Pheretima malindangensis, Aspe, Nonillon M. & James, Samuel W., 2014

Aspe, Nonillon M. & James, Samuel W., 2014, New species of Pheretima (Oligochaeta: Megascolecidae) from the Mt. Malindang Range, Mindanao Island, Philippines, Zootaxa 3881 (5), pp. 401-439 : 416-418

Pheretima malindangensis n. sp.

( Figs 2 E, 5A. Table 2)

Material examined. Holotype: adult (NMA 4513) Brgy Sibucal, Oroquieta City, Misamis Occidental Province, Mt. Malindang Range (8º19'31"N, 123º38'02"E), 991 m asl., Mindanao Island, Philippines, coll. Nonillon Aspe, M. Lluch, and J. Adeva, Feb. 18–25, 2004. Paratypes: 2 adults (NMA 4536); one adult ( ZRC.ANN.0020), same collection data as for holotype.

Etymology. The species is named after Mt. Malindang National Park.

Diagnosis. Small worm with adult length reaching 60–81 mm, purplish brown; distance between spermathecal pores and male pores relatively short; spermathecal ampulla small, rounded, rectangular, with large, bulbous, muscular duct; gizzard large, extending from viii to xi; intestinal origin in xvi; hearts in xi to xiii, absent in x; elongate prostate glands extending from xvi to xxi; copulatory bursae large and ovate extending from xvii to xx; caeca extending from xxvii to xxiii. Penial setae present on penial body of copulatory bursae.

Description. Living animals with dorsum dark purplish-brown anteriorly, fading to medium brown posteriorly; equators non-pigmented; ventral side non-pigmented; clitellum gray. Length 60–81 mm (n= 3 adults); diameter 4.0– 4.5 mm at x, 4.0–5.0 mm at xx; body cylindrical in cross-section, tail blunt; 69–96 segments. First dorsal pore 12/13; paired spermathecal pores at 7/8, 0.16 circumference apart ventrally, with prominent internal ridges leading into each pore. Female pore single in xiv; openings of copulatory bursae paired in xviii, 0.11 circumference apart ventrally, no setae between openings. Clitellum annular, extending from xiv to xvi. Setae evenly distributed, 43–47 setae on vii, 50–57 on xx, no dorsal gap, ventral gap present.

Septa 5/6/7/8 and 10/11–13/14 slightly muscular, 8/9/10 absent. Dense tufts of nephridia on anterior faces of 5/ 6 and 6/7; nephridia of intestinal segments mainly on body wall at anterior and posterior faces of septa, located at septum/body wall junction.

Large gizzard extending from viii to xi; esophagus with circumferential lamellae within xi and xii, with digitiform internal texture from xiii to xiv; intestine originates in xvi; caeca originate in xxvii, extending forward to xxiii, with serrate ventral margins; typhlosole a simple fold about 1/6 lumen diameter, originating in xxvii; intestinal wall with 30 longitudinal blood vessels.

Hearts in xi to xiii, esophageal, absent in x; commissural vessels vi, vii, and ix lateral; viii extending to gizzard; supra-esophageal vessel extends from x to xiii; extra-esophageal vessels join ventral esophageal wall in x, receive efferent parieto-esophageal vessels in xiv.

Ovaries and funnels free in xiii; paired spermathecae post-septal in viii, with nephridia on ducts; ampulla small, rounded, rectangular; spermathecal duct large, bulbous, muscular, its wall thick and corrugated; single stalked diverticulum attached to posterior face of muscular bulb of duct, terminating in bean-shaped receptacle attached by its end, stalks longer than receptacle, increasing in diameter ectally. Two spermatophores present in each ampulla. Male sexual system holandric; testes and funnels enclosed in unpaired ventral sacs in x and xi; seminal vesicles in xi and xii, each with short dorsal lobe; vasa deferentia slender, free from body wall, passing around anterior lateral face of copulatory bursae en route to ental end of prostatic ducts; each prostate racemose, 4 or 5 lobed, from xvi to xxi, wrapped around lateral margin of copulatory bursa; muscular duct enters dorsal face of copulatory bursa just posterior of center. Ductlet from anterior prostatic lobes joins vas deferens, posterior ductlet at common junction with muscular prostatic duct. Large, ovate copulatory bursae extending from xvii to xx, broader in anterior portion; coelomic surface of copulatory bursa muscular, secretory diverticula lacking. Floors of bursae with anterior and posterior pads flanking opening, gutter leading from opening up to base of penis; roofs with single angular posterior pad and large anterior glandular mass. Large blocky centrally placed penis bearing 5 penial setae; copulatory bursae lack penial sheaths.

Remarks. Pheretima malindangensis n. sp. belongs to the P. sangirensis group of Sims & Easton (1972). It is unique in having setae on the penial body. It differs from all subspecies of P. sangirensis in having closer spacing between the spermathecal pores and between the male pores, in lacking a dorsal setal gap (also lacking in P.s. crassicystis ), and in having a ventral setal gap; in the origin of intestine; and in lacking hearts in x ( Table 2). It is similar in size and coloration to P. wati n. sp., P. longiprostata n. sp., and P. nolani n. sp (see descriptions below), but differs (apart from the setae on the penis) in the male pore spacing, in lacking a dorsal setal gap, and having a ventral setal gap; in the number of hearts, the origin of intestine, and shape of spermathecae; and in the size, shape, and position of the prostates and copulatory bursae ( Table 2). Pheretima malindangensis does not closely resemble any species in the sangirensis group at Mt. Kitanglad (James 2004).

Occurrence. Pheretima malindangensis was found in Brgys Sibucal and Lake Duminagat, at elevations of 902–2027 m asl, with more individuals found in Brgy Sibucal. It occurred in the soil and above ground in substrates such as rotting logs (Table 1).

Figures

FIGURE 2. Photographs of living Pheretima worms in dorsal view, showing coloration. (A) P. maculodorsalis n. sp.; (B) P. tigris n. sp.; (C) P. immanis n. sp.; (D) P. longigula n. sp.; (E) P. malindangensis n. sp. Scale bars: A – D, 5 cm; E, 3 cm.