Pheretima margaritata, Hong & James, 2011

Hong, Yong & James, Samuel W., 2011, New Species Of Pheretima, Pithemera, And Polypheretima (Clitellata: Megascolecidae) From Kalbaryo, Luzon Island, Philippines, Raffles Bulletin of Zoology 59 (1), pp. 19-28 : 20

Pheretima margaritata , new species

( Figs. 1 A–B)

along dorsal vessel; intestinal caeca simple, originating in xxvii, and extending anteriorly about to xxv, each consisting of a finger-shaped sac; typhlosole almost none. Hearts x–xiii esophageal; ix lateral, right side much larger.

Ovaries and funnels in xiii, spermathecae in vi–ix with nephridia on spermathecal ducts; spermatheca with small broad oval ampulla, flattened by gizzard, duct shorter than ampulla, iridescent diverticulum, seminal chamber eggshaped, with stalk longer than ampulla; several diverticula pass through septum to the anterior of the next segment. Male sexual system holandric, testes and funnels in ventrally paired sacs in x, xi. Seminal vesicles two pairs in xi, xii with dorsal lobes. Prostates in xvii–xviii, with short muscular duct entering central medial face of copulatory bursae without coelomic glands; copulatory bursa openings flanked anteriorly and posteriorly by circular pads; penis with long slit opening on one side.

Material examined. – Holotype: One clitellate ( NMA 4385 ), Philippines, Ilocos Norte Province, Pagudpud, Kalbaryo (18°33.65'N 127°57.83'E), 239 m, litter layers in the forest, coll. Y. Hong, A. Castillo & M. Levi, 3 Jun.2001. Four paratypes: 1 clitellate ( NMA 4393 ), 1 clitellate ( KUNHM), 1 clitellate ( NIBR), 1 clitellate ( ZRC): same data as for holotype.

Other material: 10 clitellates, 4 aclitellates ( KUNHM), Kalbaryo (18°30.94'N 120°54.52'E), 408 m, litter layer in the forest, 3 Jun.2001 .

Diagnosis. – Four pairs of spermathecal pores in 5/6–8/9; 0.4 mm openings of copulatory bursae, spermathecal pores and male pores 0.25–0.28 and 0.26 circumference ventrally apart, respectively.

Etymology. – The name margaritata is Latin for pearl, here referring to the color of the spermathecal diverticulum.

Description. – Dark brown dorsal pigment, segmental equators unpigmented around setae. Dimensions 85–148 mm by 3.0– 3.7 mm at segment x, 3.4–3.7 mm at xxx, 3.2–3.8 mm at clitellum, segments 83–96; body cylindrical in cross-section. Setae regularly distributed around segmental equators, numbering 24 at vii, 30 at xx; 4 between male pores, size, distance regular; setal formula AA:AB:YZ: ZZ = 4:2.5:4:7 at xiii. Clitellum annular in xiv–xvi; setae invisible externally.

First dorsal pore in 9/10, four pairs of spermathecal pores in 5/6–8/9, obvious bump inside segmental furrows, laterally placed, distance between spermathecal pores 2.8 mm (0.25– 0.28 circumference ventrally apart). Female pore single in xiv on 0.5 mm oval, 0.4 mm openings of copulatory bursae paired in xviii, distance between openings 2.4 mm (0.26 circumference ventrally apart). Genital markings absent.

Septa 5/6–7/8 thin, 8/9, 9/10 absent, 10/11, 11/12 slightly muscular, 12/13, 13/14 thin. Gizzard in viii–x, intestine enlarged from xv, medium paired lymph glands from xxviii Remarks. – Pheretima margaritata , new species, keys to the darnleiensis group in Sims & Easton (1972), composed of fifteen species, all of which were synonymized by Sims & Easton (1972). This species group is defined by having either four or five pairs of spermathecae, the last pair in segment ix, and the rare fifth in segment v. Pheretima margaritata , new species, differs from P. darnleiensis in having fewer setae per segment, fewer segments, generally shorter length (vs. restricted sense of P. darnleiensis , 155 mm), and consistently dark brown dorsal pigment, rather than sometimes unpigmented. The spermathecal diverticula are longer in Pheretima margaritata , new species, and the male and spermathecal pores are wider apart. Our examination of many of the species included in the synonymy of P. darnleiensis suggests that species-level differences have been ignored or discounted against the large number of spermathecae. The range possessed by P. darnleiensis sensu lato (Torres Strait to the Philippines; Borneo, Indonesia, Malaysia) could be either the result of an overly broad species concept or the consequence of human transport. We believe that this species was suspected of being a peregrine, at least within Southeast Asia, and for that reason the variations in size, coloration, and other characters were discounted. Certainly the original record on Darnley Island is outside the known natural range of Pheretima , so the suspicion was correct for that site. Even if there is a regional peregrine species embedded within P. darnleiensis we feel confident that 1) it does not include all the synonymized names and, 2) our material obtained from remote forested areas is native, not introduced. In any case, resolving the questions about the species divisions within P. darnleiensis will require a separate paper.

Figures

Fig. 1. Pheretima margaritata, new species: A, ventral view; B, spermathecae and diverticulum. Scale bars = 5 mm (A), 1 mm (B).