Fridericia seoraksani, Christensen & Dózsa-Farkas, 2012

Christensen, Bent & Dózsa-Farkas, Klára, 2012, A new genus Globulidrilus and three new enchytraeid species (Oligochaeta: Enchytraeidae) from Seoraksan National Park (Korea), Journal of Natural History 46 (45 - 46), pp. 2769-2785 : 2777-2780

publication ID	https://doi.org/ 10.1080/00222933.2012.737038
persistent identifier	https://treatment.plazi.org/id/03E16D7C-FFB0-FFD3-7541-F70F8CE2FCD3
treatment provided by	Felipe
scientific name	Fridericia seoraksani
status	sp. nov.

Treatment

Fridericia seoraksani sp. nov.

( Figures 5 View Figure 5 and 6 View Figure 6 )

Type material

Type Locality. Moderately moist soil at the collecting site.

Holotype. F.16. slide No. 561

Paratypes. P. 92.1–6 slides No. 528, 529, 558, 569, 570, 571. All worms are adult. Deposited in the collection of K. Dózsa-Farkas at Department of Systematic Zoology and Ecology , Eötvös Loránd University , Budapest .

Etymology. Named after the locality where it was found.

Description

Holotype 12.3 mm long, 380 µm wide at VIII and 380 µm at the clitellum (fixed), segments 44. Body length of paratypes 7.2–14.4 mm, width 290–480 µm at VIII and 330–570 µm at the clitellum (in vivo), length of fixed specimens 7.3–11.5 mm, width 290–420 µm at VIII, 350–450 µm at the clitellum, segments 37–45. Chaetae: 4–4,(3),2:4,(5)–4(5),3,2. As in other Fridericia species the chaetae within a bundle are arranged in pairs with the outer being longer and thicker than the inner (52 × 5 µm against 33 × 3 µm in ventro-lateral bundles and 40 × 5 against 30 × 3 µm in dorso-lateral bundles), only two chaetae per bundle in posterior segments. Head pore at 0/I. Dorsal pores from VII. Epidermal gland cells arranged in 2–3 transverse rows per segment, usually with light-brown pigments but occasionally hyaline ( Figure 6C View Figure 6 ).

Clitellum in XII–1/3XIII, girdle-shaped, hyalocytes and granulocytes arranged in dense rows dorsally, hyalocytes also between the penial bulb ( Figure 6A View Figure 6 ), but sometimes only granulocytes ( Figure 6B View Figure 6 ). Thickness of body wall 25–37 µm, cuticle 1.0–1.5 µm (fixed specimens). Brain egg-shaped, 137–150 µm long (fixed), 1.5–2.0 times longer than wide.

Oesophageal appendages (peptonephridia) ( Figure 5A View Figure 5 ) short with a number of short protrusions along their length. Pharyngeal glands mostly free dorsally, but occasionally a narrow connection is seen in the first and second pair, ventral lobes absent in the first pair but present in the second and third ( Figure 5B View Figure 5 ). Chloragocytes from V, dark brown (in vivo). Dorsal vessel from XVI–XVII, blood colourless. Inflated ventral gut epithelium not seen.

Five pairs of preclitellar nephridia from 6/7 to 10/11. Coelomocytes mucocytes (length 20–27 µm) with slightly wavy outline, fine granular matrix and clearly visible nucleus, lenticytes numerous 3–6 µm long. Chylus cells between XII–XV occupying two segments. Seminal vesicle absent. Sperm funnels cylindrical ( Figure 5C View Figure 5 , 6D View Figure 6 ), small, 160–190 µm long and 60–75 µm wide (in vivo) 2.0–2.5 times as long as wide. In fixed specimens the length of funnels are 100–150 µm. Collar slightly narrower than funnel. Spermatozoa long: 290–380 µm long, heads 110–130 µm (in vivo), 115–325 µm long and the head 75 µm (fixed). Diameter of sperm ducts 5 µm (fixed). Male copulatory organs ( Figure 6B View Figure 6 ) are 75–110 µm long, 75–100 µm wide and 80–100 µm high (fixed), the laterally bent bursal slits are longitudinal ( Figure 6A View Figure 6 ). No subneural glands. Ectal ducts of spermathecae relatively long, length 225–360 µm and width 15–17.5 µm in vivo (160–300 µm resp. 13–17 µm when fixed). Ampullae onion-shaped without diverticula, 50–60 µm wide (fixed), ental bulbs projecting into the lumina, sperm in circles around the bulb. The proximal part of the ampulla short (about 50µm, fixed), separate openings into oesophagus; gland absent at the ectal opening ( Figures 5D View Figure 5 and 6E–F View Figure 6 ); one to four mature eggs at a time.

Distribution and habitat

Only known from the type locality.

Differential diagnosis

Among the previously described Fridericia species with about 40 segments, four (five) chaetae per bundle in anterior segments, onion-shaped spermathecal ampulla without diverticula and separate openings into oesophagus, three species ( F. paratalassia Schmelz, 2002 , F. fuchsi Eisen, 1904 , F. tuberosa Rota, 1995 ) are similar to the new species. The main differences are as follows: in F. paratalassia , the ampullae of spermathecae are larger in diameter [70–100 µm ( Schmelz 2003), 100–200 µm ( Nielsen and Christensen 1959)]; F. fuchsi is slightly larger (40–45 segments and 10–15 mm long) and the spermathecal ampullae are also much wider: diameter 76–110 µm ( Eisen 1904, Dózsa-Farkas and Christensen 2002), but these are only 42.0–62.5 µm in F. seoraksani , and the spermathecal ducts are much longer. In F. tuberosa diverticula-like protrusions may appear on the spermathecal ampullae, they have spermathecal ectal glands and subneural glands; moreover the coelomocytes are b-type. The spermatheca of F. peregrinabunda Michaelsen, 1913 (the species which occurs also in Korea) is very similar to the spermatheca of the new species, but the differences are clear-cut (e.g. F. peregrinabunda has only two chaetae in bundles).