Hemifridericia parva Nielsen and Christensen, 1959

Torii, Takaaki, Akagi, Tomohiro, Uchino, Toru & Kobayashi, Tohru, 2018, New descriptions of enchytraeid species (Clitellata: Enchytraeidae) from Korea, Journal of Species Research 7 (1), pp. 80-91 : 86-87

4. Hemifridericia parva Nielsen and Christensen, 1959

( Fig. 6 )

Hemifridericia parva Nielsen and Christensen, 1959: 68 , Figs. 68-70; Dózsa-Farkas & Hong, 2010: 31, Table 1. Dózsa-Farkas & Felföldi, 2015: 185-192, Table 1, Fig.

1A, C, E, G, H, Fig. 2C, D, G , Fig. 3 B-D, F, Fig. 4A . New Korean name: Aegi-ae-jireongi (OinjOiNjffiḍ)

Material examined. Korea, Jeollabuk-do, Namwongun, Unbong-myeon, Mt. Jiri , Bamsagol Valley , litter layers in deciduous forest (35°46′05.7″N, 126°43′14.7″ E), 18 September 2008 and 6 October 2008, Y. Hong coll.

Diagnosis. 2-3 mm long and 150-200 μm wide worms in vivo with 15-21 segments. Chaetae straight without nodulus, proximally bent, gradually increasing in size from anterior to caudal segments, formula: 2-2: 2,3,(1)-2. Three pairs of pharyngeal glands, all with ventral lobes, two anterior pairs with dorsal connection or separat- ed, posterior pair in VI elongate, never united dorsally. Brain deeply incised posteriorly ( Fig. 6A ). In ventral bundles, preclitellarly 3 chaetae except in II and XI (with two chaetae) ( Fig. 6D ). Two chaetae present in XII in lateral bundles, also ventrally near penial bulbs ( Fig. 6C ), a rare character in enchytraeids. Clitellum over XII-1/2 XIII, saddle-shaped, large square hyalocytes and granulocytes in transverse rows dorsally. No oesophageal appendages. Coelomo-mucocytes scarce, oval with weakly granular texture, length of 13-20 μm, lenticytes very numerous, 5-10 μm long (in vivo). Chloragogen cells forming a prominent layer of large cells about 20- 37 μm in diameter with refractile globules. Three pairs of nephridia ( Fig. 6B ) in preclitellar region at 6/7, 7/8, and 9/10. Dorsal blood vessel originating in XII, blood colorless, anterior bifurcation of dorsal blood vessel in I. Seminal vesicle absent. Sperm funnel ( Fig. 6E ) small, pear-shaped, about 40 μm long, collar slightly narrower than funnel body. Spermatozoa about 45-50 μm long, heads about 18-20 μm long (in vivo). Male copulatory organs small and compact, 47-56 μm long. Spermathecae ( Fig. 6F ) with long ectal ducts devoid of glands, ampullae spherical, 15-20 μm in diameter in vivo, ental ducts fused, one common opening into oesophagus. One or two mature eggs present at a time (Dózsa-Farkas and Felföldi, 2015).

Remarks. Genus Hemifridericia Nielsen and Christensen, 1959 is currently composed of two valid species. Habitat and distribution. Wet soils and widespread ( Schmelz and Collado, 2010).

Deposition. NIBRIV0000544613.

Figures

Fig. 6. Micrographs of Hemifridericia parva. A. Brain; B. Nephridium preclitellarly; C. Clitellar area ventral view (clitellar chaetae marked with black arrows, sperm funnel marked with white arrow); D. Ventral chaetae from II (only 2 chaetae), III-V segments (3 chaetae in a bundle) ventral view; E. Sperm funnels (marked with arrows); F. Spermathecae (only one of the pair is visible). All micrograph in vivo. Scale bars: 50μm.

Fig. 1. Micrographs of Enchytraeus buchholzi. A. Clitellar glands lateral view (male copulations organ marked with arrow); B. Clitellar glands ventral view (male copulations organ marked with arrows); C. Oesophageal appendage (marked with arrow); D. Coelomocytes; E. Sperm funnel (marked with arrow, e. submature oocytes); F, G. Sperm funnels (marked with arrows); H. Everted bursa lateral view (marked with arrow); I. Spermatheca lateral view (marked with arrow).All micrograph in vivo. Scale bars: 50μm.

Fig. 2. Micrographs of Enchytraeus irregularis. A. Many small epidermal glands in segment III, ventral view; B. Clitellar glands dorsal view; C. Head pore lateral view (marked with arrow) and the anterior dorsal blood vessel (the blood is faintly red); D. Brain (the four aggregation of refractile globules marked with arrows); E. Brain of a fixed and stained specimen; F. Coelomocytes; G. Coelomocytes in 100× magnification; H. Chloragogen cells; I. Pharyngeal glands (p), spermathecal diverticula marked with arrows; J. Sperm funnels. All micrographs in vivo except E and I. Scale bars: 50μm except G (20 μm).

Fig. 3. Micrographs of Enchytraeus irregularis. A. Everted bursa of male copulations organ (marked with white arrow) vas deferens and extra copulations gland (marked with black arrow) lateral view; B. Male copulations organ with a glandular bulb and more glandular bodies; C. Bursal slit; D, E. Male copulations organs of fixed and stained specimens lateral and ventral views; F. Clitellum ventral view (male copulations organ marked with white arrows) and extra copulations glands (marked with black arrows); G.Accessory sexual gland exceptionally in segment XV; H, I. Accessory sexual glands in XIII ventral view, and lateral view respectively. A-C, F, H, I, in vivo; D, E, G, fixed and stained. Scale bars: 50μm.

Fig. 4. Micrographs of Enchytraeus irregularis. A, B. Spermathecae (spermathecal diverticula marked with black arrows, ectal glands marked with white arrows, (a), ampullae.A, in vivo; B, fixed and stained. Scale bars: 50μm.