Taxonomic notes on the genus Epeus Peckham & Peckham, 1886 (Araneae, Salticidae) from India

This paper provides the re-description of Epeus albus Prószynski, 1992, with the first description of its male. Additionally, Epeus chilapataensis (Biswas & Biswas, 1992) is synonymised with E. albus and a new taxonomic combination is proposed: Epeus khan-dalaensis (Tikader, 1977) comb. nov. (ex Phidippus ). Clarification on the record of Epeus daiqini Patoleta, Gardzińska & Żabka, 2020 from India is provided. The current distribution of the genus in India is also mapped.


Introduction
Members of the jumping spider genus Epeus Peckham & Peckham, 1886, are medium-to-large-sized spiders recorded from subtropical Himalayan valleys, through India, Indochina, southern China, Philippines and Sunda Archipelago (Patoleta et al. 2020;World Spider Catalog 2024).The living specimens of Epeus are usually light green or yellow in colour with palpi and legs of various colours (Sebastian and Peter 2009;Prószyński and Deeleman-Reinhold 2012;Mondal et al. 2020).Till now, the genus comprised 22 valid species, of which five have been reported from India: Epeus albus Prószynski, 1992; Epeus chilapataensis (Biswas & Biswas, 1992); Epeus daiqini Patoleta, Gardzińska & Żabka, 2020;Epeus indicus Prószyński, 1992;and Epeus triangulopalpis Malamel, Nafin, Sudhikumar & Sebastian, 2019 (Caleb and Sankaran 2024;World Spider Catalog 2024).The original description of E. albus Prószynski, 1992 was based on the female specimen collected from Orissa (now Odisha).During field surveys conducted in the Southern Western Ghats of India, we collected both male and female specimens of Epeus albus and this has led to the realisation that several taxa of this genus in India require re-evaluation.The paper thus aims to provide: (1) first description of the hitherto unknown male of E. albus and re-description of the female, based on the fresh materials; (2) update the current taxonomic status of E. chilapataensis and Phidippus khandalaensis Tikader, 1977; (3) clarify the record of E. daiqini Patoleta, Gardzińska & Żabka, 2020 from India; and (4) provide a distribution map of all known Indian Epeus spp.

Material and methods
The specimens were preserved in 70% ethanol and are deposited in the National Zoological Collections of the Zoological Survey of India (NZC-ZSI), Kolkata, India.The terminology used in the text and figures follows Patoleta et al. (2020) and leg spination follows the system used by Bosselaers and Jocqué (2000).Specimens were examined under a Leica M205A stereomicroscope and images were taken using a Flexacam C3 camera attached to the stereomicroscope and processed using extended focus montage LAS X software.All measurements are given in millimetres (mm).Pedipalp and leg measurements are given as follows: total length [femur, patella, tibia, metatarsus (except for palp), tarsus].The distribution map was prepared using the online mapping software SimpleMappr (Shorthouse 2010).

Taxonomy
Family Salticidae Blackwall, 1841 Genus Epeus Peckham & Peckham, 1886 Type species.Epeus tener (Simon, 1877) Diagnosis.Species of this genus can be distinguished from other members of the tribe Plexippini by the high and elevated carapace, male palp with flattened and elongated cymbium, postero-ventrally pointing retrolateral basal apophysis, tegulum with a tongue-like basal process, filiform embolus surrounding the semicircle of tegulum and extending to the distal end of cymbium and the epigyne with a shallow anterior depression and long copulatory ducts forming several loops (Meng et al. 2015;Malamel et al. 2019).
Diagnosis.The male copulatory organ of Epeus albus Prószyński, 1992 is most similar to that of Epeus glorius Żabka, 1985 in having the similar shaped RTA and serrated cymbial apophysis, but it can be distinguished by the following combination of characters: RTA slender and anterodorsally directed (RTA relatively robust and apically directed in E. glorius); cymbial apophysis relatively short and posteroventrally directed (long and posteriorly directed in E. glorius) (cf.Figs 2A, B, 3A, B with figs 15-16 in Meng et al. (2015)).The female of E. albus is most similar to that of Epeus indicus Prószyński, 1992 and Epeus szirakii Patoleta, Gardzińska & Żabka, 2020 in having the similar epigynal morphology, but it can be distinguished by the following combination of characters: epigyne with large and wide atrium (narrower in E. indicus); copulatory openings more widely separated from each other, orientated more anteriorly with well-defined posterior margins (closely arranged, orientated face to face without well-defined posterior margins in E. indicus).Justification of the synonymy of E. chilapataensis.Re-examination of the holotype of E. chilapataensis shows that the body colour pattern and epigyne structure are similar to those of Epeus albus: pale yellow to white-coloured body without any prominent markings and crescent shaped copulatory openings and the similar course of proximal spermathecal loop (cf.Figs 3E, 5A-C, E with figs 20-21, 25 in Prószyński (1992)).Based on these observations, we consider E. chilapataensis a junior synonym of E. albus.Prószyński (1992) described E. albus from Jajpur-Keonjahr District, Orissa and Biswas and Biswas (1992) described E. chilapataensis from Koch Bihar District (now Cooch Behar), West Bengal.Both the species were described from the eastern part of the country from neighbouring states in the same year, but in different months.Prószyński described E. albus in October 1992 and Biswas & Biswas described E. chilapataensis in November 1992.Here, we are giving preference to the name which was first described.Therefore, the second described species must be a junior synonym of the first.
Remarks.Mating plugs were found covering the copulatory openings of the holotype female of E. chilapataensis (Biswas & Biswas, 1992) and of several other females examined from Karnataka and Meghalaya (Figs 3E, F, 4A-F, 5C, D).
The record of Epeus daiqini Patoleta, Gardzińska & Żabka, 2020 from India was based on the male and female specimens collected from Pathanamthitta, Kerala (Sibi et al. 2023).However, illustrations of the male and female copulatory organs provided by Sibi et al. (2023) do not match those of the type specimens of E. daiqini: the male palp with serrated cymbial apophysis (absent in the holotype male of E. daiqini); relatively short and less coiled copulatory ducts (long and strongly coiled in the paratype female of  Epeus khandalaensis (Tikader, 1977), comb.nov.Justification of the transfer.Tikader (1977) described this species, based on a female specimen collected from Poona, Maharashtra.The ZSI collection has a single glass bottle for this species, containing a female specimen (labelled as 'holotype') in good conditions with detached abdomen and broken legs.The genitalia of the female was dissected, but was not found inside the bottle and is perhaps lost.The general morphology shows that this species shares the features of Epeus Peckham & Peckham, 1886: carapace high and elevated, AME much larger than ALE and the latter slightly behind AME (Patoleta et al. 2020) and the abdomen dorsally with indistinct black markings and white spots (Fig. 6A-C).Based on these observations, we are provisionally transferring it to Epeus.
E. daiqini) (cf.figs 3E-G and 4G-H in Patoleta et al. (2020) with figs 1D-F and 2D-E in Sibi et al. (2023)).Their genital morphology is similar to those of freshly-collected male and female specimens of E. albus (cf.Figs 2A-E, 3A-D, 4A-F with figs 1D-F and 2D, E in Sibi et al.(2023)).Based on these observations, it is apparent that the species is misidentified bySibi et al. (2023) and it belongs to E. albus.

Figure 7 .
Figure 7. Map showing the distributional records of Epeus species in India.
Type material.