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bioRxiv · 10.1101/2021.05.17.444399

Three new species of nematodes from the syconia of Ficus racemosa in southern India

Abstract

SummaryFicus racemosa with an Indo-Australasian distribution, has so far been recorded to harbour in its fruits, nematode species of the aphelenchoid genera Schistonchus, Ficophagus and Martininema, and species of diplogastrid genera Teratodiplogaster and Pristionchus. The Indian species reported so far from Ficus racemosa lack comprehensive details on morphology and molecular characterization. In this paper, we describe three new species of nematodes obtained from syconia (enclosed globular infructescence or fruit) of Ficus racemosa found in southern India. Ficophagus glomerata n. sp. is characterised by small body having b=5.2-9.6, c= 18-23; slightly set-off lip region having well developed cephalic framework; secretory-excretory pore opens near the head; slender stylet with small, rounded/ sloping knobs; ovoid median bulb with relatively posteriorly-placed valve plates; males with sickle-shaped spicules having spatulate or hammer-shaped capitulum, represented by an elongate-ovoid condylus and long digitate rostrum and tail conoid with fine, hair-like terminal spike. Teratodiplogaster glomerata n. sp. is characterised by long tubular and narrow stoma with fractal pieces in prostegostom; long rectangular metacorpus; female reproductive system with conspicuous spermatheca and amoeboid sperms; males having short, arcuate spicules and keeled gubernaculum; genital papillae in the configuration of P1, P2, C, P3, P4, P5d, (P6d, P7), P8d, Ph and tail conoid with a terminal or subterminal mucro. Pristionchus glomerata n. sp. is characterised by four morphotypes mainly with variations in lip region, stoma, spicules, gubernaculum, and the position of genital papillae. Phylogenetic analyses based upon near-full-length small subunit (SSU) and D2-D3 expansion segments of large subunit (LSU) rRNA genes confirmed affinities with sister species of corresponding genera.

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Gupta, S., Tahseen, Q., Borges, R. M.. 2021-05-17. Three new species of nematodes from the syconia of Ficus racemosa in southern India. https://doi.org/10.1101/2021.05.17.444399

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