• Animal Systematics, Evolution and Diversity
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• 제36권3호
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• pp.251-257
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• 2020

The genus Plectus Bastian, 1865 represents a group of free-living freshwater nematodes belonging to the family Plectidae Örley, 1880. However, only one species has been reported thus far from Korea. Plectus aquatilis Andrássy, 1985 and Plectus cirratus Bastian, 1865 are reported for the first time from Korea, from sediments collected from the Nakdong River. Plectus aquatilis is distinguished from other Plectus species by its three longitudinal alae in the lateral field, thin and directed cephalic setae, continuous lip region (head not set-off), and rectangular shaped tail. Plectus cirratus is distinguished from other Plectus species by its large body, two longitudinal alae in the lateral field, larger stoma, and longer tail. Morphological characters and measurements of the specimens generally agree with the original descriptions of Plectus species. Here, the morphological characters (detailed morphometrics) of two species in the genus Plectus are fully redescribed and illustrated using optical microscopy. DNA barcode sequence information from the 18S rDNA gene is also provided for molecular species identification and compared with sequences from other Plectus species available on GenBank.

• Journal of Species Research
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• 제5권3호
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• pp.318-323
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• 2016

Acrobeles ciliatus (von Linstow, 1877) and Plectus parietinus (Bastian, 1865) are newly collected from Korea. Acrobeles is similar to those nematode belongs to Rhabditidae and Panagrolaimidae by having terminal bulb without medium bulb but different by having complex, vines shaped labial attachment. A. ciliatus differed from other Acrobeles species by lateral fields with two incisures, primary axils U-shaped, and secondary axils V-shaped. Head region set off with the neck, three high labial probolae present, each having 5 tines at inner margins and 5-7 at outer margins, and two elongate apical tines. Also, it differs from the longer female body. Plectus parietinus is distinguished from all other species of Plectus by the prominent hypodermal glands, the relatively small amphid, the distinct and well set-off lips and by the subdorsal distal caudal seta on the left side of the tail. Stoma without stylet. Oesophagus about 1/4 of total body length with terminal bulb. Anus ca. $100{\mu}m$ from posterior extremity. Vulva is at middle of body. Have spinneret on tail tip.

• 식물병연구
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• 제22권4호
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• pp.243-248
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• 2016

As preventive measures for bonsai exports, nematodes were isolated from 55 bonsai samples of five coniferous species (Chamaecyparis pisifera, Juniperus chinensis, Pinus densiflora, Pinus thunbergii, and Taxus cuspidate) from all 15 bonsai gardens in Korea. Nematodes belonging to 21 genera in 7 orders were isolated from the 55 bonsai samples. Among plant-parasitic nematodes, Tylenchus spp. was the most frequently isolated (14.9%), followed by Ditylenchus spp. (10.5%), Aphelenchoides spp. (9.5%), Aphelenchus sp. (5.5%), Criconemoides sp. (4.0%), Helicotylenchus sp. (0.7%), Hemicycliophora sp. (0.7%), Mesocriconema sp. (0.7%), Tylenchorhynchus sp. (0.7%), and Paratylenchus sp. (0.4%). Among nonparasitic nematodes, Cephalobina was the most frequently isolated nematodes (26.5%), followed by Rhabditida (19.3%), Dorylaimida (17.8%), Pangrolaimida (14.5%), Plectida (6.5%), Tryphylida (6.2%), Mononchida (3.3%), Alaimida (2.9%), Monhysterida (2.5%), and Triplonchida (0.4%). Based on these results, we conclude that there is no problematic plant-parasitic nematode in bonsai gardens of Korea.