Pheretima floresi, Aspe & James, 2017

Aspe, Nonillon M. & James, Samuel W., 2017, Pheretimoid earthworms (Clitellata: Megascolecidae) from Mt. Apo, Mindanao Island, Philippines with description of eight new species, Raffles Bulletin of Zoology 65, pp. 357-372 : 360-361

Pheretima floresi , new species

( Fig. 1C )

Material examined. Holotype: adult ( NMP 4617 ), Brgy Baracatan , Davao City , Mt. Apo National Park (7°00′04″N, 125°21′55″E), 1,524 m asl, Mindanao Island, Philippines, coll. N. Aspe, A. Solis, D. Flores, 11–14 December 2003 . Paratypes: two adults ( ZRC. ANN 0070 ), same collection data as for holotype .

Etymology. The species is named in honor of Dr. Dante Flores, a fellow earthworm taxonomist and a friend, who joined the collecting activity at Mt. Apo.

Diagnosis. Small worm with adult length 48–67 mm; dorsum reddish brown, ventrum pale, segmental equator pigmented; one pair of spermathecal pores at 7/8; distance between spermathecal pores and male pores 0.21 and 0.20 circumference apart ventrally, respectively; spermatheca with an ovate ampulla and a large bulbous, muscular duct expanding ectally; racemose prostates extending from xvii–xx or xxi; penis lacking.

Description. Reddish brown dorsum, lighter ventrum, equators pigmented. Length 48–67 mm (n= 3 adults); diameter 3–3.5 mm at x, 3–4 mm at xx; body cylindrical in cross-section, tail tapering; 76–96 segments. First dorsal pore in 12/13. Spermathecal pores at 7/8, distance between spermathecal pores 2–2.3 mm (0.21 circumference ventrally apart). Female pore single in xiv. Openings of copulatory bursae paired in xviii, distance between openings 1.9–2.4 mm (0.20 circumference apart ventrally); 5 setae between openings. Clitellum annular, from xiv to xvi. Setae unevenly distributed around equators in some segments; 37 setae on vii, 45 setae on xx, dorsal setal gaps present, no ventral gaps. Genital markings lacking.

Septa 4/5/6, 8/9, 13/14 thin, 7/8, 10/11–12/13 muscular, 9/10 lacking. Dense tufts of nephridia on anterior faces of 5/6 and 6/7; nephridia of intestinal segments located mainly on body near septum/body wall junction. Large gizzard in viii–x, esophagus with low vertical lamellae x–xiii, intestinal origin in xv or xvi, caeca simple originating in xxvii, extending forward to xxiv, caeca may be folded up or down the intestine to a length equivalent to one segment. Typhlosole originating in xxvi, simple fold, about 1/8 lumen diameter. Intestinal wall with 35 longitudinal blood vessels. Hearts in x to xiii, esophageal; commissural vessels in vi, vii, and ix lateral; those in viii extending to gizzard.

Ovaries and funnels free in xiii. Spermathecae paired, postseptal in viii, with nephridia on ducts; each spermatheca with an ovate ampulla, large bulbous, muscular duct expanding ectally, diverticulum attached to the ental portion of the left face of the right spermathecal duct, and to right face of the left spermathecal duct, stalks thin, short, terminating in elongated receptacles wider at distal end. Male sexual system holandric, testes and funnels enclosed in paired sacs in x, xi; seminal vesicles in xi, xii, each with a digitate dorsal lobe; vesicles of xi enclosed in testis sacs; vasa deferentia slender, free from body wall en route to ental end of prostatic ducts; prostates in xvii to xx or xxi; each prostate a single, dense, racemose mass, with three lobes; short, muscular duct entering posterior area of copulatory bursa. Copulatory bursae ovate in xvii–xviii; coelomic surfaces muscular, secretory diverticula lacking; two pads present on roof, pad lacking on floor; penis lacking.

