Cognettia lapponica Nurminen, 1965

Felföldi, Tamás, Dózsa-Farkas, Klára, Nagy, Hajnalka & Hong, Yong, 2020, Three new enchytraeid species (Enchytraeidae, Annelida) from mountain soils of Korea and ten species new for the country, Zootaxa 4896 (1), pp. 1-45 : 28

Cognettia lapponica Nurminen, 1965

( Figure 14 )

Material examined. 14 specimens (one was deposited in the National Institute of Biological Resources , Korea; NIBRIV0000837799, slide No. 2542) .

Small worms (6–10 mm long and 230–380 μm wide at XII in vivo), segments 31–36. Chaetae maximum 3 per bundle, sigmoid without nodulus ( Fig. 14C ). Clitellum saddle-shaped, gland cells pattern irregular dorsally ( Fig. 14B ), glands absent ventrally ( Fig. 14C ). Brain slightly incised posteriorly ( Fig. 14A ). Three pairs of nephridia preclitellarly 6/7–8/9 ( Fig. 14D ). In the literature, the position of preclitellar nephridia was unknown ( Nurminen 1965, Schmelz & Collado 2010), but the number of nephridia in Korean specimens differs from those which were collected from Siberia and Alaska, which have 4 pairs of preclitellar nephridia (6/7–9/10) (observation of K. Dózsa- Farkas, unpublished). Three pairs of dorsal pharyngeal lobes free, all without ventral lobes ( Fig. 14D ), and 2 pairs of secondary ventral lobes in V, VI ( Fig. 14D ). Dorsal blood vessel origin in XIV, blood colourless. Sperm funnels 120–180 μm long in vivo, mostly 2.5–3.5 times longer than wide, collar as wide as funnel body ( Fig. 14F ). Spermatozoa 60–78 μm long, heads 25–30 μm. Male pores in normal position in XII, with well-developed glandular bulbs ( Fig. 14E ). Spermathecae ( Figs 14 G–I) confined to V with long ectal ducts and with small ectal glands. Ducts widen into ampullae. Ampulla followed by duct connecting to spherical ental chamber. Spermathecae not connected to oesophagus. One or two mature eggs at a time.

Distribution and habitat in Korea. Mt. Gyebangsan, Nodong-ri, Yongpyeong-myeon, Pyeongchang-gun, Gangwon-do, Q. mongolica forest, N 37°42’27.92”, E 128°29’02.34”, 848 m asl; Mt. Gyebangsan, Nodong-ri, Yongpyeong-myeon, Pyeongchang-gun, Gangwon-do, soil and litter layers of Q. mongolica forest, N 37°42’24.78”, E 128°29’09.95”, 804 m asl.

Figures

FIGURE 14. Micrographs of Cognettia lapponica Nurminen, 1965. A. Brain. B. Clitellar glands, dorsal view. C. Clitellar glands, ventral view (penial bulbs marked with arrows). D. Pharyngeal glands (primary glands marked with black arrows, secondary glands marked with short white arrows, 1st nephridium at 6/7 marked with long white arrow). E. Penial bulbs. F. Sperm funnels. G–I. Spermathecae (ampullae marked with black arrows, ental chamber marked with white arrows). A–H in vivo, I fixed, stained. Scale bars 50 μm.