Pheretima sorsogonensis Hong & James, 2025

Pheretima sorsogonensis Hong & James sp. nov.

Fig. 2 View Figure 2

Type material.

Holotype. Philippines • 1 clitellate; Sorsogon Province, Bulusan Volcano Natural Park , near a lake; 12°45.32'N, 124°04.34'E; 350–400 m a. s. l.; 3 May 2001; S. W. James leg.; NMA 4803 GoogleMaps .

Additional material examined.

Philippines • 2 clitellates, 1 aclitellate; same data as for holotype GoogleMaps .

Type locality.

Philippines, Sorsogon Province, Bulusan Volcano Natural Park, near a lake ( 12°45.32'N, 124°04.34'E), 350–400 m a. s. l.

Diagnosis.

Pheretima with one pair of spermathecal pores in 7 / 8 at 7 th setal line, equatorial unpigmented stripes, intestinal origin in XVI, spermathecae in VII, septa 8 / 9 / 10 absent, all setal counts greater than 40, 4–6 setae between male pores, and seminal vesicle dorsal lobes apically attached, elongate with wide heads.

Description.

Medium light-brown dorsal pigment, with thin pale zones at setal rings. Dimensions 56–68 mm by 3.0–3.5 at segment X, 3.3–3.4 mm at XXX, 3.0– 3.5 mm at clitellum, segments 97–108; body circular in cross-section. Setae numbering 39–42 at VII, 45–50 at XX; 4–6 between male pores, slightly more crowded ventrally, setal formula AA: AB: YZ: ZZ = 2.5: 2: 3: 4 at XIII. Clitellum annular XIV – XVI, setae not visible externally. First dorsal pores 12 / 13. One pair large spermathecal pore in 7 / 8 at 7 th setal line, overhanging lip from VII slightly lateral to pore, distance between spermathecal pores around 1.6–1.8 mm, 0.11–0.15 circumference apart. Female pore single in XIV, 0.3–0.4 mm openings of copulatory bursae paired in XVIII at 5 th setal line, ventral, distance between 1.4–1.5 mm, 0.11–0.13 circumference apart. Genital markings lacking.

Septa 5 / 6, 6 / 7, 7 / 8 muscular but not thick, 8 / 9, 9 / 10 absent, 10 / 11–12 / 13 moderately thick. Gizzard in VIII – X. Esophagus with chevron lamellae XI – XIII; intestine begins in XVI; small, paired lymph glands from XXVII along dorsal vessel; intestinal caeca simple originating in XXVII, and extending anteriorly about to XXIV, tapered sac with some pockets on ventral margins; typhlosole very small found from XXVII, 30 intestinal blood vessels. Hearts in X – XIII esophageal.

Ovaries and funnels in XIII, spermathecae one pair in VII, with nephridia on ducts; spermatheca with thick lenticular ampulla, weakly muscular duct shorter than ampulla; diverticulum chamber small, egg-shaped, iridescent pearl-colored, stalk slender, one or two kinks close to duct. Male sexual system holandric, testes and funnels in ventrally paired sacs in X – XI. Seminal vesicles two pairs in XI – XII, dorsal lobes apical, elongate with wide heads, prostates in XVII – XX, glands 2–3 lobes wrapped around copulatory bursae, muscular ducts form U-shape concave anteriorly on posterior of copulatory bursae lacking stalked glands; duct enters center of copulatory bursae; copulatory bursae openings surrounded toroid pad divided into four wedges, penis triangular block with apical pore.

Differential diagnosis.

Pheretima sorsogonensis sp. nov. has been distinguished from P. bulusanensis sp. nov. and all other known members of the sangirensis group. The final comparison is with P. blackbirdensis sp. nov., from which it differs in having a smaller body size yet greater number of setae, fewer setae between the male pores, and far fewer intestinal blood vessels. In terms of spermathecae, the P. sorsogonensis sp. nov. has weak muscular ducts much shorter than the ampulla, whereas P. blackbirdensis sp nov. has muscular ducts that are nearly as long as the ampulla.

Etymology.

The species is named for its type locality in Sorsogon Province.