Isotomurus jharkhandensis, Mandal & Suman & Bhattacharya, 2017

Mandal, G. P., Suman, K. K. & Bhattacharya, K. K., 2017, Five new species of Collembola (Isotomidae) from Jharkhand, India, Records of the Zoological Survey of India 117 (2), pp. 97-112 : 103-104

4. Isotomurus jharkhandensis n. sp.

(Plate 4, Figures 1-20, Table 4)

Material examined: HOLOTYPE: female on slide, India: Jharkhand: 7km from Rajrappa, Kuju range, Ramgarh forest , Ramgarh district , 26. xii. 2014, Lat and Long. N 22˚38’58.0”and E 86˚30’5.2”, collected by G. P. Mandal, Registration No. 1984/H14/ZSI. PARATYPE: 01 ex on slide, India: Jharkhand: 7km from Rajrappa, Kuju range, Ramgarh forest, Ramgarh district, 26. xii. 2014, Lat and Long. N 22˚38’58.0”and E 86˚30’5.2”, collected by G. P. Mandal, Registration No. 1985 /H14/ZSI ; PARATYPE: 11 exs in ethyl alcohol, India: Jharkhand: 7km from Rajrappa, Kuju range, Ramgarh forest , Ramgarh district ,

26. xii.2014, Lat and Long.N 22˚38’58.0” and E 86˚30’5.2”, collected by G. P. Mandal, Registration No. 1986 /H14/ ZSI; 01 ex on slide, India: Jharkhand: 7km from Rajrappa, Kuju range, Ramgarh forest, Ramgarh district, 26. xii. 2014, Lat and Long. N 22˚38’58.0”and E 86˚30’5.2”, collected by G. P. Mandal, Registration No. 1987 /H14/ ZSI; 01 ex on slide, India: Jharkhand: Damodar River bed near Ramgarh, Ramgarh district , 23. xii. 2014, collected by G. P. Mandal, Registration No. 1988/H14/ZSI; 01 ex on slide, India: Jharkhand: Birsa Mrig Bihar, Ranchi district ,

20. xii. 2014, collected by G. P. Mandal, Registration No. 1989/H14/ZSI; 01 ex on slide, India: Jharkhand: Asanpani, Ghatsila, East Singbhum district , 28. vi. 2014, Lat and Long N 22˚45’18.8”and E 86˚26’56.8” collected by G. P. Mandal, Registration No. 1990/H14/ZSI; 01 ex on slide, India: Jharkhand: Amaghata Forest, Dhanbad district , 07. ix. 2013, Lat & Long. N 23°49’43.4” and E 86°30’13.3”, collected by G. P. Mandal, Registration No. 1991/H14/ZSI.

Description: Body length up to 1.93 mm (excluding appendages).

Colour Pattern: Background colour yellowish white. Eyes dark blue-black, one anterior & one median black spot present between eyes. Base of antenne and posterior side of head pigmented with violettish blue. Ant - I, II laterally pigment, Ant – III and IV darker. Pre coxae and coxae lightly pigmented, tibiotarsi laterally pigmented, ventral tube without pigment. Th. II to Abd. I. pigmented near the border. Abd. II to Abd. IV pigmented with violettish blue transversely, form a distinct flecks like structure. Abd.V –VI pigment laterally. Body with dark dorso median line on Th. II – Abd. III, much broader near the border of segments. Abd. II – Abd. IV with 3+3, 3+3, 1+1 hollow spots marking the base of bothritrichia. Furcula unpigmented (Figures 1 and 2).

Head: Eyes 8+8, more or less equal (Figure 3). P.A.O elongate, slender type, unconstricted, no setae near the base. P.A.O is 1.15 times as long as the diameter of largest eye. Antennal segment ratio in length as I: II: III: IV = 1:

1.7: 1.8: 2. Third antennal segment with blunt seta and curved setae along with smooth setae (Figure 4). Fourth antennal segment without apical bulb, but pin setae, many curved setae present (Figure 5). Labrum with 4 longitudinal ridges, maxillary outer lobe with 4 sub-lobal hairs (Figure 6).

