Isotomurus indicus, 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 : 102-103

3. Isotomurus indicus n. sp.

(Plate 3, Figures 1-20, Table 3)

Material examined: HOLOTYPE: on slide, India: Jharkhand: 7 km from Rajrappa, Kuju range, Ramgarh forest , Ramgarh district , 26. xii. 2014, Lat & Long. N 22˚38’58.0”and E 86˚30’5.2”, collected by G. P.Mandal, Registration No. 1995/ H14/ZSI. PARATYPE: 01 ex on slide, India: Jharkhand: 7km from Rajrappa, Kuju range, Ramgarh forest, Ramgarh district, 26. xii. 2014, Lat & Long. N 22˚38’58.0”and E 86˚30’5.2”, collected by G. P. Mandal, Registration No. 1996/H14/ZSI ; Other materials: 07 exs in ethyl alcohol, India: Jharkhand: Amlachatar, Jamtara district , 05. ix. 2013, collected by G. P. Mandal, Registration No. 1997 /H14/ ZSI; 01 exs on slide, India: Jharkhand: Amlachatar , Jamtara district , 05. ix. 2013, collected by G. P. Mandal, Registration No. 1998 /H14/ZSI; 01 exs on slide, India: Jharkhand: Amlachatar , Jamtara district , 05. ix. 2013, Lat. and Long. N 23°58’6.1” and E 86°50’31” collected by G. P. Mandal, Registration No. 1999 /H14/ZSI ;

Description: Body length up to 1.82 mm (excluding appendages).

Colour Pattern: Background colour white. Body without distinct pigment or patches. Body without dorso-median line or flakes. Eyes dark blue-black, one anterior & one median black spot present between eyes. Ant - I, II, III & IV pigmented with blue basally.Abd. II- Abd. IV with 3+3, 3+3, 1+1 hollow dot marking the base of bothritrichia. Furcula and legs unpigmented Abd. IV with bluish spot in proximal & median. Greenish dot present Th,II- Abd. VI ventrally (Figure 1).

Head: Eyes 8+8, more or less equal (Figure 2). P.A.O slender type, unconstricted, 3 long setae near the base. P.A.O is more or less equal of the largest omma (Figure 3). Head: Antennae ratio as 2.13.Antennal segment ratio in length as I: II: III: IV = 1: 1.8: 2.17: 2.3. Ant.I with basal sensilla shown in (Figure 4). Third antennal segment with blunt seta and sensilla shown in (Figure 5). Fourth antennal segment without apical bulb, but big pin setae (Figure 6). Maxillary outer lobe with 4 sublobal hairs (Figure 7) .

Thorax and Legs: Ratio of segments of Thorax II: III = 1: 1.08. Thoracic setae smooth and ciliate. Three large macrochaetae present on each tibia tarsus of all legs (Figure 8). Unguis strong, long with one outer large tooth in the proximal, and one lateral tooth but no inner tooth. Unguiculus short, broad, without teeth (Figure 9). Unguis

2.6 times longer than unguiculus. Tenent hair thin, acuminate, 1.5 times less than unguis (Figure 10). Ventral tube with 4+4 anterior setae (Figure 11). Trochanteral organ with 20 setae (Figure 12).

Abdomen: Ratio of segments of Abdomen I: II: III: IV: V: VI: 1: 1.2: 1.6: 1.4: 0.7: 0.6. Retinaculaum with 4 teeth and 6 setae in each (Figure 13). Manubrium: dens: mucro 1: 1.6: 0.08. Manubrium with large no of lateral setae (Figure 14). Den with numerous lateral setae (Figure 15). Dens longer than manubrium and crenulate. Mucro quadridentate, lamella present on base of mucro but without seta (Figure 16).

Body Chaetotaxy: Body clothed with normal ciliate smooth setae on head, thorax and abdomen. Abd.VI with long ciliate setae present (Figures 17, 18 & 19). Abd. V with 7+7 sensilla shown in (Figure 20).

Ecology: Found under moist nullah cover by leaf litter of Kuju range, Ramgarh forest, Ramgarh district and moist nullah of Amlachatar of Jamtara district, Jharkhand, India.

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

Characters Isotomurus jharkhandensis n. sp. Isotomurus indicus n. sp.

Colour pattern Body with distinct pigment patches and Th.II- Abd. Body white, no distinct pigment patches except

I pigmented near the border, dark dorso-median line antennae and eyes. 3,3,1 holloow dot/spot present present from Th.II- Abd. IV. Abd. II-IV forming a on Abd.II-IV.

flake like structure, Abd.V – VI pigmented laterally.

P.A.O P.A.O. is 1.5 times as long as the largest omma and no P.A.O. is more or less equal to the largest omma setae near the base. and 3 long setae near the base.

Unguis & Unguiculus Unguis with one outer tooth but no lateral & inner Unguis with one outer & one lateral tooth and tooth. Unguiculus without tooth. without inner tooth. Unguiculus without tooth.

Ventral tube Ventral tube with 18+18 anterior setae. Ventral tube with 4+4 anterior setae.

Tibiotarsus with Tibiotarsus with one ciliate macrochaetae. Tibiotarsus with three ciliate macrochaetae.

macrochaete

Trochanteral organ Trochanteral organ with 16-17 setae. Trochanteral organ with 20 setae.

Retinaculum with setae Retinaculum with 8-10 setae. Retinaculum with 6 setae.

Body length 1.93 mm 1.82 mm

Remarks: This species also belongs to Palustris group having trichobothria 3, 3, 1. Abd. V with 7+7 sensillum, retinaculum with 6+ 6 setae.

Discussion: The new species from Ramgarh and Jamtara districts of Jharkhand, India can easily distinguished from other known species of Isotomurus by pigment pattern, claw structure, setae on ventral tube and retinaculum, and macrochaetae on tibia-tarsus. It is close to Isotomurus jharkhandensis n. sp., in having similar type of outer teeth on unguis but strongly differ in colour pattern and other characteristics given below in the Table 3.