Polypheretima jenniferae, 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 : 766-767

Polypheretima jenniferae sp. nov.

( Figure 12 )

Material examined

Holotype: adult ( WPU-A018 ), near the Elephant Cave in Brgy. Cabayugan , Puerto Princesa City, (10.133°N, 118.866°E), 27 m asl, Palawan Province, Philippines, coll. E. Manasan, A. Manlavi, 15 March 2019 . Paratypes: three adults ( WPU-A 019), same collection data as for holotype.

Etymology

The species name was given in honour of the first author’s spouse, Jennifer, who has always assisted and supported him in his research works.

Diagnosis

Brown worm with adult length 161–198 mm, diameter 3.5–5.5 mm; 161–198 segments; no spermathecal pores; 43–64 setae on vii, 53–74 setae on xx; 7–14 setae between male pores; male openings 0.27 circumference apart ventrally; paired genital markings widely spaced on xix–xxiii, in line with male pores; spermathecae lacking; large prostates in xvi–xxi.

Description

Light brown dorsum, pale ventrum, segment equators unpigmented. Length 161–198 mm (n = 4 adults); diameter 3.5–5.5 mm at x, 3.2–4.5 mm at xx; body circular in cross section, tail tapering; 160–218 segments. First dorsal pore at 12/13, spermathecal pores lacking. Female pore single in xiv, openings of male pores paired in xviii, distance between pores 3.5–3.9 mm (0.27 circumference apart ventrally), 7–14 setae between pores. Clitellum annular, from xiv to xvi. Setae unevenly distributed around equators in some segments; 43–64 setae on vii, 53–74 setae on xx, dorsal setal gaps present, ventral setal gaps present. Paired genital markings widely spaced on xix–xxiii, in line with male pores.

Septa 4/5–7/8 membranous, 8/9 and 10/11–13/14 thin, 9/10 lacking. Dense tufts of nephridia on anterior faces of 4/5, 5/6 and 6/7; nephridia of intestinal segments located mainly on body near septum/body wall junction. Large gizzard in ix–x, oesophagus with low vertical lamellae x–xiii, intestinal origin in xv, caeca lacking. Hearts in x–xiii, oesophageal; commissural vessels in vi, vii and ix lateral.

Ovaries and funnels free in xiii. Spermatheca lacking. Male sexual system holandric, testes and funnels enclosed in paired ventral sacs in x and xi; seminal vesicles in xi and xii; pseudovesicles in xiii; vasa deferentia slender, free from body wall on way to ental end of prostatic ducts; large prostates in xvi–xxi, each prostate racemose, compact; long, muscular duct from lateral margin of prostate makes a coil and widens towards body wall, then narrows slightly just before body wall; copulatory bursae shallow.

Remarks

Polypheretima jenniferae sp. nov. belongs to the Po. elongata species group of Easton (1979). Among the members of Po. elongata group, Po. jenniferae sp. nov. is relatively similar to Po. victoriaensis sp. nov. and Po. irawanensis sp. nov. in pigmentation,in length and in the number of segments ( Table 2). However, the new species is thinner (3.2–5 mm vs 6–8.5 mm in Po. victoriaensis sp. nov. and Po. irawanensis sp. nov.), has fewer setae on vii and xx (43–64, 53–74 vs 91–98, 77– 82 in Po. victoriaensis sp. nov. and Po. irawanensis sp. nov.), has genital markings from xix to xxiii (vs from xix to xxiii in Po. victoriaensis sp. nov. and Po. irawanensis sp. nov.), and has prostates in xvi–xxi (vs xv–xix in Po. victoriaensis sp. nov. and xvii–xviii in Po. irawanensis sp. nov.). Also, the new species has more space between male pores (0.27 circumference apart ventrally) compared with Po. irawanensis sp. nov. (0.22 circumference apart ventrally). In addition, the new species has no spermathecae, in contrast to the two latter species.

Polypheretima jenniferae sp. nov. is found to have high survival and reproduction rates, making it an ideal candidate for use in vermicomposting. The absence of spermathecae in Po. jenniferae sp. nov. suggests parthenogenetic reproduction in the species ( Gates 1972). Earthworm species that reproduce parthenogenetically have the advantage of growing faster in number as they do not necessarily require a mate for them to reproduce. This is true for the pantropical Pontoscolex corethrurus and the species popularly used for vermicomposting in the Philippines, Eudrilus eugenieae . Other individuals of Po. mindanaoensis and Po. sahlani , which are also members of the Po. elongata group, have also been recorded as having no spermathecae. Polypheretima jenniferae sp. nov. is currently being tested for its ability to compete with E. eugenieae in in growth, survival and reproduction at the Western Philippines University in Puerto Princesa City, Palawan. The microbiota and the enzymatic activities in its gut are also currently being tested, in the University of the Philippines in Diliman, Quezon City, for their potential to degrade the plastic in disposable diapers.

Figures

Figure 12. Polypheretimajenniferae sp.nov.(a) External ventral view.(b) Internal dorsal view.Abbreviations: fp, female pores; gm, genital markings; mp, male pores; p, prostate gland; sv, seminal vesicles.