Pheretima lluchi, 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 : 426-428

Pheretima lluchi n. sp.

( Fig. 7 C, Table 3 )

Material examined. Holotype: (NMA 4525) 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, Nolan Aspe, M. Lluch, and J. Adeva, Feb. 18–25, 2004. Paratypes: three adults (NMA 4544), same collection data as for holotype. Other paratypes: two adults ( ZRC.ANN.0026), Brgy Lake Duminagat, municipality of Don Victoriano, Misamis Occidental Province, Mt. Malindang Range (8º17'55"N, 123º37'01"E), 1357 m asl., coll. Nonillon Aspe and J. Adeva, Oct. 9–15, 2003.

Etymology. The species is named after Myko Lluch, who assisted in the fieldwork.

Diagnosis. Brown, slender worm reaching 104–135 mm in adult length; four pairs of spermathecal pores in 5/ 6 to 8/9; distance between spermathecal pores same as that between male pores; first dorsal pore in 13/14; intestinal origin in xvi; prostates in xviii to xx; caeca from xxvii to xxiv.

Description. In living animals, dorsum brown, darker anteriorly; equators pigmented. Length 104–135 mm (n= 6 adults); diameter 4 mm at x, 4.5 mm at xx; body cylindrical in cross-section, tail blunt; 71–104 segments. First dorsal pore at 13/14; spermathecal pores at 5/6/7/8/9, 0.2 circumference apart ventrally; female pore single in xiv; openings of copulatory bursae paired in xviii, 0.2 circumference apart ventrally, 5–6 setae between openings. Clitellum annular, extending from xiv to xvi. Setae evenly distributed, 29–30 setae on vii, 39–45 setae on xx, no dorsal or ventral gaps.

Septa 5/6/7/8 and 10/11–13/14 muscular, 8/9/10 absent. Dense tufts of nephridia on anterior faces of 5/6 and 6/ 7; nephridia of intestinal segments located mainly on body wall at anterior and posterior faces of septa, at septum/ body wall junction. Large gizzard in ix to x; esophagus with circumferential lamellae from xi to xiii, pebbly texture in xiv; intestine originates in xvi; caeca originate in xxvii, extend forward to xxiv, simple, with smooth ventral margin; typhlosole rudimentary; intestinal wall with 28–30 longitudinal blood vessels.

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

Ovaries and funnels free in xiii; ovisacs lacking; spermathecae 4 pairs in vi to ix, with many nephridia on ducts; each spermatheca with ovate to spherical ampulla and short, thick, non-muscular duct; stalked diverticulum attached to lateral face of duct at middle, terminating in short, banana-shaped receptacle; stalk about as long as receptacle. Spermatophores lacking. Male sexual system holandric; testes and funnels enclosed in paired sacs in x and xi; seminal vesicles in xi and xii, lacking dorsal lobes; vasa deferentia slender, free from body wall en route to ental end of prostatic ducts; each bilobed prostate racemose in xviii to xix; short, muscular duct enters apex of copulatory bursa in xviii, ectal half of duct attached to copulatory bursa surface. Coelomic surface of copulatory bursa muscular, secretory diverticula lacking; bursa a low, ovate dome; conical penis with thick base projects from bursa roof.

*Description from Fletcher (1887) and Hong & James (2011b); excluding the description by Blakemore et al. (2007).

