Pheretima hamadryades, 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 : 757-759

Pheretima hamadryades sp. nov.

( Figure 9 )

Material examined

Holotype: adult ( WPU-A012 ), arboreal, on the ridge of Mt. Mantalingahan in Brgy. Marinana , municipality of Brooke’s Point, (8.750°N, 117.683°E), 930 m asl, Palawan Province, Philippines, coll. S. James, D. Flores, 25 October 2003 . Paratypes: two adults ( WPU-A 013), same collection data as for holotype.

Etymology

ἉμαδρυαδΕς (Greek) Hamadryades: meaning together with trees, being one of the types of Dryads, or nature spirits of Greek tradition.

Diagnosis

Brown worm with adult length 55–78 mm, diameter 2.5–5 mm; 77–108 segments; four pairs of spermathecal pores at 5/6–8/9; 32–59 setae on vii, 47–58 setae on xx; 8–11 setae between male pores; spermathecal pores 0.19–0.22 circumference apart ventrally; male openings 0.18–0.22 circumference apart ventrally; genital markings lacking; prostates small in xvi–xviii; penis lacking.

Description

Brown, equators pigmented. Length 55–78 mm (n = 3 adults); diameter 2.5–5 mm at x, 3–5 mm at xx; body circular in cross section, tail tapering; 77–108 segments. First dorsal pore at 12/13, four pairs of spermathecal pores at 5/6–8/9, spermathecal pores 1.5–2.1 mm (0.19–0.22 circumference apart ventrally). Female pore single in xiv, openings of copulatory bursae paired in xviii, distance between openings 2 mm (0.18–0.22 circumference apart ventrally), 8–11 setae between openings. Clitellum annular, from xiv to xvi. Setae unevenly distributed around equators in some segments; 32–59 setae on vii, 47–58 setae on xx, dorsal and ventral setal gaps present. Genital markings lacking.

Septa 5/6–7/8 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. Gizzard in ix–x, oesophagus with low vertical lamellae x–xiii, intestinal origin in xiv; caeca simple, originating in xxvii, extending forward to xxii. Hearts in x–xiii, oesophageal; commissural vessels in vi, vii and ix lateral.

Ovaries and funnels free in xiii. Spermathecae paired in vi–ix, with many nephridia on ducts. Each spermatheca with round to ovate ampulla; short, bulbous, muscular duct; single stalked diverticulum attached to the ental portion of the spermatheca; stalk short, terminating in small, ovate receptacle. Male sexual system holandric; testes and funnels enclosed in paired sacs in x, xi; seminal vesicles xi, 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; small prostates in xvii–xviii; each prostate a single, dense, racemose mass; short, muscular duct entering posterior margin of copulatory bursa. Copulatory bursae round, small in xviii; penis lacking.

Remarks

Pheretima hamadryades sp. nov. belongs to the Ph. darnleiensis species group of Sims and Easton (1972). Among the members of the Ph. darnleiensis group, the new species is relatively similar in its small size to Ph. potonganensis , Ph. tabukensis and Ph. thaii ( Table 1). However, Ph. potonganensis has fewer setae between male pores (4), has fewer setae on xx (28–44) and has longer caeca (xxvii–xx); Ph. tabukensis has more space between spermathecal pores (0.23–0.24), has fewer setae between male pores (6), has fewer setae on xx (23–36) and has shorter caeca (xxvii–xxv); and Ph. thaii has significantly more space between spermathecal pores (0.5), has significantly fewer setae between male pores (3), and has significantly fewer setae on vii (16) and xx (24). In addition, the latter three species have a penis while the new species lacks a penis.

Figures

Figure 9. Pheretima hamadryades sp. nov. (a) External ventral view. (b) Internal dorsal view. (c) Spermathecae. Abbreviations: c, caecum; cb, copulatory bursa; fp, female pores; mp, male pores; p, prostate gland; s, spermathecae; sp, spermathecal pores; sv, seminal vesicles.