Figures 585–587: Figure 585. Locality 15CI, Sri Lanka, Northern Province, Mannar District, Marichchukkaddi env, border of Wilpattu National Park, 08°33'32.3"N 079°56'51"E, 7 m a.s.l. During night collecting on 25.–26.IV.2015 (UV detection) we recorded Isometrus maculatus and Isometrus thwaitesii sympatrically (running on branches and trunks of trees, also sitting on leaves one to four metres high), Reddyanus ceylonensis sp. n. (on the land among leaves; the type locality), Reddyanus loebli (hidden under scales of bark of standing tree trunks). Near to the locality we recorded temperature between 37.6 ºC (maximum daytime temperature and 26.2 ºC (minimum nighttime temperature) shortly before sunrise. Humidity varied between 67% and 81%. Figures 586–587. Locality 15CJ, Sri Lanka, Northern Province, Jaffna District, 09°42'51.6"N 080°04'44.8"E, 19 m a.s.l. During night collecting on 26.–27.IV.2015 (UV detection) we recorded Lychas srilankensis (on the land usually under branches, leaves or in their vicinity), Heterometrus swammerdami (inside the termite constructions or inside heaps of garden "waste") and Heterometrus gravimanus inside burrows in open terrain (Fig. 587). The females had 30 to 60 cm long oblique burrows once or twice curved. A female shortly after maturity ecdysis was in the burrow together with a male; another female was in the burrow together with three juveniles which had their own narrow burrows separated under surface from the motherś burrow; a juvenile after the third ecdysis had a proper burrow 30 cm long oblique and once curved. There also lives Isometrus maculatus. On the locality we recorded night temperature 31.6 ºC– 27.2 ºC (minimum temperature) and night humidity varied between 60% and 87%.