Thorax and Legs: Ratio of segments of Thorax II: III = 1:

0.9. Body setae smooth and ciliate. Large multilaterally ciliate macrochaetae present in the abdomen. One large macrochaetae present on each tibia tarsus of all legs (Figure 7). Unguis strong, with one outer teeth, no inner and lateral tooth. Unguiculus short, broad, without teeth (Figure 8). Tenent hair thin, acuminate, 1.5 times less than unguis (Figure 9). Ventral tube with 12 – 15 laterodistal, 18 anterior and 24 posterior setae (Figures 10, 11 & 12). Trochanteral organ with 16-17 setae (Figure 13).

Abdomen: Ratio of segments of Abdomen I: II: III: IV: V: VI: 1: 1.6: 2: 1.3: 0.9: 0.8. Retinaculaum with 4 teeth and 8-10 setae in each (Figure 14). Manubrium: dens: mucro 1: 2: 0.06. Manubrium with large no of lateral setae (Figure 15). Den with numerous posterior setae (Figure 16). Dens longer than manubrium and crenulate. Mucro quadridentate, without seta(Figure 17). Lamella on proximal tooth present.

Body Chaetotaxy: Body clothed with normal setae on head, thorax and abdomen (Figure 18). Multilaterally long ciliate macrochaetae present on abdomen (Figure 19). Cephalic portion without macrochaetae (Figure 20). Ant III and IV with curved setae and blunt setae present. Ant. IV with pin seta.

Ecology: Found under thick bed of mosses of semi dried Damodar river bed of Ramgarh district, Jharkhand, India

Etymology: The new species is named after the type locality, Jharkhand, India.

Remarks: This species belongs to Palustris group having trichobothria 3, 3, 1. Abd. V with 7+7 sensillum, retinaculum with more than 6 setae. Inner tooth on the claw, seta and lamella on the mucro variable. Colour variation found & few specimens are also found in lighter forms.

Discussion: The new species from Ramgarh, Ranchi and East Singbhum districts of Jharkhand, India can easily distinguished from other known species of Isotomurus by colour pattern, claw structure, setae on ventral tube and retinaculum, and macrochaetae on tibia-tarsus. It is close to Isotomurus punctiferus Yosii, 1963 , in having similar type with dark dorsomedian line on Th II – Abd III, P.A.O and claw with one outer tooth but strongly differ from Isotomurus punctiferous in the characteristics given below in the Table 4.

Characters Isotomurus punctiferus Yosii, 1963 Isotomurus jharkhandensis n. sp.

Colour pattern Greyish white. One black fronto-median Yellowish white. Two black spots, one in between spot. Antennae, ventral tube and tibio tarsus base of two antennae and other one fronto-median darker, all segments with narrow bands on side. Abd. II – Abd. IV pigmented and forming a the anterior edge, lateral parts also darker. flake like structure. Th. II – Abd. I pigmented near the border, Abd. V – VI pigmented laterally. Ventral tube unpigmented.

Unguis and Unguiculus Unguis with two lateral teeth & one outer Unguis without lateral tooth & one outer tooth & tooth & without inner tooth. Unguiculus without inner tooth. Unguiculus without tooth.

with inner tooth.

Ventral tube Ventral tube with 9 – 18 + 9 – 18 laterodistal, Ventral tube with 12 – 15 latero distal, about 18 about 20+20 anterior and 30 posterior setae anterior and 24 posterior setae.

Tibiotarsus with macrochaete Tibiotarsus without macrochaetae. Tibiotarsus with one ciliate macrochaetae.

Trochanteral organ Trochanteral organ unknown. Trochanteral organ with 16-17 setae.

Retinaculum with setae Retinaculum with 10 – 20 setae. Retinaculum with 8-10 setae.

Mucro Mucro with seta. Mucro without seta.

Body length 2.6 mm 1.93 mm