Diversity of moths from the urban set-up of Valmiki Nagar, Chennai, India

and the confirmation of the moth species recorded in the study. Her inputs during the analysis of data were also extremely vital to eliminate any confirmation bias in the study. The authors would also like to thank M. Yuvan for his help in identifying the plants seen during the study and for his valuable companionship. Abstract: A study was conducted at Valmiki Nagar, Chennai, Tamil Nadu, India to explore its moth diversity from December 2018 to May 2021. This manuscript presents a partial checklist of moths from Valmiki Nagar. Four locations around the colony were studied to record the moth fauna. The study sites were surveyed twice a month using a mercury vapour lamp along with a white sheet, along with over 100 visits at night. Diurnal surveys were conducted bimonthly to observe larval host plants and day flying moths. A total of 135 species were recorded from the study area, belonging to nine superfamilies. The most diverse family of moths recorded was family Erebidae, with 39% of moths recorded in the study belonging to this family, followed by Crambidae (30%), Geometridae (8%), and other families constituting the rest. The moth diversity in the month of July was seen to be the highest. Along with this study, future studies on similar lines will help in documenting the moth diversity of Chennai.


INTRODUCTION
Moths are predominantly nocturnal and complement butterflies, their daytime counterparts, as important pollinators of flowers especially the night blooming ones (Anil & Parthasarathy 2017).
Moths play an important role in the food chain as prey for diverse organisms such as bats, birds, insects, and reptiles (Raju & Ramana 2020). Several species of moths are important ecological indicators of the ecosystem's health (Warren & Bourn 2011) due to their sensitivity to the changes in the environment and are model organisms for habitat quality and climate change. Moths are often considered as pests in agroecosystems due to the large-scale crop damage caused predominantly in their larval stages (Sinu et al. 2013) and by some species in their adult stages, like the fruit piercing moths (Eudocima spp.).
India has recorded over 12,000 species of moths across 40 families (Chandra & Nema 2007). Several studies have been conducted across various locations in southern India. A large section of the studies that were conducted in Tamil Nadu are from the ghat regions with none from urban residential set-ups. Several studies from Tamil Nadu recorded varying moth diversity, including 188 species of Noctuoidea from four families (Sivasankaran et al. 2017), five species of fruit piercing moths of the genus Eudocima (Ramkumar et al. 2010a) and 27 species of moths belonging to the family Sphingidae from Kanyakumari (Iyer & Kitching 2019). The most recently published moth diversity study at Chennai is from the Adyar Eco-Park, where 90 species of moths (Nagarajan et al. 2021) were recorded. Another study dealt with the coast of Chennai recorded 42 species (Nagarajan et al. 2022).
The current study aims at documenting the species diversity of Valmiki Nagar (Chennai), thereby giving an insight into the urban moth diversity of Chennai.

Study area
Chennai is the capital city of the state of Tamil Nadu, situated along the Coromandel coast. The mean temperature of Chennai is around 28.6 °C and it receives an annual mean rainfall of 140 cm. However, most of the rain Chennai receives is in bulk during the northeast monsoon. It also houses tropical dry evergreen forest, scrub forests, grasslands, mangroves, and sand dune habitats. This wide range of habitats is favourable for Chennai to host a variety of fauna. A total of 1,039 species of plants have been recorded in Chennai, 322 species of birds (eBird India 2020), and 18 species of mammals have also been reported from Chennai. So far, no study on the moths recorded in the whole of Chennai has been published, though several works are being pursued by the authors to shed light on the same.
Valmiki Nagar is a residential colony located in Thiruvanmiyur, Chennai, Tamil Nadu, India. Several private gardens and avenue trees growing in the neighbourhood encompass the natural vegetation of the study area. The most predominant trees (mostly non-native) in the locality are Copperpod Tree Peltophorum pterocarpum, Rain Tree Albizia saman, Neem Tree Azadirachta indica, Indian Ash Tree Lannea coromandelica, Portia Tree Thespesia populnea, Gulmohar Delonix regia, Pongame Tree Millettia pinnata, and Peepal Tree Ficus religiosa. It is a coastal colony, located along the Bay of Bengal. Thickets growing in the fringes of the beach account for species normally found in grasslands and open country. This vegetation consists of Calotropis, Devil's Grass Cynodon dactylon, and Acalypha indica. To the north lies Kalakshetra, a thickly vegetated campus that is known to house several forest fauna, including the Slender Loris (Kumara et al. 2017). Thiruvanmiyur is known to house 72 species of butterflies, with a majority of species recorded from Valmiki Nagar. Valmiki Nagar alone has 98 species of birds recorded (eBird India 2021). With such data publicly availed, the authors aim to shed light on the moth diversity of the locality.

