Metaphire narraensis, Aspe & Manasan & Manlavi & Patiluna & Sebido & Obusan & Simbahan & James, 2021

Aspe, Nonillon M., Manasan, Rafael Ethan, Manlavi, Albert B., Patiluna, Ma. Lotus E., Sebido, Maria Asela B., Obusan, Marie Christine M., Simbahan, Jessica F. & James, Samuel W., 2021, The earthworm fauna of Palawan, Philippines with description of nineteen new pheretimoid species (Clitellata: Megascolecidae), Journal of Natural History 55 (11 - 12), pp. 733-797 : 785-786

Metaphire narraensis sp. nov.

( Figure 20 )

Material examined

Holotype: adult ( WPU-A026 ), lower montane forest around Lake Atong in Victoria Peak area, municipality of Narra (9.300°N, 118.216°E), 700 m asl, Palawan Province, Philippines, coll. S. James, D. Flores, 31 October 2003 . Paratypes: two adults, one amputee ( WPU-A 027), same collection data as for holotype.

Etymology

The species is named after the municipality of Narra , Palawan, the type locality .

Diagnosis

Unpigmented worm with adult length 93–108 mm, diameter 3.5–5 mm; 113–117 segments; three pairs of spermathecal pores at 67/8/9; 43–52 setae on vii, 64–70 setae on xx; no setae between male pores; spermathecal pores 0.2–0.23 circumference apart ventrally; male openings 0.06–0.10 circumference apart ventrally; genital markings on 17/18 and 18/ 19 in line with male pores, transversely elliptical; prostates large in xv–xxi.

Description

Body unpigmented, equators unpigmented. Length 93–108 mm (n = 2 adults); diameter 4–5 mm at x, 3.5–4 mm at xx; body circular, 113–117 segments. First dorsal pore at 12/13, three pairs of spermathecal pores at 6/7/8/9, spermathecal pores 2.5–3 mm (0.2–0.23 circumference apart ventrally). Female pore single in xiv, openings of copulatory bursae paired in xvii, distance between openings 1–2 mm (0.06–0.10 circumference apart ventrally), no setae between male pore openings; male pores located deeply inside copulatory pouches in xviii. Clitellum annular, from xiv to xvi. Setae 43–52 on vii, 64–70 on xx, dorsal and ventral setal gaps present. Genital markings on 17/18 and 18/ 19 in line with male pores, transversely elliptical.

Septa 5/6–7/8 thin and membranous, 10/11–13/14 thin, 8/9/10 lacking. Dense tufts of nephridia on anterior faces of 5/6 and 6/7; nephridia in intestinal segments located mainly on body near septum/body wall junction. small gizzard in viii–x, oesophagus with low vertical lamellae x–xiii, intestinal origin in xiv; caeca simple, originating in xxvii, extending forward to xxi. Hearts in x–xiii, oesophageal; commissural vessels in vi, vii and ix lateral.

Ovaries and funnels free in xiii. Spermathecae paired, postseptal in vii, viii and ix, no nephridia on ducts. Each spermatheca with pyriform ampulla; slender, bulbous, muscular duct; single stalked diverticulum attached to the ental portion of the spermatheca; stalk slender, short, terminating in ovate receptacle. Male sexual system holandric; testes and funnels enclosed in paired sacs in x, xi; seminal vesicles xi and xii, each with digitate dorsal lobe; vesicles of xi enclosed in testes sac; vasa deferentia slender, free from body wall on way to ental end of prostatic ducts; prostates large in xvi–xxii; each prostate a single, dense, fan-shaped, racemose mass; coiling muscular duct terminating in the body wall in xviii; copulatory bursae not prominent; round genital marking glands present in xvii and xix.

Remarks

Metaphire narraensis sp. nov. belongs to the Me. peguana group of Sims and Easton (1972), characterised by having three pairs of spermathecal pores in 6/7–8/9 and postclitellar genital markings at 17/18 and 18/19. The species group includes Me. bahli Gates, 1945, Me. peguana Rosa, 1890 , Me. saigonensis Omodeo, 1957 and Me. doiphamon Bantaowong and Panha, 2016 in Bantaowong et al. 2016. Metaphire saigonensis has been placed in synonymy with Me. peguana (e.g. Blakemore 2002; Bantaowong et al. 2011; Prasankok et al. 2013). Metaphire peguana and Me. bahli have been recorded around South and Southeast Asia ( Blakemore 2016; Narayanan et al. 2019) and Me. bahli has also been recorded in Batangas and Negros Island, Philippines ( Thai and Samphon 1989). Recently, another species was added to the group, Me. haui Nguyen et al. 2020 from Vietnam. The new species differs from Me. bahli in having more space between spermathecal pores and between male pores (0.25 and 0.16 circumference apart ventrally) and in having more setae on vii (73+) and xx (91+). Metaphire peguana is larger (140–240 mm), has more setae on vii (56) and has more space between spermathecal pores (0.3 circumference apart ventrally) compared with the new species. Also, the genital markings of Me. peguana have paired rings with central aperture across 17/18 and 18/19. In contrast, Me. doiphamon is significantly larger (255 × 10 mm), has significantly more space between spermathecal pores (0.30 circumference apart ventrally) and between male pores (0.26 circumference apart ventrally), and has significantly more setae between male pores (21). Metaphire haui is similar to the new species in having an unpigmented body, but the former is relatively larger (107–165 × 5.3–5.9 mm), has 20–25 setae between male pores, has more space between male pores (0.3), has shorter caeca (xxvii–xxiv or xxv) and has relatively smaller prostates (xvii–xx). Another Metaphire species belonging to the Me. peguana group, collected from Los Baños City, Laguna, Philippines, was recently described (unpublished). This species differs from the new species in having less space between spermathecal pores (0.16 circumference apart ventrally), more space between male pores (0.16 circumference apart ventrally), 3–8 setae between male pores, shorter caeca (xxvii–xxiv) and prostate glands from xvi–xx.

Figures

Figure 20. Metaphire narraensis sp. nov. (a) External ventral view. (b) Internal dorsal view. (c) Spermathecae. Abbreviations: c, caecum,fp, female pores; gm, genital markings; gmg, genital marking glands; mp, male pores; p, prostate gland; s, spermathecae; sp, spermathecal pores; sv, seminal vesicles.