Metaphire nhuongi Nguyen 2016
Creators: name: Nguyen, Tung T.
name: Lam, Dang H.
name: Nguyen, Anh D.
Publisher: name: Zenodo
Year: 2023
Subjects: Biodiversity
Taxonomy
Animalia
Annelida
Clitellata
Crassiclitellata
Megascolecidae
Metaphire
Metaphire nhuongi

description: Metaphire nhuongi Nguyen, 2016
(Figure 13, Table 3)
Metaphire nhuongi Nguyen 2016: 442, fig. 2; Nguyen et al. 2021c: 105.
Pheretima sp. 10 – Nguyen et al. 2012: 146.
Pheretima sp. 14 – Nguyen 2013: 85, 2014: 112.
Type locality. Vietnam (An Giang: Co To mountain) (Nguyen 2016)
Type material. Laboratory of Zoology, Department of Biology, Can Tho University (EW.024.h01, EW.024. p02, EW.024.p03), Vietnam.
Diagnosis. Body cylindrical, large-medium size, length 213–339 mm, diameter 8.9–9.5 mm, segments 120–148. Prostomium epilobous. First dorsal pore at 12/13. Four pairs of spermathecal pores in ventrolateral intersegments 5/6/7/8/9, bithecate. Two pairs of ellipsoid genital markings in intersegments 17/18 and 18/19, each with a small opening at the center. Male pores located inside copulatory pouches in xviii. Septum 10/11 present only ventrally. Intestinal caeca simple. Holandric, testis sacs separated. Accessory glands coelomic, strongly covered by muscularwalled bursae in 17/18 and 18/19.
Habitat. The species found in the depth of 15–20 cm in soils of natural forests or in perennial mango gardens in a mountain foot. They excreted their feces to create columns emerging from the soil surface (Nguyen 2016).
Distribution. Only recorded in Vietnam (An Giang: Co To, Phu Cuong, and Ta Pa mountains) (Fig. 3).
Remarks. There were no significant morphological differences between individual found.
The K2P intraspecific genetic distance was 1.3%±0.3%. The genetic distance between M. nhuongi and other Metaphire species was from 17.6%±1.8% (with M. dorsomultitheca) to 22.9%±2.1% (with M. grandiverticulata) (Table 4).
Key to species of Metaphire peguana species-group
1. – Bithecate, one pair of spermathecae per segment.......................................................... 2 – Polythecate, numerous spermathecae per segment......................................................... 6
2. – Four pairs of spermathecal pores in 5/6/7/8/9...................................................... M. nhuongi – Three pairs of spermathecal pores in 6/7/8/9............................................................... 3
3. – Genital markings paired in vi–ix............................................................. M. doiphamon – Genital markings absent in the spermathecal region......................................................... 4
4. – Spermathecal pores located ventrally. Ventral distance between spermathecal pores 0.15–0.29 body circumference. M. bahli – Spermathecal located more laterally. Ventral distance between spermathecal pores 0.33–0.50 body circumference....... 5
5. – The openings of genital markings small, slit-shaped or ellipsoid-shaped, in post-setal and pre-setal positions in xvii and xix, respectively....................................................................... M. peguana laisonensis – The openings of genital markings disc-shaped, in 17/18 and 18/19, expanding to reach two setal rings. M. peguana peguana
6. – Spermathecal pores located in ventral intersegments 6/7/8/9. Genital markings paired in 17/18 and 18/ 19 M. kiengiangensis – Spermathecal pores located in dorsal intersegments 7/8/9. Genital markings opening on the walls of the copulatory pouches M. dorsomultitheca
description: Published as part of Nguyen, Tung T., Lam, Dang H. & Nguyen, Anh D., 2023, A revision of the Metaphire peguana species-group (Oligochaeta: Megascolecidae) from Vietnam, pp. 113-135 in Zootaxa 5255 (1) on pages 131-132, DOI: 10.11646/zootaxa.5255.1.15, http://zenodo.org/record/7744555