Report of Platythomisus octomaculatus (C. L. Koch, 1845) and Platythomisus sudeepi Biswas, 1977 from India (Araneae, Thomisidae)

Abstract Background The genus Platythomisus Doleschall, 1859 presently comprises 13 valid species, nine known from Africa and four from Asia. All Platythomisus species are known from females only, except P. jucundus Thorell, 1894 and P. sudeepi Biswas, 1977 from both sexes and P. quadrimaculatus from juvenile. Only, P. sudeepi was reported from India. New information Platythomisus octomaculatus (C. L. Koch, 1845) is recorded after 120 years of its last report; newly recorded from Assam, India which extends its distribution from the previously known localities, Java and Sumatra. Platythomisus sudeepi is newly recorded from the Maharashtra State. The variation in the number of abdominal spots on juvenile, sub-adult and adult of P. octomaculatus observed during rearing is reported. Although, the species name 'octomaculatus' suggests eight spots, we observed that the anterior pair of abdominal spots is fused in adults.


Introduction
During a field survey in the private property of Makunda Christian Leprosy & General Hospital, Karimganj District, Assam, we found a bright yellow thomisid spider with black spots. Based on the literature Koch (1845), Doleschall (1859), Hasselt (1882) and Simon (1895) we were able to identify it as Platythomisus octomaculatus (C. L. Koch, 1845). Another pale red coloured female Platythomisus with three transverse black bands was collected from Dapoli in the Western Ghats of Maharashtra. Biswas (1977) and Siliwal and Molur (2005) revealed its identity to be Platythomisus sudeepi Biswas, 1977. Koch (1845) described Thomisus 8-maculatus based on female from 'Ostindien' which is a German term for East Indies (in present day Indonesia), where he stated that the spider has 8 black spots on its dorsum and has also been represented in the diagram. Doleschall (1859) described the genus Platythomisus with the description of Platythomisus phryniformis from Java. Hasselt (1882) mentioned Thomisus 8-maculatus as Platythomisus (Thomisus) octomaculatus for his specimens from Padang, Indonesia. Later, Platythomisus phryniformis was synonymized with P. octomaculatus by Hasselt (1890). Platythomisus octomaculatus is presently known to be distributed in Sumatra and Java (Koch 1845, Doleschall 1859, Hasselt 1882, WorldSpiderCatalog 2016. Given the striking colours of this species, hundreds of photographic records are available on internet, mainly from Singapore, adding to the known distribution. Biswas (1977) described Platythomisus sudeepi based on female from Pollibetta, Coorg, Karnataka. Later, P. sudeepi was reported from Castle rock, Karnataka (Bastawade et al. 2004), Thrissur, Kerala (Siliwal andMolur 2005). Very recently, Benjamin et al. (2016) reported this species from Sri Lanka with first description of its male. Presently, P. sudeepi is known from the Western Ghats of India and Sri Lanka.

Materials and methods
Specimens are preserved in 70% alcohol, deposited at the Bombay Natural History Society (BNHS), Mumbai. Specimens were studied under a Leica stereozoom (MZ6) microscope, photographed using mounted Canon Powershot S50 camera, assembled using Combine ZM software and the images were processed with Adobe Photoshop CS5. Measurements were done with Erma stage and ocular micrometer and an accurate scale. Epigyna were cleared in 10% KOH and kept in Polyvinyl Lactophenol (PVLP) gel with Lignin pink stain for seven days before imaging. All measurements are in millimetres; measurements of other specimen of P. octomaculatus are provided in parentheses. Map was produced with DIVA-GIS v. 7.5c, with geographical coordinates obtained from Google Earth.
Remarks: Koch (1845) most likely named the species as 'octomaculatus' for the eight apparent abdominal spots as shown in his illustration. Doleschall (1859) described his specimen of P. octomaculatus had seven round black spots on the dorsum of which the first one is unpaired. Hasselt (1882) mentioned that his specimens match with that of Doleschall's with the seven spots on abdomen; as also seen in our specimens. Eight spots are present in the sub-adult female of P. octomaculatus, of which the first pair of spots is merged in the adults as observed in Singaporean specimens (pers comm. David Court, Singapore). It was also observed that the size of these seven spots was variable before and after egg laying (Fig. 2). The young ones emerging from the egg case of P. octomaculatus (Fig. 3a) have only two abdominal spots at early stages (Fig.  3b). In the specimens from Java and Fort de Kock, Sumatra (deposited at the NHMW), Singapore and India, the position of spots on carapace and abdomen seems to be constant, however their size is variable.

Distribution
Known from localities in Java, Sumatra and India (see map, see Introduction). a b Figure 2.
The epigynum illustrated in Benjamin et al. (2016) shows kidney-shaped spermathecae versus oblong shape in our specimen, although it position and shape is similar. Our low sample size did not allow studying the range of variation in this species and needs further examination.

Distribution
Known from several localities in the Western Ghats of India and Sri Lanka (Fig. 5, see Introduction).