae Boisduval, 1833 Tribe Satyrini Boisduval, 1833

Erites falcipennis Wood-Mason & de Nicéville, 1883

Erites falcipennis Wood-Mason & de Nicéville, 1883. Butts India Burmah Ceylon, 1(2): 237

Type Locality: “Cachar” (Assam, India)

Distribution: NE India, Myanmar, Thailand, Laos, Vietnam.

Erites Westwood, [1851] is a relatively small Indo-Malayan genus represented by five species, (MARSHALL & DE NICÉVILLE, 1882-1883) viz. Erites angularis Moore, 1878 (Myanmar to Sumatra); Erites argentina Butler, 1868 (Malaya Peninsular, Java, Sumatra, Borneo); Erites elegans Butler, 1868 (Malaya Peninsular, Sumatra, Borneo); Erites falcipennis Wood-Mason & de Nicéville, 1883 (India to Vietnam) and Erites medura (Horsfield, [1829]) (Myanmar, Thailand, Laos, Malaya Peninsular, Java) (SAVELA, 2019). Among these only Erites falcipennis Wood-Mason & de Nicéville, 1883 is known from mainland India (EVANS, 1932). E. falcipennis was described based on a male specimen, from Wood-Mason’s collection from Cachar, Assam, India (WOOD-MASON & DE NICÉVILLE, 1883). Its distribution ranges from Assam in India to Myanmar, Thailand, Laos and Vietnam (INAYOSHI, 2019). It differs from closely allied species in having a prominent falcate shaped forewing (EVANS, 1932). According to MARSHALL & DE NICÉVILLE (1882-1883), E. falcipennis “appear to be local but not common even where they occurred”. EVANS (1932) also considered it as rare and the species is protected under Schedule II of Indian Wildlife (Protection) Act, 1972.

On 24^th December 2017 at 10:30 hrs, two individuals of Erites falcipennis were observed (Figure 7) near 19^th Mile (27.477750ºN, 96.401200ºE, 467 m), Namdapha NP. They were resting along the road at an open and sunny spot. Occasionally, they flew close to the ground in a peculiar erratic manner.

Remark: The current sighting is first record of the species from India after its description from Cachar, Assam in 1883 and hence confirms its presence in the country. It also extends the known distribution range of the species further North, at East 400 km from Cachar, its closest previously recorded locality.

Family Nymphalidae Rafinesque, 1815 Subfamily Satyrinae Boisduval, 1833 Tribe Satyrini Boisduval, 1833

Coelites nothis adamsoni Moore, 1891

Coelites adamsoni Moore, 1891. Lep. Ind., 1: 229-230

Type Locality: “Bhamo, Burma” [Myanmar]

Distribution: NE India, Myanmar, N. Thailand (?).

Coelites Westwood, [1850] is a small Indo-Malayan genus (MARSHALL & DE NICÉVILLE, 1882-1883) with 3 species, namely Coelites nothis Westwood, [1850] (NE India to N. Vietnam, Hainan); Coelites epiminthia Westwood, [1851] (S. Myanmar to Borneo); Coelites euptychioides C. & R. Felder, [1867] (Peninsular Malaya, Sumatra) (SAVELA, 2019). Coelites nothis Westwood, [1850] has four subspecies namely, Coelites nothis adamsoni Moore, 1891 (India, Myanmar, N. Thailand (?)), Coelites nothis nothis Westwood, [1850] (Burma, Thailand, Laos), Coelites nothis sylvarum Fruhstorfer, 1902 (N. Vietnam) and Coelites nothis hainanensis Gu, 1994 (Hainan) (SAVELA, 2019).

Coelites nothis adamsoni Moore, 1891 was described based on the collections of Major Adamson from Bhamo in Myanmar. According to MOORE (1891), C. nothis adamsoni is a shade loving forest species and generally flew in the month of September and October. Its distribution ranges from Nagaland (in India) to Myanmar (EVANS, 1932; SAVELA, 2019) along with two doubtful records from N. Thailand (INAYOSHI, 2019). C. nothis adamsoni is very close to C. nothis nothis in appearance but smaller in size (MOORE, 1891). It also differs from the nominotypical subspecies in having more prominent, distinct and narrower discal and marginal lines on underside of both wings (MOORE, 1891). The subspecies adamsoni is treated as very rare (EVANS, 1932) and is also protected under Schedule I of the Indian Wildlife (Protection) Act, 1972.

A single individual of C. nothis adamsoni was spotted (Figure 8) along the roadside near Anamika waterfalls (27.493383ºN, 96.378067ºE, 413 m), Deban on 10th October 2016 around 12: 10 hrs. It was seen perched on a shrub in an area with dense canopy cover.

Remark: Apart from two doubtful records from North Thailand (INAYOSHI, 2019), C. nothis adamsoni has never been seen in last 125 years since its description. The sighting of C. nothis adamsoni from Namdapha is only second record of the subspecies from India and the photographs presented (Figure 8) are first ever photographs of live individuals.