METHODS
A preliminary survey was conducted to find suitable light trapping sites. Four sites where substantial moth diversity was observed were selected as survey sites. The locations have been marked in Figure 1. From December 2018, regular and periodic moth observations were made by setting up a moth sheet and surveying the walls of apartments in the locality.
The moth sheet has been described in the sentences that follow. A single white cloth (134 x 130 cm) was spread out between two vertical poles. Above this cloth, a 150 W power mercury vapour lamp was placed and connected to the nearest power supply. This screen was set up from 1930 h till 0030 h once every 15 days. This was done to record changes in diversity due to changes in the lunar phase, if any. Apart from the moth sheet, species visiting tube lights in common areas of the community that were easily accessible moths were also recorded. These were recorded in various staircases of apartment complexes in the community. These surveys were conducted at least twice a week to generate significant data to assess the J TT seasonality of species and moth abundance throughout the year. To maintain uniformity in data collection, the survey was conducted individually along a transect and observations were made around the same time (2030-2200 h). There are a few studies in India on the moth diversity in urban spaces. Thus, this was conducted to show the cohabitation of moths in urban landscapes. Opportunistic nocturnal walks and day walks were also carried out. Day walks were conducted to record species that were active pollinators and to find moths that might have been otherwise missed.
No live moths were collected during the study attributing to the ethical beliefs of the authors. Moths were recorded using visual observation and photographs. A Canon 5D Mark IV camera along with a 100 mm macro lens was used to photograph the moths. No external flash was used. However, in some cases, a flashlight was used to provide illumination. Identification of the various species of moths was done by comparing the external morphology of the observed moths to the descriptions provided by Hampson (1892). Consultation with experts wherever possible, references from citizen science initiatives like www.mothsofindia.org and www. inaturalist.org, and the field guide by Shubhalaxmi (2018) were made uses for identifying moths. Difficult to confirm species were left at genus level.

