Athyma inara sahyadriensis Kunte, 2024

Kunte, Krushnamegh & Basu, Dipendra Nath, 2024, Two new taxa of brush-footed butterflies (Lepidoptera: Nymphalidae) from the Western Ghats biodiversity hotspot, southern India, Zootaxa 5543 (3), pp. 343-367 : 356-363

Athyma inara sahyadriensis Kunte ssp. nov.

Holotype ( Fig. 7 ): Voucher code IBC-PS982 . ♂. Near Kannur , Kannur District, Kerala, India (lat-long: approx. 11.94 N, 75.765 E). Approx. 50–100 m asl. Evergreen forest. Raised from a caterpillar collected from Glochidion sp. ( Phyllanthaceae ) by Saji K., eclosed and pinned dry on 2013/03/08 by Krushnamegh Kunte. Deposited in the Biodiversity Lab Research Collections at NCBS.

Description ( Fig. 7 ):

Forewing length: 29 mm. Length of antenna: 17 mm. Head black. Eyes pale grey, spotted dark brown (eyes turn dark brown or black upon preservation). Antennae black. Proboscis grey-brown. Thorax black above with two very faint, diffused white or pale grey spots; white below. Abdomen black above with white bands on the first two abdominal segments; white below. Legs pale greyish-white.

Dorsal side: Forewings black.A very narrow, faint, diffused white line from the base to the centre of discal cell, and a large white spot at the end of discal cell. Large white spots stacked in line in interspaces 1a, 1b and 2, and then again in interspaces 4–6. A very small, diffused pale greyish-white spot in interspace 3. Dark orange subapical spots in interspaces 4 and 5, with very small, inconspicuous spots in 3 and 5. An inconspicuous, diffused, pale grey submarginal line running parallel to termen, separated from a similar line that continues from the orange subapical spots to dorsum. Hindwings black. A white band from the base through the cell to v6, the spots in 7 separated by the grey and black v7. A narrow, orange post-discal band interrupted by black veins from interspaces 1c to 7, its edges smooth, straight, not prominently convex. An inconspicuous, diffused, pale grey submarginal line running parallel to termen, from tornus to apex.

Ventral side: Forewing tawny with grey and white markings that are similar to those on the dorsal side, and with additional black smudges surrounding the white spots. Basal line through the discal cell is broader and grey, and conspicuous (rather than narrow, white and inconspicuous, as on the dorsal side). Hindwing grey post-discal band (corresponding to the narrow, orange post-discal band on dorsal side) is continued from interspace 1b to 4, but not beyond. HW submarginal grey specks between the veins.

This is a dry season form, in which UNH areas between the discal white band and post-discal grey band are plain, with dark reddish, highly diffused spots barely visible between the two bands (these spots are black and very prominent in the wet season form; see paratype IBC-AK310).

Paratypes, and intraspecific variation ( Fig. 7–9 )

♂: voucher code IBC-AK310 . Forewing length: 32 mm. Length of antenna: 17 mm. Ponmudi , Thiruvananthapuram District, Kerala, India. Approx. 1,000 m asl. Raised from a caterpillar collected from Glochidion sp. ( Phyllanthaceae ) by roadside in a tea estate by Baiju K., eclosed and pinned on 2014/02/15 by Krushnamegh Kunte. Legs preserved in 100% molecular-grade ethanol. Deposited in the Biodiversity Lab Research Collections at NCBS.

♀: voucher code IBC-PS983 . Forewing length: 32 mm. Length of antenna: 17 mm. Collection and preservation details same as the holotype, except that legs and thoracic muscle tissue are preserved in 100% molecular-grade ethanol. Deposited in the Biodiversity Lab Research Collections at NCBS. This paratype is also treated as an allotype.

♀: voucher code IBC-AY231 . Forewing length: 31 mm. Length of antenna: 17 mm. Near Periyar , Idukky District, Kerala, India. 800 m. Evergreen forest. Preserved dry, with legs and thoracic muscle tissue preserved in 100% molecular-grade ethanol. Collected on 2016/10/20 by Kalesh Sadasivan, pinned on 2016/11/20 by Krushnamegh Kunte.

