Nguyen Thi Anh Duong, PeÑa-Santiago Reyes
Institute of Ecology and Biological Resources, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet, Hanoi, Vietnam. Departamento de Biología Animal, Biología Vegetal y Ecología, Universidad de Jaén, Campus 'Las Lagunillas' s/n, Edificio B3, 23071- Jaén, Spain. Department of Terrestrial Ecology, Zoological Institute, University of Cologne, Zülpicher Straße 47b, D-50674 Cologne, Germany..
Zootaxa. 2018 Apr 27;4415(1):150-160. doi: 10.11646/zootaxa.4415.1.7.
Two new species of the genus Metaxonchium are described from natural habitats of Vietnam. Metaxonchium bonkowskii sp. n. is characterized by its 1.69-2.23 mm long body, lip region offset by weak constriction and 9.5-10.5 µm broad, odontostyle 11-13 µm long, neck 673-868 µm long with the pharyngeal expansion occupying 66-77% of its length, anterior genital branch reduced to a uterine sac 75-135 µm long or 4-7% of body length, posterior uterus tetrapartite and including a Z-like differentiation, V = 51-55, and female tail short and rounded (37-51 µm, c = 66-97, c' = 0.5-0.7). Metaxonchium silvaticum sp. n is characterized by its 1.28-1.43 mm long body, lip region offset by weak depression and 7.0 µm broad, odontostyle 8-9 µm long, neck 502-630 µm long with the pharyngeal expansion occupying 65-76% of its length, anterior genital branch reduced to a uterine sac 65-80 µm long or 4-6% of body length, posterior uterus tripartite, non-echinophor, V = 52-57, tail short and rounded (18-23 µm, c = 56-74, c' = 0.6-0.8) with abundant blister-like or saccate bodies, spicules 41 µm long, and seven spaced ventromedian supplements.
从越南的自然栖息地描述了Metaxonchium属的两个新物种。邦科夫斯基氏新种Metaxonchium bonkowskii sp. n. 的特征为：体长1.69 - 2.23毫米，唇区由微弱缢缩与身体分开，宽9.5 - 10.5微米，口针长11 - 13微米，颈部长673 - 868微米，咽扩张部分占其长度的66 - 77%，前生殖支退化为一个长75 - 135微米或体长4 - 7%的子宫囊，后子宫分为四部分且包括一个Z形分化，V = 51 - 55，雌虫尾短且圆（37 - 51微米，c = 66 - 97，c' = 0.5 - 0.7）。林地新种Metaxonchium silvaticum sp. n. 的特征为：体长1.28 - 1.43毫米，唇区由微弱凹陷与身体分开，宽7.0微米，口针长8 - 9微米，颈部长502 - 630微米，咽扩张部分占其长度的65 - 76%，前生殖支退化为一个长65 - 80微米或体长4 - 6%的子宫囊，后子宫分为三部分，无刺突，V = 52 - 57，尾短且圆（18 - 23微米，c = 56 - 74，c' = 0.6 - 0.8），有大量水泡状或囊状小体，交合刺长41微米，以及七个间隔的腹中线副附器。