RESULTS AND DISCUSSION
During the defined period of observation, a total of 135 species of moths were recorded from the locality. These include 11 species belonging to the superfamily Bombycoidea, one species of Gelechioidea, 11 species of Geometroidea, one species of Hyblaeoidea, 66 species of Noctuoidea, 42 species of Pyraloidea, one species of Thyridoidea, one species of Yponomeutoidea, and one species of Tortricidae. A complete annotated checklist of moths recorded in the study can be found in Table 1. Out of these listed species, 97 of them were photographed and have been represented in Image 1-98.
Out of the 135 species of moths, 100 species were seen in Site 1, 84 species were seen in Site 2, and 36 species were seen in Site 3. Twenty-three species of moths were seen opportunistically and not during the moth screen sessions.
Moth studies on the moth diversity from Tamil Nadu are family-or subfamily-specific. The current study attempts to understand the moth diversity from various families found in the study area.
A study on Sphingid moths from Kanyakumari (Iyer & Kitching 2019), the first of its kind from the state, records 27 species of moths, of which six were recorded in the current study. Cephonodes picus was not recorded in the study at Kanyakumari, while being observed regularly at Valmiki Nagar. Both Cephonodes spp. were observed in the day. During this time, they were observed on flowers such as Alexandrian Laurel (Calophyllum inophyllum). Neolamarckia kadamba was the observed host plant for Cephonodes sp. They were seen visiting walls in hot afternoons. They were only seen in June and July in the study. In the current study, an interesting striped Hippotion moth was observed. Iyer & Kitching (2019) described Hippotion boerhavia as a difficult species to confirm based on morphology and is said to only be confirmable with genitalia examination of a male specimen; but they do mention that H. boerhavia has a more striped appearance and elongated forewing, as seen in the specimen that was recorded in our current study, eliminating it from H. rosetta, which was also seen during the study. Another similar species, H. rafflesii is known to occur in southern India, but this species is known to have a rich brown ground colour and poses a pink shaded hind wing upper side tornus (pale in the specimen dealt with in our study). This leaves us with the only other option, H. echeclus, a species known to occur in drier parts of southern India. However, this was also eliminated due to the absence of a black upper margined under wing in the specimen seen in our study. However, without a proper examination of the genitilia, it was decided to leave the specimen encountered as a Hippotion sp. Hippotion were seen nectaring and resting in the mornings on Sensieveria zylanica. Caterpillars of Hippotion sp. were seen feeding on the Pongame Tree, which also served as the host plant for Psilogramma vates. They were best seen from June till October, most commonly in the months of July and August. Caterpillars of Daphnis nerii were observed feeding on Nerium oleander. Superfamily Noctuoidea was the most diverse superfamily in the study area, with moths belonging to the family Erebidae being the most common and diverse in the study area. Subfamily Erebinae was the most diverse in this family. The most common species from the subfamily include Parallelia stuposa, Gramodes geometrica, Achaea janata, Pandesma sp., Trigonodes hyppasia, Mocis undata, Pericyma glaucinans, and Lacera noctilo. Subfamily Artcinae were infrequently observed in the study area, except Amata passalis, which was seen commonly throughout the year, especially after heavy rains. Amata passalis caterpillars were observed eating dead wood on several occasions, as well as on Millettia pinnata. Amyna axis, Helicoverpa armigera, Spodoptera litura, Pseudozarba opella, and Chrysodeixis sp. were the most commonly seen members of the family Noctuidae. Spodoptera litura catterpillars were seen on a wide variety of garden plants and weeds. The moth is known to have a wide variety of host plants according to (Jian-Xiang et al. 2011).
A detailed diversity and seasonality study on fruit piercing moths (genus Eudocima) from the state describes the presence of five species, which are usually seen from September to January (Ramkumar et al. 2010b). The current study was able to find three out of these five, with the seasonality of the species matching the trends observed by Ramkumar. In our study, E. materna had a longer on wing period among the fruit piercing moths, for almost eight months of the year, followed by E. phalonia, as was the case in Ramkumar's study. It is also noteworthy that the present study and Ramkumar's record the same relative abundance between the species, E. materna > E. phalonia > E. homaena. These moths were found mainly in the second and third floors of apartments, at a height of 20 and 30 feet from the ground, respectively. E. phalonia was often seen hovering near pomegranate plants, while E. materna was seen laying its eggs on a Citrus sp., both known host plants for the respective species (Shubhalaxmi 2018).
A study by Rathikannu in 2018 recorded 188 species of moths from this family from various locations in Tamil Nadu (Rathikannu et al. 2018), which lists most of the species seen in the current study. The most diverse subfamily recorded in the study was subfamily Spilomelinae. The most common species observed were Euclasta sp., Paliga sp., Antigastra catalaunalis, Cnaphalocrocis medinalis, Sameodes cancellalis, Spoladea recurvalis, and Pygospila tyres. During the observations made in this study, crambid moths were most common in the second floor of apartments, at an height of 6.1m (20 ft) from the ground. The most preferred season for moths from this family was from June till October. Cnaphalocrocis medinalis in particular was seen in swarms of up to 200 individuals during the month of October. Cydalima laticostalis was the only observed exception, only seen in the study area from November to March. Among the rare species,    (Lang et al. 2011). Two species of micromoths were commonly recorded in the study, namely, Plutella xylostella and Loboschiza koenigiana. Both species were seen throughout the year, though more often in June and July. The known host plant for Loboschiza koenigiana, Hibiscus rosa sinensis (Shubhalaxmi 2018), is abundant in the study area, accounting for its common presence.
Moth diversity was not constant through the various months of the year. The data collected by the authors suggests that moth diversity peaked from June till October, with the month of July recording the greatest number of species of moths. The rise and fall in the diversity of months were very drastic as seen in Figure 2. The sudden peak in May to June may be due to occasional showers and possible local movement of moths due to the south-west monsoon. The second peak was seen during the month of October that dropped post November. A similar trend was observed during the survey carried out at Adyar Eco-Park, Chennai in 2019 (Nagarajan et al. 2021). A conjecture that may be derived based on the observations from the current study, is that the north-east monsoon, which is known to arrive in Tamil Nadu during that time, may facilitate moth emergence in that period. These are conjectures that need a continuous study to confirm. However, moth diversity was seen to drop post November at the study site. Further study on the effect of temperature on moth diversity must be conducted.
The most diverse family of moths recorded was the family Erebidae, with 39% of moths recorded in the study belonging to this family, followed by Crambidae (30%), Geometridae (8%) and other families. This order in species diversity among the various moth families was similar to the diversity of moths from a study recently conducted from Banaras Hindu University, Varanasi, India (Nayak & Ghosh 2020). The study highlights that the polyphagous nature of moths belonging to the superfamily Noctuoidea might account for their higher species richness in the urban localities like Banaras.
The results of the current study were compared to the findings of other moth diversity studies (Singh et al. 2021) recorded 19 species of moths from the urban landscape of Jodhpur. However, this lower species diversity can be attributed to the difference the in the natural vegetation between Jodhpur and Chennai. Since there is a deficit in published urban moth studies from India, the authors of the current study have chosen to highlight our results with any published report from an urban environment. Figure 3 shows the species distribution among the various families of moths recorded.

CONCLUSION
Moths are as abundant as butterflies in urban spaces. A total of 135 species of moths were recorded from Valmiki Nagar over a span of two years. Of these, 97 species were photographed and have been presented in the current work. The most diverse family in the study area was the family Erebidae. Nectaring plants that were often used by moths in the study area were observed and reported in the current work. The current work would hopefully serve to bring more urbanites to watch moths, thereby contributing to a greater understanding of the role of moths in urban ecosystems.