Paratypes reveal considerable sexual and seasonal variation. IBC-AK310 is a wet season form in which UNH areas between the discal and post-discal white bands have large black spots, and UNF discal cell has all markings white (rather than grey as seen in the holotype). In this specimen, UPF a spot in interspace 3 is still small but much more prominent because it is white and clearly defined (cf holotype), and UPH the post-discal orange band is narrower but darker, diffusing out towards apex.

Female paratypes are black on the dorsal side with orange markings as follows: Forewing: (a) a streak from base through the discal cell up to the large cell-end spot from which it is separated by a narrow black line (more prominent in the allotype), with a smaller spot beyond the discal cell (this spot is more elongated with a narrow point in IBC-AY231), (b) on both wings, post-discal and subapical bands similar to the males but the bands are much broader and pale yellowish-orange in colour (rather than narrower and white or dark orange as in males). Females have a single narrow white band on the first abdominal segment (two broader, more prominent white bands in males).

Ventral side: Yellowish-orange with paler bands that correspond to the bands on dorsal side, with black smudges in the areas adjacent to the bands. IBC-PS983 is an intermediate seasonal form in which the bands barely stand out on the wing background, and UNH black discal spots are small. In the true dry season form, the bands are even more inconspicuous, and the black post-discal spots are absent. IBC-AY231 is a wet season form in which the pale bands are prominent, and the black post-discal spots are prominent.

Genitalia ( Fig. 8 ): Male (IBC-PW982): Very similar to the genitalia of A. i. inara , from which it differs primarily in having a smaller costal process/style. Tegumen large, broad. Uncus straight, slightly curved down at the tip. Gnathos slightly narrower than that of A. i. inara . Valve narrow, long, pointed, hairy. Phallus short, stout, ending in a sharp point.

Diagnosis ( Fig. 9–10 ): The diagnosis of this subspecies was briefly outlined by de Nicéville (1886) under Athyma inarina based on a single male specimen from Wynaad (N Kerala) that was available to him at the time, although he did not taxonomically name it. A combination of 10 characters in male readily and consistently differentiates A. i. sahyadriensis ssp. nov. from related taxa ( Fig. 10 , in which numbered pointers correspond to the following numbered characters): (1) UPF prominent subapical orange markings, which distinguish it from A. nefte ; (2) UPF no orange or white markings below the subapical orange markings, only two inconspicuous, diffused grey lines (orange line or spots prominent in A. i. inara , especially with a larger spot in interspace 3; lines prominent grey or white in A. nefte ); (3) UPF white post-discal spot in 3 smaller, less conspicuous (this spot is larger and more conspicuous in A. i. inara , absent or almost absent in A. nefte ); (4) UPF white line through the discal cell very narrow, inconspicuous (sometimes entirely absent), not connecting with the large white spot at the cell-end (the line usually more prominent and longer, powdery-grey or white, connecting with the white cell-end spot in A. i. inara ; very prominent, white and connecting with the much larger and more prominent cell-end spot in A. nefte ); (5) UPH post-discal band narrow with even edges, dark orange (this band much broader, paler orange, with the inner edges of the spots that comprise this band being prominently convex in A. i. inara ; band white and narrow in A. nefte ); (6) UNF streak through the cell grey or white, more prominent than on dorsal side (this streak similar to A. i. inara ; it is much more white, broader and conspicuous in A. nefte ); (7) UN wing colour orange (colour orange-brown in A. i. inara ; brown without a trace of orange in A. nefte ); (8) UNF submarginal markings grey and inconspicuous, or absent (these markings especially prominent in interspaces 1–3 in A. i. inara ; and narrower but from 1–7 in A. nefte ); (9) UNF outer edge of the large white spot in 2 protrudes out from the spot in 1b but it protrudes less than the width of the two grey submarginal lines/small spots (this spot similar in A. i. inara ; it protrudes much more, i.e., more than the width of the submarginal white lines in A. nefte ); (10) UNH narrow, grey or white post-discal band ends in interspace 4 (this band is broader and it extends up to the apex in A. i. inara ; it is much much whiter but narrower in A. nefte ). Additionally, A. i. sahyadriensis ssp. nov. differs from A. i. inara and A. nefte in having a narrower, more produced forewing.

