Trefusia De Man 1893
Creators: name: Leduc, Daniel
Publisher: name: Zenodo
Year: 2013
Subjects: Biodiversity
Taxonomy
Animalia
Nematoda
Adenophorea
Enoplida
Trefusiidae
Trefusia

description: Key to the males of Trefusia (modified from Keppner 1992):
1 Large complex sensillae present on ventral surface in cervical region …………………………2
- Large complex sensillae absent on ventral surface in cervical region; small papilliform sensillae may be present in cervical region …………………………………………………………………3
2 Complex cervical sensillae pyriform; spicules narrow, arcuate; tail 7.4 abd long ………………… …………………………………………………………………………… T. honessi Keppner, 1986
- Complex cervical sensillae circular; spicules broad with bladder-like structure on ventral side; tail 15- 17 abd long ……………………………………………………………… T. americana Keppner, 1992
3 Circle of four cephalic sensillae distinctly anterior to amphid …………………………………4
- Circle of four cephalic sensillae in region of, or posterior to amphid ………………………………8
4 Spicules 6.8-7.4 abd long; gubernaculum present ……………………… T. filicauda Allgén, 1933
- Spicules less than 2.5 cbd; gubernaculum present or absent ……………………………………5
5 Amphid situated ≥ 3 cbd from anterior extremity ………………………… T. attenuata Bussau, 1993
- Amphid situated <3 cbd from anterior extremity …………………………………………………6
6 Amphid aperture circular ……………………………………………… T. dominatrix Bussau, 1993
- Amphid aperture oval ………………………………………………………………………………7
7 Amphid aperture transversely oval; tail 4.0 abd long ………………… T. cornea Gerlach, 1958
- Amphid aperture longitudinally oval; tail 20 abd long …………… T. axonolaimoides Allgén, 1953
8 Tail short, conical, 1.0 abd long ……………………………………………… T. conica Gerlach, 1957
- Tail long, conical to filiform, greater than 5.0 abd long ……………………………………………9
9 Gubernaculum present ……………………………………………………………………………10
- Gubernaculum absent ………………………………………………………………………………14
10 Gubernaculum with lateral accessory piece ………………………………………………………11
- Gubernaculum without lateral accessory piece …………………… T. spatulata Keppner, 1992
11 Circle of four sub-cephalic sensillae posterior to amphid; spicules with strong arc ……………
………………………………………………………………………… T. zostericola Allgén, 1933 - Circle of four sub-cephalic sensillae at level of amphid; spicules without strong arc …………12
12 Lateral piece of gubernaculum distinct; spicules without distinct outer median rib (lamella) ……13
- Lateral piece of gubernaculum not distinct; spicules with distinct, outer, median rib; cervical region with single setiform postamphidial sensilla …………… T. longicauda De Man, 1893
13 Cervical region with two or three setae posterior to each amphid; male with longitudinal row of 13 papillae in cervical region; no clusters of dark granules at base of cephalic setae …………………………………………………………………… T. helgolandica Riemann, 1966
- Cervical region with one seta posterior to each amphid; male with longitudinal row of six papillae on wide base in cervical region; clusters of dark granules at base of cephalic setae present ………………………………………………………………………… T. piperata sp. nov.
14 Cervical and pre-cloacal papilliform supplements present on ventral surface; c greater than 5.1 ……………………………………………………………………………………………………15
- Cervical and pre-cloacal papilliform sensillae absent from ventral surface; c = 2.8 ……………… …………………………………………………………………… T. pseudolittoralis Vitiello, 1970
15 Spicules slender, gently curved, capitulum not broad and elongate …………………………16
- Spicules broad, acutely curved, capitulum broad and elongate ………………………………17
16 Pre-cloacal papilliform sensillae 12-18 in number; a = 112-129 ……………………………………
……………………………………………………………… T. multipapillatum Bouwman, 1981 - Pre-cloacal papilliform sensillae 5-7 in number; a = 70-87 ……………… T. littoralis Allgén, 1932
17 Capitulum of spicules with elongate ventral projection … T. curvispiculosa Vincx & Vanreusel, 1989
- Capitulum of spicules without elongate ventral projection ……………………………………18
18 Circle of four sub-cephalic setae posterior to amphid; excretory pore heavily cuticularised; a = 88-117 ……………………………………………………………………… T. longicorpa Keppner, 1986
- Circle of four sub-cephalic setae at level of amphid; excretory pore not observed; a = 53-57 …… ……………………………………………………………………………… T. schiemeri Ott, 1977
description: Published as part of Leduc, Daniel, 2013, Two new free-living nematode species (Trefusiina: Trefusiidae) from the Chatham Rise crest, Southwest Pacific Ocean, pp. 1-13 in European Journal of Taxonomy 55 on pages 7-8, DOI: 10.5852/ejt.2013.55, http://zenodo.org/record/3822945