Metaphire peguana peguana (Rosa, 1890)

(Figure 4, Table 3)

Perichaeta peguana Rosa 1890: 113, figs. 6–8; Beddard 1895: 403.

Amynthas (Pheretima) peguanus – Michaelsen 1899: 7.

Pheretima peguana – Michaelsen 1900: 292; Gates 1939: 102, 1972: 207; Omodeo 1956: 325; Thai 1983: 124; Thai 1987: 7, 2000: 309; Thai & Do 1989: 77; Nguyen & Tran 2008: 185; Thai et al. 2004: 759; Huynh 2005: 88; Nguyen et al. 2010: 114, 2011: 1025; 2012: 146; Nguyen & Nguyen 2010: 123; Nguyen 2014: 109.

Amyntas peguanus Beddard 1900: 628 .

Pheretima peguanna (sic!) – Huynh & Nguyen 2004: 116.

Metaphire peguana – Sims & Easton 1972: 239; Easton 1981: 58; Blakemore 2002: 207, 2008: 78, 2016: 7; Shen & Yeo 2005: 14; Sarkar et al. 2012: 178; Nguyen et al. 2016: 63; 2020: 8.

Metaphire peguana peguana – Nguyen et al. 2017a: 98, 2021a: 17, 2021c: 105; Lam et al. 2021: 17701.

Type locality. Myanmar (Rangoon) (Rosa 1890)

Type material. Natural History Museum Giacomo Doria (44037), Italy .

Diagnosis. Body cylindrical, length 81–143 mm, diameter 3.7–6.3 mm, segments 60–157. Prostomium epilobous. First dorsal pore at 12/13 or 13/14. Three pairs of spermathecal pores in ventrolateral intersegments 6/7/8/9, bithecate. Two pairs of disc–shaped genital markings on 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 only present 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 is found in leaf litter in various types of habitats in Southern Vietnam .

Distribution. French Guiana (Csuzdi & Pavlíček 2010), India, Thailand (Blakemore et al. 2006; Prasankok et al. 2013), Myanmar, Malaysia, Indonesia, Japan (Gates 1972; Ishizuka 1999; Ng et al. 2017), Singapore (Shen & Yeo 2005), Cambodia, Laos (Thai & Samphon 1989), Bangladesh (Sarkar et al. 2012), Australia (Easton 1982), and commonly found in Vietnam (Nguyen et al. 2016, 2021a, 2021c; Lam et al. 2021) (Fig. 3).

Remarks. Metaphire peguana peguana is the typical form and the one found outside of Southeast Asia along with M. bahli . Although this subspecies has a relatively stable morphology with genital markings paired in 17/18 and 18/19, there was still a slight difference throughout populations in Vietnam. Vietnamese specimens have a greater ventral distance between spermathecal pores than other populations (0.33–0.50 vs. 0.28–0.29 body circumference) (Rosa 1890; Gates 1972; Bantaowong et al. 2011). In addition, the genetic distance among Vietnamese specimens was from 3% (Table 4) while that from Thailand and Malaysia is about 4.8% (Prasankok et al. 2013; Jeratthitikul et al. 2017; Ng et al. 2017). The genetic distance between M. peguana peguana and other Metaphire species from 15.1%±1.6% (with M. bahli (type II)) to 23.5%±2.1% (with M. grandiverticulata) (Table 4).