Altitudinal gradient affect abundance, diversity and metabolic footprint of soil nematodes in Banihal-Pass of Pir-Panjal mountain range.

Despite enormous diversity, abundance and their role in ecosystem processes, little is known about how community structures of soil-inhabiting nematodes differ across elevation gradient. For this, soil nematode communities were investigated along an elevation gradient of 1000-2500 masl across a temperate vegetation in Banihal-Pass of Pir-Panjal mountain range. We aimed to determine how the elevation gradient affect the nematode community structure, diversity and contribution to belowground carbon assimilation in the form of metabolic footprint. Our results showed that total nematode abundance and the abundance of different trophic groups (fungivores, herbivores and omnivores) declined with the increase of elevation. Shannon index, generic richness and evenness index indicated that nematode communities were more diverse at lower elevations and declined significantly with increase in elevation. Nematode community showed a pattern of decline in overall metabolic footprint with the increase of elevation. Nematode abundance and diversity proved to be more sensitive to elevation induced changes as more abundant and diverse nematode assemblage are supported at lower elevations. Overall it appears nematode abundance, diversity and contribution to belowground carbon cycling is stronger at lower elevations and gradually keep declining towards higher elevations under temperate vegetation cover in Banihal-pass of Pir-Panjal mountain range.

A new species of the rare nematode genus Rostrulium Siddiqi, 1995 (Nematoda: Dorylaimida: Tylencholaimidae) from India.

Rostrulium indicum sp. n. is described and illustrated from Western Ghats, India. The new species is characterized by having a 2.1 mm long body; lip region offset by slight constriction; odontostyle 17.5 µm and odontophore 18 µm long, guiding ring single; pharynx with slender anterior part which expands gradually into the cylindrical basal bulb occupying about 30% of total neck length; female genital system didelphic-amphidelphic, transverse vulva, short rounded conoid tail and male with 40 µm long spicules, lateral guiding pieces and three spaced ventromedian supplements. This is the first report of this rare genus since its original description from Cameroon.

Epidorylaimus monhystera sp. n., an atypical species of the genus Epidorylaimus Andrássy, 1986 (Dorylaimida: Qudsianematidae) from Japan.

Epidorylaimus monhystera sp. n. is described and illustrated from Japan. The new species is characterized by having 1.12-1.33 mm long body, lip region offset by slight constriction, odontostyle 15-16 µm and odontophore 18-20 µm long, guiding ring single, pharyngeal expansion gradual, vulva transvers, female genital system mono-opisthodelphic, anterior branch completely absent and tail elongated-conoid, ventrally arcuate. It is distinctive from all other species of the genus Epidorylaimus in having mono-opisthodelphic female genital system. Its relationship with other monodelphic genera of Qudsianematidae is also discussed and an emended diagnosis of the genus Epidorylaimus is provided with list of valid species, key for their identification and a diagnostic compendium.