Athyma asita , whose taxonomic status needs to be carefully examined with a separate molecular phylogenetic study (see under Discussion), differs from A. i. sahyadriensis ssp. nov., A. i. inara and A. nefte , in having: (a) UPF submarginal markings prominent and white, especially the large spot in interspace 3 (this large spot and other submarginal markings are orange in A. i. inara ; they are white or pale grey, much narrower but prominent, and without a large spot in interspace 3, in A. nefte ; they are absent in A. i. sahyadriensis ssp. nov.), (b) UPH post-discal band narrow, white (orange in A. i. inara and A. i. sahyadriensis ssp. nov.; similar in A. nefte ), (c) FW discal cell with a well-defined white line that is well-separated from the white cell-end spot, with another white spot beyond the cell-end that is almost as large (these markings are highly reduced in A. i. sahyadriensis ssp. nov.; conspicuous but diffused in A. i. inara ; much more prominent with a much larger cell-end spot in A. nefte ), and (d) UN brown with a slight tinge of orange (brighter orange-brown in A. i. sahyadriensis ssp. nov. and A. i. inara ; darker brown without a tinge of orange in A. nefte ).

Females are similar to A. i. inara , from which they apparently cannot be distinguished. They differ from females of A. nefte in having considerably broader orange markings UP, and brighter orange UN (UP markings narrower, UN background colour of the wings brown, not orange).

Etymology: We name Athyma inara sahyadriensis ssp. nov. after its endemic distributional range in the Sahyadri, the name of the Western Ghats in many native languages.

Historical Records: This taxon is well-documented in the Western Ghats based on hundreds of records (also see Fig. 12 ). Evans (1932) used the name Pantoporia nefte inara , recording it as “S. India, Sikkim —N. Burma. NR [Not Rare].” According to Wynter-Blyth (1957), who referred to it as Pantoporia nefte , “ Range. South India. Sikkim to Assam and South Burma. … Recorded as not rare in the evergreen regions of the Western Ghats, also, very rarely, from the Mettupalaiyam Ghat in the Nilgiris.” Talbot (1947) did not cover the genus. d’Abrera (1985) mentioned “ Nepal to Assam ” as the range of A. nefte inara , with range in the Western Ghats as doubtful, “? southern India ”.

The NHMUK has 8 ♂ and 8 ♀ specimens (four of each sex photographed and catalogued, see Materials and Methods) from Karwar, Karwar District, Karnataka, raised from early stages by T. R. Bell in 1920s, except: one male from “Malabar, Wynaad” from “Moore Coll. 99-234”, one male from “Nilgiris 89-53 5,000 ft ”, one female from “Nilgiris 89-53 3,000 ft ”, and one male from “Watecolle [Kerala] 16/11/60 [1960]” and one female from “Sollekolle 14/10/60” from A. J. Sharman Collections, which did not have voucher codes. MCZ and McGuire Centre for Lepidoptera and Biodiversity do not have any specimens of the new subspecies.

Species Biology and other Notes

Distribution: Athyma inara sahyadriensis ssp. nov. is distributed almost throughout the Western Ghats, from Shendurney WLS in southern Kerala to Phansad WLS, Raigad District ( Bhopale & Athavale 2009), and Tamhini, Pune District, in northern Maharashtra ( Fig. 12 ). In comparison, A. i. inara occurs in NE India and N Myanmar, A. asita (often treated as a subspecies of A. nefte , see Discussion) occurs throughout Indo-China (except S Thailand) and S Myanmar, extending northward into S China, and A. nefte occurs from S Thailand to Malaysia, and Indonesia from Java to Borneo ( Fig. 12 ), in subtly different subspecific variations.

Status, habitat, and habits: Athyma inara sahyadriensis ssp. nov. occurs in low-lying evergreen forest patches (usually below 700–800 m asl), where it may be seasonally and locally not uncommon along shaded forest streams and forest edges. Males are encountered mud-puddling, or feeding on carnivore scats and rotting crabs, usually on the ground. Females tend to stay on vegetation, often feeding on bird droppings. They have not been observed feeding on flower nectar. Other habits are similar of the genus.

Flight period: Athyma inara sahyadriensis ssp. nov. is multivoltine, flying throughout the year, with a population peak from October to January ( Kunte et al. 2024).

Larval host plants and early stages: The following larval host plants are known for A. inara sahyadriensis ssp. nov.: Glochidion lanceolarium , G. heyneanum , G. zeylanicum ( Phyllanthaceae ), and Mussaenda frondosa ( Rubiaceae ) ( Nitin et al. 2018). The early stages are well-documented ( Bhakare & Ogale 2018; Saji et al. 2024), and also illustrated here ( Fig. 11 ).

Sympatric Athyma : The following Athyma occur in the Western Ghats along with A. inara sahyadriensis ssp. nov.: Athyma p. perius (Linnaeus, 1758) , Athyma ranga karwara Fruhstorfer, 1906 , and Athyma selenophora kanara (Evans, 1924) . Athyma perius normally occurs on open ridge-tops and plateaus, not in the shaded evergreen forest habitats as A. inara sahyadriensis ssp. nov., but A. ranga and A. selenophora may occur side-by-side with A. inara .

Further information will be made available on the species page of the Butterflies of India website (https://www. ifoundbutterflies.org/ Athyma ) as additional observations accumulate.

Figures

FIGURE 7. Type specimens of Athyma inara sahyadriensis ssp. nov. A millimetre scale is at the bottom. Photographs: Dipendra Nath Basu, Ujwala Pawar, and Krushnamegh Kunte.

FIGURE 8. Male genitalia of Athyma inara sahyadriensis ssp. nov. (holotype, IBC-PW982) and A. i. inara. Photographs: Dipendra Nath Basu.

FIGURE 9. Comparison of Athyma inara sahyadriensis ssp. nov. with other similar Athyma (see Materials and Methods for specimen details). A millimetre scale is at the bottom. Photographs: Krushnamegh Kunte.

FIGURE 10. Diagnostic characters of Athyma inara sahyadriensis ssp. nov., marked on digitally enhanced images from which wing-wear has been removed to illustrate the distinctive phenotype of the subspecies. Male of A. i. sahyadriensis ssp. nov. is compared with males of A. i. inara and two subspecies of A. nefte. Numbers point to distinctive characters: 1: FW subapical markings, 2: FW submarginal markings, 3: FW spot in interspace 3, 4: FW markings in the discal cell, 5: HW post-discal band, 6: UNF markings in the discal cell, 7: UN base colour of the wings, 8: UNF submarginal markings, 9: large white spot in interspace 2, 10: UNH post-discal band (further details in the text). Images are not to scale. Photographs: Krushnamegh Kunte.

FIGURE 11. Early stages of Athyma inara sahyadriensis ssp. nov. a: egg (2010/11/05); b: 1st instar (2010/09/20); c: 2nd instar (2010/09/26); d–e: 3rd instar (2010/10/02); f–i: 4th instar (2010/10/05–07); j–l: 5th instar (2010/10/08); m–n: 5th instar with colours changed just before pupation (2010/10/10). o–q: newly-formed pupa (o: lateral view; p: dorsal view; q: ventral view); r–s: pupa before eclosion (r: lateral view; s: dorsal view); t: eclosed female resting on pupal case, drying its wings. Images are of multiple individuals. Amboli, Sindhudurg District, Maharashtra, India. Photographs: Hemant Ogale, used with permission.

FIGURE 12. Distributional range map of relevant taxa from the Athyma nefte species group. Pink: A. inara sahyadriensis ssp. nov., blue: A. i. inara, Purple: A. asita, Yellow: A. nefte. Map: Viraj Nawge.