Family Nymphalidae Rafinesque, 1815 Subfamily Limenitidinae Behr, 1864 Tribe Adoliadini Doubleday, 1845

Bassarona durga splendens (Tytler, 1915)

Dophla durga splendens Tytler, 1915. J. Bombay Nat. Hist. Soc., 23: 504

Type Locality: “Foot of the Hills on the Ukral Road, about 28 miles east of Imphal” (Manipur, India)

Distribution: NE India (Arunachal Pradesh, Manipur, Nagaland)

Genus Bassarona Moore, [1897] is widely distributed from India to Sundaland and Philippines and is represented by eight species. Out of these, four species are known to occur in India and are primarily restricted to North-eastern part of the country with just one species, Bassarona teuta teutoides (Moore, 1877) distributed up to Andaman Islands (CORBET & PENDLEBURY, 1978; SAVELA, 2019). Bassarona durga (Moore, [1858]) can clearly be distinguished from its congeners in having outwardly black edged white discal band. The species has two subspecies viz. and Bassarona durga durga (Moore, [1858]) and Bassarona durga splendens (Tytler, 1915) (EVANS, 1932).

B. durgasplendens was described based on a single male specimen collected near Imphal (Manipur) (YOKOCHI, 2010). B. durga splendens is recorded from Nagaland and Manipur, whereas nominotypical B. durga durga ranges from Sikkim to Arunachal Pradesh (EVANS, 1932). The subspecies B. durga splendens differs from B. durga durga in having a complete series of blue lunule marking on the outer edge of discal band of upper hindwing (TYTLER, 1915; EVANS, 1932). There are very few published records of the species from India. Recently it was recorded from Kuwari in Chizami, Nagaland (NARO & SONDHI, 2014). The subspecies splendens is legally protected under Schedule I of the Indian Wildlife (Protection) Act, 1972. It is noted as a very rare species by EVANS (1932).

A single individual of Bassarona durga splendens was photographed on 1^st November 2016 at 09:00 hrs near Hornbill camp (27.538500ºN, 96.437817ºE, 658 m), Namdapha NP (Figure 9). The individual was observed basking on small shrubs near to the ground.

Remark: The current sighting of B. durga splendens from Namdapha, extends its known distribution range by at least 150 km and is first record for the state of Arunachal Pradesh.

Most of the sightings detailed above are northern most distribution records of the species/subspecies studied. Species tend to occur in lower abundances at their range limits (SAGARIN & GAINES, 2002). This is perhaps why the species/subspecies recorded in the current study are rarely encountered in Namdapha and other parts of Eastern Himalayas and North east hills. Two of them namely, Coelites nothis adamsoni and Bassarona durga splendens are protected under schedule I and Erites falcipennis under Schedule II of Indian Wildlife (Protection) Act, 1972 while others are not protected legally in India. Rarity (with respect to abundance) and limited range of distribution of these species within the country warrants the need for legal protection. Forests of Namdapha NP is considered as the northern limit of lowland evergreen tropical rainforests in the world (PROCTOR & HARIDASAN, 1998). The forests here are largely intact compared to other regions of North east India and probably act as a refugia for forest butterfly species with Indo-Chinese and Malayan affinities at their range periphery. Thus, Namdapha National Park may not only be a significant Protected Area for mammals and others charismatic vertebrates but also for lesser known invertebrates like butterflies in north eastern extremity of the country.

Agradecimientos

The field work leading to the present findings was part of the project entitled “Biodiversity Assessment through Long-term Monitoring Plots in Indian Himalayan Landscape” (Grant No: NMHSLG2016/0011/8509, Dated 31.03.2016) funded by the Ministry of Environment, Forest and Climate Change (MoEF&CC), Government of India and sanctioned to Zoological Survey of India (ZSI) and Botanical Survey of India (BSI) by National Mission on Himalayan Studies (NMHS). Authors are grateful to the funding agency for providing financial support. We would like to thank Arunachal Pradesh Forest Department and forest officials and staff of Namdapha National Park, Changlang, Arunachal Pradesh for providing logistic support and necessary permits for conducting the study. We express our sincere thanks to Dr. Gopinathan Maheswaran (ZSI) for his various help during field. We are especially thankful to Mr. Tajum Yumcha, Research Officer, Namdapha Tiger Reserve and field assistant Mr. Atum Rumdo for facilitating the field work. We would also like to acknowledge Dr. Krushnamegh Kunte, Dr. Song-Yun Lang, Monsoon Jyoti Gogoi and Paul Van Gasse for their valuable inputs and encouragement. Authors are indebted to fellow researchers of the project Dr. Jagdish Saini, Dr. Hirdesh Kumar and Mr. S. K. Sajan. We would also like to thank Mr. Lokesh Mahato, Mr. Amit Gogoi, Mr. Sumit Gogoi, Mr. Wangda Drukpa, Mr. Sonam Rangpo for their valuable assistance in field.

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Author notes

*Autor para la correspondencia / Corresponding author gaurab68nandidas@gmail.com