Remarks. Pheretima floresi , new species belongs to the P. sangirensis species group of Sims & Easton (1972), characterised by having spermathecal pore(s) at 7/8 and having no penial sheaths in the copulatory bursae. Members of the sangirensis group have a holandric male system; the copulatory bursae are simple, and some species have short, conical penes. Blakemore (2007) acknowledged three valid subspecies in P. sangirensis : P. s. sangirensis ( Michaelsen, 1891) ; P. s. crassicystis ( Michaelsen, 1896); and P. s. chica ( Michaelsen, 1896). To date, there are 30 species members of the P. sangirensis group ( Aspe & James, 2016), including the new species described here. Molecular phylogenetic studies conducted by James (2005b) and Aspe et al. (2016) showed that members of the P. sangirensis group included in their respective studies are monophyletic.

Pheretima floresi is similar to P. s. chica Michaelsen, 1896, P. mariae ( Hong & James, 2008a) , P. misamisensis ( Aspe & James, 2014) , P. wati ( Aspe & James, 2014) , P. longiprostata ( Aspe & James, 2014) , and P. solisi , new species in relative size (37–75 mm × 2–4 mm) and in having pigmentation all over the dorsum including the segmental equators. However, P. s. chica (0.25 circumference apart) and P. misamisensis (0.3 circumference apart) have wider distance between the spermathecal pores and P. mariae (0.04 circumference apart), P. wati (0.17 circumference apart), P. longiprostata (0.16 circumference apart) and P. solisi (0.18 circumference apart) have closer spermathecal pores. With regards to the distance between male pores, P. misamisensis ’ (0.23 circumference apart) are wider while those in P. mariae (0.09 circumference apart), P. wati (0.08 circumference apart), P. longiprostata (0.16 circumference apart), and P. solisi (0.15 circumference aprt) are closer. Mating is effective when two copulating individuals have compatible size and compatible distance between the spermathecal pores and between the male pores. Compared with the new species, P. wati has more setae (59–71 in vii, 52–60 in xx), P. mariae has fewer setae (32 in vii, 31 in xx), P. s. chica has more post-clitellar setae (>60), and P. misamisensis has more pre-clitellar setae (42–51 in vii). The prostates are more extensive and the copulatory bursae are larger in P. misamisensis (xvi–xxi and xvii–xix, respectively), P. wati (xv–xxii and xvii–xxi, respectively) and P. longiprostata (xv–xxiii and xvii–xx, respectively) compared with the new species. Pheretima floresi also differs in terms of the form of the spermathecae: P. mariae has small lenticular spermathecal ampulla, with diverticulum with short duct terminating in small ovate receptacle; P. s. chica and P. misamisensis both have reniform spermathecae, with P. s. chica ’s diverticulum with long stalk originating ectally and P. misamisensis ’ diverticulum terminating in blunt ovate receptacle; P. wati has pyriform spermathecal ampulla, with diverticulum with short duct terminating in small ovate receptacle; P. longiprostata has transversely place oval spermathecal ampulla, with short thick muscular duct, and with diverticulum terminating in small ovate receptacle; and P. solisi has round ampulla and very large bulbous, muscular duct, with diverticulum with long convoluted stalk terminating in small ovate receptacle. In addition, P. s. chica, P. misamisensis , P. longiprostata , and P. mariae have penes while the new species has none. No other species in the P. sangirensis group closely resemble P. floresi .

Figures

Fig. 1. A, Diagrammatic ventral view of Amynthas apongensis, new species showing the spermathecal pores (sp), clitellum (cl), male pores (m), and the pattern of the genital markings (gm). Schematic drawings of the internal morphology in dorsal view: B, A. apongensis, new species; C, Pheretima floresi, new species; D, P. baracatanensis, new species; E, P. solisi, new species. Abbreviations: s, spermatheca; h, heart; p, prostate gland; cb, copulatory bursa; c, caecum. Scale bars = 5 mm.