Eutyphoeus yangoupokpensis Tiwari & Yadav, 2025

Eutyphoeus yangoupokpensis Tiwari & Yadav sp. nov.

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Figs 9 View Fig , 14 View Fig ; Tables 1–2 View Table 1 View Table 2

Diagnosis

Length 60–80 mm, diameter 3.7–4 mm, segments 84–140. Prostomium tanylobic. First dorsal pore in 10/11. Male genital orifices bivestibulate, pentagonal vestibula, apenile, between ab just beneath the pear-shaped papillae. One pair of spermathecal pores in intersegment 7/8 at b encircled with 4–5 small circular genital markings. Genital markings paired on xvi post setal, at b, single median on xvii. Sometimes paired on xviii post setal, at b and absent on xvii. Septa 6/7/8/9 absent. Intestinal caeca in xxvi, small, ventrally directed. Holandric, seminal vesicles in ix and xii, anterior one with distinct hexagonal chambers, posterior one extends up to xvi. Three pairs of supra-intestinal glands. Prostate tubular, duct elongated, wide at posterior end. Bidiverticulate spermathecae. Penial setae ornamented with triangular teeth in transverse rows, tip blunt, slightly bent on anterior region. Genital marking glands present.

Etymology

The species epithet ‘ yangoupokpensis ’ is after the Yangoupokpi-Lokchao Wildlife Sanctuary in Tengnoupal, Manipur, where it was discovered.

Material examined

Holotype

INDIA – Manipur • clitellate (2–3 segments from caudal region taken for DNA extraction); Tengnoupal, Yangoupokpi-Lokchao Wildlife Sanctuary ; 24.3831° N, 94.1492° E; 10 Oct. 2017; Shweta Yadav leg.; registration number – ZSI CZRC T/8; MNP17-1086-44A12 . GoogleMaps

Paratypes

INDIA – Manipur • 2 clitellates; same data as for holotype; MNP17-1085-44A11 , GoogleMaps MNP17-1089-44A15 GoogleMaps .

Description

Holotype

Length 80 mm, diameter 3.9 mm. Total number of segments 100. Color desert brown, uniformly pigmented. First dorsal pore starts from intersegmental furrow of 10/11. Prostomium tanylobic. aa: ab: bc: cd: dd = 1.89: 1: 1.96: 1.07: 9.97 on xii, aa: ab: bc: cd: dd = 3.14: 1: 2.57: 1.57: 13.43 on xxiv. Clitellum barrel-shaped, swelling of clitellum commenced from ½ xiii and extends up to xvi. Spermathecal pores on intersegmental region of 7/8, at b, slit-like aperture, surrounded by 4–5 small circular genital markings arranged in ring. Female pores paired on segment xiv, presetal at a. Male genital region hemispherical bowl-like, male genital orifices bivestibulate, pentagonal vestibula, apenile, between ab just beneath pear-shaped papillae. Genital markings paired on xvi post setal, at b, single median on xvii and 4–5 circular marking encircles spermathecal pore in vii–viii.

Septa 6/7/8/9 absent. Gizzard in viii. Intramural calciferous glands in xii. Intestine starts from xv. Lateral intestinal caeca in segment xxvi, small, ventrally directed. Typhlosole begins from xxvi. Ventral intestinal caeca 5 in number in segments xxx–xxxv. Supra-intestinal glands 3 pairs (first pair hidden underneath second one) in segment lxvii–lxx. Last pair of hearts in xiii. Holandric, testis sacs in x and xi, annular, seminal vesicles present in ix and xii, anterior one with distinct hexagonal chambers, posterior one extends up to xvi. Prostates in xvii–xxi, duct elongated, wide at posterior end. Penial setae two per battery, length 1.2–1.4 mm, width 0.037 mm, ornamented with triangular teeth in transverse rows, tip blunt, slightly bent on anterior region. Spermathecae bidiverticulate, one median and one lateral, diverticulum long tubular, helical, each diverticulum opens separately into duct with 5–6 seminal chambers, ampulla sac-like, duct short and wide. 4–5 small spheroidal genital marking glands present around spermathecal duct with one pair of sessile genital markings glands in xvi.

Variation

In paratype MNP17-1085-44A11, a paired genital marking present on xviii post setal, at b and absent on xvii.

Remarks

Eutyphoeus yangoupokpensis sp. nov., classified within the hastatus group ( Gates 1958), is characterized by holandric testes, bidiverticulate spermathecae, and spermathecal pores positioned at b. The species is grouped with other vestibulated members of the hastatus group, including E. tawi , E. marmoreus , E. lokchaensis sp. nov. and E. baronongini sp. nov. However, it is distinguished by the presence of lateral intestinal caeca, genital markings, and genital marking glands surrounding the spermathecal duct in segment vii ( Table 1 View Table 1 ).

DNA barcode

The holotype MNP17-1086-44A12 (process ID IEW1040-17) has been assigned the BIN number BOLD: ADL1713 based on COI barcode data. Eutyphoeus yangoupokpensis sp. nov. has a mean intraspecific divergence of 0.1% and a maximum intraspecific divergence of 0.15%. Its nearest neighbor species is Eutyphoeus tengnoupalensis sp. nov. with a nearest neighbor distance of 8.22 ( Table 2 View Table 2 ). All specimens of the novel species share the same BIN number.