Remarks. Pheretima lluchi n. sp. belongs to the P. darnleiensis group of Sims & Easton (1972). It differs from P. darnleiensis in the location of the first dorsal pore, in the number of setae between male pores, in the origin of intestine, and in the length of the prostates ( Table 3 ). Pheretima lluchi furthermore differs from Perichaeta belli ( Rosa, 1898) and P. benguetensis ( Beddard, 1912) , which Sims & Easton (1972) synonymized with P. darnleiensis , in color and pigmentation pattern (brown bands in Pe. belli ; purplish blue pigmentation in P. benguetensis ), in the number of setae (more in Pe. belli ; 40), in the location of the first dorsal pore (7/ 8 in P. benguetensis ), and in the extent of the caeca (xxvi–xxv in Pe. belli ; xxv–xx in P. benguetensis ), among other characters. Pheretima lluchi is similar to P. adevai n. sp. in the size and origin of the gizzard, but the two species differ in the location of the first dorsal pore, the origin of the intestine, the lengths of the caeca and prostates, and markedly in the spacings of the spermathecal and male pores ( Table 3 ). Pheretima lluchi is similar to P. margaritata and P. pugnatoris in size, septal arrangement, and the origin of the gizzard, but differs from them in the number of setae on vii (24 in P. margaritata ; 16–19 in P. pugnatoris ), the location of the first dorsal pore (9/ 10 in P. margaritata ; 11/ 12 in P. pugnatoris ), the origin of the intestine (xv in the two latter species), the length of the caeca and prostates (xxvii–xxv and xvii–xviii, respectively in P. margaritata , and xxvii–xxiv and xvii–xix, respectively in P. pugnatoris ), and markedly in the spacings of the spermathecal and male pores (0.25–0.28 and 0.26 circumference apart, respectively, in P. margaritata ; 0.26–0.29 and 0.17–0.18 in P. pugnatoris ). Other Philippine Pheretima species with more than one pair of spermathecae are P. castilloi James et al., 2004 ; P. c a l l os a James, 2004; and P. philippina Rosa, 1891 . These species differ from P. lluchi in size and in having 3 pairs of spermathecae (5/6–7/ 8 in P. castilloi ; 6/7–8/ 9 in P. callosa and P. philippina ).

Occurrence. Pheretima lluchi was uncommon, comprising 1.3% of the total individuals found on plots; we detected it in Brgys Sibucal and Lake Duminagat, at elevations of 902–2027 m. It inhabited both the soil and substrates above ground, such as rotten logs. The species was not observed at lower elevations (Table 1).

Figures

FIGURE 7. (A) Diagrammatic ventral view of polythecal Pheretima adevai, showing the spermathecal pores (sp), clitellum (cl), and male pores (m). (B – D) Schematic drawings of the internal morphology of Philippine Pheretima species, in dorsal view: (B) P. a de v ai n. sp.; (C) P. lluchi n. sp.; (D) P. potonganensis n. sp. Abbreviations: s, spermatheca; h, heart; p, prostate gland; cb, copulatory bursa; c, caecum. Scale bars: B – D: 5 mm.

Tables

TABLE 3. Comparison of species in the Pheretima darnleiensis group at Mt. Malindang.

Character	Pheretima darnleiensis * Fletcher, 1887	Pheretima adevai n. sp.	Pheretima lluchi n. sp.	Pheretima potonganensis n. sp.
Body pigmentation	?	Dorsally pigmented all over	Dorsally pigmented all over	Dorsally pigmented all over
Length	75–170	110–131	104–135	63–89
Location of spermathecal pores	5/6/7/8/9	5/6/7/8/9	5/6/7/8/9	5/6/7/8/9
First dorsal pore	11/12	12/13	13/14	12/13
Setae vii; xx	12–35; 38–45	32–37; 36–39	29–30; 39–45	32–34; 28–44
Setae bet. male pores	12	3–7	5–6	4
Sper. pores spacing	0.2	0.25	0.2	?
Male pores spacing	0.2	0.16	0.2	0.17
Setal gaps D; V	?; -	-; -	-; -	-; +
Septa in 5/6–13/14	+ or - in 8/9; - in 9/10	- in 9/10	- in 8/9/10	+
Origin of gizzard	ix/viii	ix	ix	ix
Origin of intestine	xv	xv	xvi	xiv
Caeca	xxvii–xxiv	xxvii–xxiii	xxvii–xxiv	xxvii–xx
Origin of typhlosole	?	xxvii	xxvii/xviii	xxvii
Intestinal vessels	?	34–38	28–30	26
Location of hearts	x–xiii	x–xiii	x–xiii	x–xiii
Prostate glands	xviii–xix	xviii–xix	xviii–xx	xvii–xix
Copulatory bursae	?	xviii	xviii–xix	xviii–xix
Penes	+	+	+	+