Isometrus Ehrenberg, 1828

Deshpande, Shubhankar, Gowande, Gaurang, Bastawade, Deshabhushan & Sulakhe, Shauri, 2022, A new species of Isometrus Ehrenberg, 1828 (Scorpiones: Buthidae) from southeastern plains of Tamil Nadu, India, Euscorpius 353, pp. 1-19 : 5

Isometrus Ehrenberg, 1828

( Figures 1–33 , Tables 1–5)

Isometrus (selected references): Pocock, 1893: 297; Pocock, 1900: 44 (in part); Vachon, 1972: 169; Tikader & Bastawade, 1983: 254 (in part); Kovařík, 1994: 189 (in part); Fet & Lowe, 2000: 146 (in part; complete reference list until 1998); Kovařík, 2003: 1 (in part); Kovařík & Ojanguren, 2013: 180 (in part).

TYPE SPECIES. Scorpio maculatus DeGeer, 1778

Figures

Figures 1–2: Figure 1. Тhe telson of I. wayanadensis Sulakhe et al., 2022, male, holotype BNHS SC 190 (bracket showing the character ‘telson vesicle length’). Illustration by Ruta Karmarkar. Figure 2. Isometrus longitelson sp. n., male, paratype, BNHS SC 287 in vivo habitus.

Figures 3–7. Isometrus longitelson sp. n., male, holotype, dorsal (3) and ventral (4) views, sternopectinal area (5), telson lateral (6) and ventral (7) views. Scale bars = 5 mm (3– 4); 2 mm (5, 6–7).

Figures 8–11. Isometrus longitelson sp. n., male, holotype, dorsal (8) and ventral (9) views under UV light, carapace under white light (10), carapace under UV light (11). Scale bars = 5 mm (8, 9); 2 mm (10, 11).

Figures 12–17. Isometrus longitelson sp. n., male, holotype. Pedipalp chela dorsal (12) and ventral (13) views, patella dorsal (14) and external (15) views, femur dorsal (16) and internal (17) views. Trichobothrial pattern indicated by yellow circles. Scale bar = 1 mm.

Figures 18–22. Isometrus longitelson sp. n., female, paratype, BNHS SC 290, dorsal (18) and ventral (19) views carapace in dorsal view (20), sternopectinal area (21), and telson in lateral view (22). Scale bars = 5 mm (18–19); 2 mm (20–22).

Figures 23–26. Isometrus longitelson sp. n., male, holotype, metasoma in dorsal (23), ventral (24) and lateral (25) views under UV light and mesosomal tergites V–VI of dorsal view under UV light (26). Scale bars = 5 mm (23–25); 2 mm (26).

Figures 27–29. The type locality of Isometrus longitelson sp. n., Tamarindus sp. on which specimens were observed (27), а hillock near the type locality (28), Chengalpattu-Thiruporur Road, Keelavedu village from where the type series was collected (29).

Figures 30–31: Figure 30. Boxplots showing variations in ratios of telson length to depth in males for all Isometrus species from India except I. maculatus DeGeer, 1778. Figure 31. Maximum Likehood phylogenetic tree (ML) for Isometrus. Values along the nodes are ultrafast bootstraps for 1000 iterations.

Figure 32. Bayesian phylogenetic tree for Isometrus. Values along the nodes are Bayesian posterior probabilities for Bayesian Inference.

Figure 33. Distribution of Indian Isometrus species with elevation data. The stars represent the type localities.