Thursday, December 12, 2024

Life history of Hypolycaena othona - Orchid Tit

Life history of Hypolycaena othona - Orchid Tit

- Nitin Kawthankar (2024)

Life history of Orchid Tit ©️Nitin Kawthankar

Butterfly Biodata:
Butterfly: Orchid Tit
Species: Hypolycaena othona Hewitson, [1865]
Subspecies: H. othona othona Hewitson, [1865]
Classification: Lycaenidae: TheclinaeHypolycaenini
Wingspan: 24-27 mm
Distribution: Oriental (India to Indonesia)
Larval host plants: Epiphytic orchids (Orchidaceae)

Introduction:
     The genus Hypolycaena is represented by two species in the Western Ghats: H. nilgirica and H. othona, with the former being endemic to the southern Western Ghats and Sri Lanka. In contrast, the Orchid Tit (H. othona) exhibits a broader distribution, ranging from India (Western Ghats, East India, Himalayas, Northeast India & Andaman & Nicobar Islands) to Indonesia (Fiedler, 1992; Butterflies of India, 2024; iNaturalist, 2024; Sethumadhavan et al. 2024). This species typically inhabits moist forested areas where its host plant, orchids, are present.
     The taxonomic placement of the Orchid Tit within Hypolycaena has been questioned, with some authors supporting its old classification as Chliaria (Fiedler, 1992; Sawant et al., 2016; Bhakare & Ogale, 2018). The life history of the Orchid Tit has been well-documented in previous studies (Davidson et al., 1896; Bell, 1915; Fiedler, 1992; Sawant et al., 2016; Bhakare & Ogale, 2018; Butterflies of India, 2024).

Larval Host Plants:
1. Acampe praemorsa (Orchidaceae) - Brittle Tiger Orchid, वाघरी
2. Aerides crispa (=A. crispum) (Orchidaceae) - Curled Aerides, पानशिंग
3. Aerides maculosa (Orchidaceae) - Fox Brush Orchid, ठिपके इरीड आमरी
4. Cottonia peduncularis (Orchidaceae) - Bee Orchid, भ्रमरी
5. Rhynchostylis retusa (Orchidaceae) - Foxtail Orchid, सीतेची वेणी
     Orchid Tit is an oligophagous species, feeding exclusively on floral parts of epiphytic orchids from the family Orchidaceae (Nicéville, 1900; Bell, 1915; Wynter-Blyth, 1957; Sawant et al., 2016; Nitin et al., 2018; Butterflies of India, 2024).
     Additionally, Veenakumari et al. (1997) recorded Papilionanthe subulata (=Thrixspermum filiforme)(Orchidaceae) from the Andaman & Nicobar Islands. Fiedler (1992) reported a ground orchid, Spathoglottis plicata (Orchidaceae), as the first non-epiphytic host plant from Malaysia.
     Orchidaceae, the second-largest plant family, is surprisingly utilized as a host plant by a single butterfly genus, Hypolycaena, in India.

Early Stages:
Eggs: Although direct observation of oviposition was not made, the egg-laying pattern could be inferred from the egg distribution. Eggs were typically laid singly on either floral buds (inflorescence buds) or seed pods. Notably, no more than two eggs were found on a single plant (n=8). Eggs were small, white and hemispherical in shape, resembling a half-cut golf ball.
1st Instar: The egg hatched after 4-5 days (n = 2). A tiny, yellowish egg-larva emerged from the egg by consuming just enough of the egg shell to emerge, leaving the remaining egg shell intact. It began feeding by boring into the floral bud or seed pod, creating a small tunnel that fitted its body exactly. Notably, a chain of frass pellets was visible around the feeding tunnel. This instar lasted 2 days, during which the larva reached a length of 3 mm (n=2).
2nd Instar: In this instar, the caterpillar acquired the colour of the plant part it fed on, i.e. green or reddish-green, and a mid-dorsal pink-red band developed, passing through all segments. The feeding behaviour was consistent with the previous instar. This instar lasted 3 days, during which the larva reached a length of 5 mm. Most caterpillars left their feeding tunnels and moulted externally on the seed pod or stem (n=2).
3rd Instar: A distinct change in this instar was the presence of two tail-like projections on the last abdominal segments ("tail-points" of Bell, 1915), which were clearly visible, projecting from the feeding tunnel. Another obvious change was that the tunnel openings were cleaner than in previous instars, with no frass remains. This instar reached a length of 9 mm and lasted 3 days (n=2).
4th Instar: The fourth and final instar caterpillars resembled the previous instar but were relatively large and prominently marked compared to previous instars. They fed voraciously, digging completely inside the pod or floral buds and nearly hollowing them out. This instar lasted 4-5 days and reached a maximum length of 16 mm (n=2).
Prepupa: On the last day of the final instar, the caterpillar underwent complete decolorisation, including the loss of its distinctive mid-dorsal pink-red band, and found a secure place for pupation on a seed pod or stem, where it rested for 1 day before pupation (n=4).
Pupa: The pupa was green in color, featuring a distinctive wavy mark near the wing pad. It was attached to the substrate in a head-down position, secured by a silk girdle and silk pad. After 1 day of pupation, the colour became slightly greyish. After 7-8 days, the wing pad area became whitish. One day prior to eclosion, the pupa became dark, with the upper wings visible through the wing pad (n=4). 
Imago: It took 10-12 days to eclose from the pupa. Adults emerged between 07:45 to 12:00 hours in the morning (n=4).
     The complete life cycle lasted approx. 26-30 days: egg (4-5 days), larva (12-15 days), and pupa (10-12 days).

