A new species, Oedothorax khasi sp. nov., is described from the Indian state of Meghalaya on the basis of a single male. The species is similar to the Oriental O. myanmarTanasevitch, 2017, different in some details of palpal structure.
INTRODUCTION
At present, the spider fauna of India comprises of 14 species of Oedothorax Bertkau in Förster & Bertkau, 1883, which are distributed in equal proportions between the Oriental and the Palaearctic parts of the country (see Tanasevitch, 2015, 2016, 2017). An eighth Oedothorax from Oriental India is described below. The single male available of this new species was collected from montane subtropical forests in the Khasi Hills, a territory belonging to the Garo-Khasi range in the Indian state of Meghalaya.
MATERIAL AND METHODS
This paper is based on material kept at the Muséum d'histoire naturelle de Genève, Switzerland (MNHG). Specimens preserved in 70% ethanol were studied using a MBS-9 stereomicroscope. The sample number is given in square brackets.
Terminology of copulatory organs mainly follows that of Merrett (1963), Hormiga (2000) and Tanasevitch (2015). Chaetotaxy is given in a formula, e.g., 2.2.1.1, which refers to the number of dorsal spines on tibiae I-IV. The sequence of leg segment measurements is as follows: femur + patella + tibia + metatarsus + tarsus. All measurements are given in mm. Scale lines in the figures correspond to 0.1 mm unless indicated otherwise. Figure numbers are given above the scale lines, the alternative distance below.
TAXONOMY
Oedothorax khasi
sp. nov.
Figs 1–7
Holotype: Male; INDIA, Meghalaya, Khasi Hills, 16 km SW of Mawsynram, between Mawsynram and Balat, 1000 m a.s.l.; sifting in forest, in ravine; 27.X.1978; leg. C. Besuchet & I. Löbl [30b].
Diagnosis: The new species is characterized by an essentially unmodified carapace, by the shape of the dorsal apophysis of the palpal tibia, as well as by a relatively large, cylindrical radix and by a very short embolus.
Etymology: The specific name is a noun in apposition referring to the mountain range in which lies the type locality.
Description: Male (holotype). Total length 1.80. Carapace 0.85 long, 0.60 wide, pale greyish brown. Cephalic part of carapace somewhat elevated and protruded forward as shown in Fig. 1. Eyes slightly enlarged. Chelicerae 0.33 long, unmodified. Legs pale brown. Leg I 3.46 long (0.93+0.25+0.85+0.78+0.65), IV 3.22 long (0.88+0.23+0.83+0.80+0.48). Chaetotaxy 2.2.1.1, length of spines about 1.5 times diameter of segment. All metatarsi with a trichobothrium. TmI 0.63. Palp (Figs 2–7): Tibia carrying a wide dorsal apophysis with a small invagination apically and two small tubercles retrolaterally. Paracymbium somewhat L-shaped. Distal surface of tegulum membranous. Distal suprategular apophysis short, wide, rounded distally. Embolus very short, radix relatively large, cylindrical, with a fold on its exterior surface. Convector with a wide lateral extention and a short, pointed distal apophysis. Main body of convector long, tapering posteriorly. Abdomen 1.15 long, 0.63 wide, dorsally pale, with an indistinct grey herring-bone pattern. Female. Unknown.
Taxonomic remarks: Oedothorax khasi sp. nov. is similar to another Oriental species, O. myanmar, recently described from mountains of the Chin State in Myanmar (Tanasevitch, 2017). The new species is clearly distinguished by the shape of the dorsal apophysis on the palpal tibia, as well as by the relatively large and not curved radix.
Distribution: Only known from the type locality in northern India.
Figs 1–7.
Oedothorax khasi sp. nov., holotype. (1) Carapace, lateral view. (2) Distal part of right palp, retrolateral view. (3–4) Palpal tibia, dorsal and retrodorsal view, respectively. (5) Paracymbium. (6) Distal suprategular apophysis and embolic division, retrolateral view. (7) Embolic division, prolateral view.
ACKNOWLEDGEMENTS
I am grateful to Peter Schwendinger (MHNG) for the opportunity to work with the collections of the MHNG and for his valuable comments on the manuscript. Thanks also go to Shou-Wang Lin (University of Greifswald, Germany) for reviewing the manuscript.