Mymecophily: 
     The Orchid Tit caterpillars exhibit facultative mymecophily, as previously documented by several authors (Bell, 1915; Wynter-Blyth, 1957; Fiedler, 1992). Although various ant species (Formicidae) frequently visited the floral nectaries of the host plant, they occasionally tended to the caterpillars, indicating a non-obligate association. Caterpillars possess a functional dorsal nectary organs (DNOs) from the 3rd instar but lack a tentacular organs (TOs) (Fiedler, 1992).

Discussion:
     The above observations largely confirm previous records, with some notable differences. Notably, caterpillars possess two tail-like projections, known as tail-points, on the last abdominal segment, which become prominently visible from the 3rd instar.
     Caterpillars exhibit variability in colour, ranging from green to purple, most likely influenced by the colour of the plant part they feed on. Interestingly, they exhibit a partially endophytic feeding behavior, tunneling into host plant parts like floral buds and seed pods, while avoiding leaves, which aligns with previous studies. However, we did not observe the caterpillars feeding on open flowers or flower petals (Bell, 1915; Sawant et al., 2016; Bhakare & Ogale, 2018; Butterflies of India, 2024), stems (Fiedler, 1992), or aerial root tips (Bhakare & Ogale, 2018).
     Our observations indicate that the caterpillars have four larval instars, which agrees with Fiedler (1992) but disagrees with Sawant et al.'s (2016) record of five, and further research is needed to clarify this difference.
     The Orchid Tit shows a sharp peak in activity between November to February. In contrast, most of its recorded host plant Orchids, flower and fruit typically during the monsoon, from May to September. Further study is needed to understand how the butterfly synchronizes with its host plant phenology.
     Notably, Acampe, a single recorded host plant species, reproduces multiple times a year, with year-round flowering coinciding with the butterfly's activity peaks. This can be inferred as Acampe being the likely preferred larval host plant of the Orchid Tit in the Western Ghats.

References:
- Butterflies of India (2024): Hypolycaena othona Hewitson, [1865] - Orchid Tit. Acc. 12/12/2024.
- iNaturalist (2024): Orchid Tit (Hypolycaena othona). Acc. 12/12/2024.

- Bell (1915). The common butterflies of the plains of India, Part 17. JBNHS, 23: 481-497.
- Davidson, Bell & Aitken (1896). The butterflies of the North Kanara district of the Bombay presidency, Part II. JBNHS, 10: 372-393.
- Fiedler (1992). Notes on the biology of Hypolycaena othona (Lepidoptera: Lycaenidae) in West Malaysia. Nachr. Entomol. Vereins Apollo, 13(2): 65-92.

- Bhakare & Ogale (2018). A Guide to the Butterflies of Western Ghats (India).
- Nitin, Balakrishnan, Churi, Kalesh, Prakash & Kunte (2018). Larval host plants of the butterflies of the Western Ghats, India. JoTT, 10(4): 11495-11550. DOI: 10.11609/jott.3104.10.4.11495-11550.
- Veenakumari, Mohanraj & Sreekumar (1997). Host plant utilization by butterfly larvae in the Andaman and Nicobar Islands (Indian Ocean). Journal of Insect Conservation, 1: 235-246.
- Wynter-Blyth (1957). Butterflies of the Indian Region.

Observations & text by Nitin Kawthankar.

Saturday, December 7, 2024

First Record of Caltoris canaraica - Karwar Swift from Sindhudurg District, Maharashtra, India

First Record of Caltoris canaraica - Karwar Swift from Sindhudurg District, Maharashtra, India

- Raj Gurav & Nitin Kawthankar (2024)

Karwar Swift nectaring on Ranmodi flowers ©️Raj Gurav
Butterfly Biodata:
Butterfly: Karwar Swift or Kanara Swift
Species: Caltoris canaraica (Moore, [1884])
Subspecies: no subspecies
Classification: Hesperiidae: Hesperiinae: Baorini
Wingspan: 41 mm
Larval host plants: Bamboo (Poaceae)

The genus Caltoris Swinhoe, 1893 is represented by four species in the Peninsular India, with two species previously recorded from Sindhudurg district and Maharashtra: C. kumara (Moore, 1878) and C. philippina (Herrich-Schäffer, 1869) (Sadasivan et al., 2023; Butterflies of India, 2024).

Caltoris canaraica (Moore, [1884]) was originally described as Parnara canaraica Moore, [1884], with its type locality in the Canara region of the western coast of South India (Moore, 1884). Wynter-Blyth (1957) subsequently transferred it to Caltoris, referring to it as the Kanara Swift. Recently, it has been renamed the Karwar Swift (Butterflies of India, 2024).

Historically considered endemic to the Western Ghats and adjoining regions, C. canaraica has been recorded well outside of the Western Ghats in Peninsular India, from Goa, Karnataka, Kerala, Tamil Nadu (Butterflies of India, 2024). A single central Indian record from Nagpur, Maharashtra by Tiple & Khurad (2009) lacks photographic evidence, with no other confirmed records from Central India.

Here, we present the first record of C. canaraica from Kudal NP, Sindhudurg district, Maharashtra. A single individual was observed nectaring on 'Ranmodi' - Chromolaena odorata (Asteraceae) flowers and resting on leaves at intervals on 10 Jan 2024 at around 11:50 hrs.

This sighting represents the northernmost record of the C. canaraica from the Western Ghats and new addition to the Sindhudurg district's checklist, expanding its known distribution range northwards in the Western Ghats of Maharashtra.

References:
Butterflies of India (2024): Caltoris canaraica - Karwar Swift. Acc. 07/12/2024.
Sadasivan, Basu & Kunte (2009). A new subspecies of Caltoris Swinhoe, 1893 (Lepidoptera, Hesperiidae) from the Malabar Coast, Kerala, India. Entomon, 48(1): 1-10. DOI: 10.33307/entomon.v48i1.838.
Moore (1884). Descriptions of new Asiatic diurnal Lepidoptera. Proc. zool. Soc. Lond., 4: 534.
Wynter-Blyth (1957). Butterflies of the Indian Region.

Observations by Raj Gurav & text by Nitin Kawthankar.

Friday, December 6, 2024

First Record of Cephrenes acalle - Plain Palm-Dart from Sindhudurg District, Maharashtra, India

First Record of Cephrenes acalle - Plain Palm-Dart from Sindhudurg District, Maharashtra, India

- Nitin Kawthankar (2024)

Plain Palm-Dart (male & female) ©️Nitin Kawthankar

Butterfly Biodata:
Butterfly: Plain Palm-Dart
Species: Cephrenes acalle (Höpffer, 1874)
Subspecies: C. acalle oceanica (Mabille, 1904)
Classification: Hesperiidae: Hesperiinae: Taractrocerini
Wingspan: 40-45 mm
Larval host plants: Coconut (Cocos nucifera) & other Palms (Areaceae)

The butterfly diversity of Sindhudurg district has been well-documented, thanks to the efforts of experts like Hemant Ogale, Dattaprasad Sawant, and other naturalists from the district, as well as numerous nature enthusiasts who have visited the Amboli-Dodamarg area. The district has yielded records of over 200 species (Butterflies of India, 2024).

Cephrenes acalle is a hesperiid butterfly found in the Oriental region. It was first recorded in the Western Ghats from Kerala in 2009 (Kalesh & Prakash, 2009). Subsequent records have been reported from Tamil Nadu, Karnataka, and Goa (Butterflies of India, 2024). In Maharashtra, the species was first recorded from Mumbai City district by Shantanu Joshi in 2012, followed by records from Thane, Raigad, Pune, and Ratnagiri districts (Butterflies of India, 2024; iNaturalist, 2024).

Here's the first record of Cephrenes acalle from Pal village, Vengurla taluka, Sindhudurg district, Maharashtra (Lat: 15.841075° N, Long: 73.677931° E). The species was found in a village house and its adjacent home garden with coconut plantations. On 03 December 2022, at 22:40 hrs, a male individual was photographed resting on a Hibiscus plant at a height of 2 m. A second record was observed on 23 September 2024, at around 20:00 hrs, when a female individual entered the house and settled on wooden rafters of the roof at a height of approx. 5 m.

These sightings represent a new addition to the district's checklist and fill a gap in the distributional records of this species between Ratnagiri district and Goa state. The widespread presence of its host plant, Coconut, in the western coastal region suggests that this species is likely widespread within the district. Possibly overlooked until now due to its similarities with Telicota spp. Further observations are necessary to determine its exact extent and status in the district.

References: