Tylenchorhynchus

The plant-parasitic nematode genus Tylenchorhynchus Cobb, 1913 includes at present more then 130 nominal species (sensu Geraert, 2011). While identification towards species level is difficult, as a genus it is easy to recognize. The body is about 1 mm or less in length, cleary annulated, with a lateral field with four incisures.

The cephalic region can be offset from body or continuous and annulated or smooth. The stylet is well developed and 15 to 25 micrometer in length, stylet knobs are prominent. The median bulb is rounded to oval in shape, the basal bulb is offset from the intestine, rarely a small overlap is present. The vulva can be found at mid-body, with paired outstreched ovaries. Female tail conoid to cylindroid in shape with a blunt smooth or annulated tail tip. Males are usually present in most species. This genus occurs world-wide and feeds ecto-parasitic on many plant species.

Tylenchorhynchus dubius

Tylenchorhynchus dubius: female body
Tylenchorhynchus dubius: female body

Tylenchorhynchus dubius: offset cephalic region, stylet and median bulb.
Tylenchorhynchus dubius: offset cephalic region, stylet and median bulb.

Tylenchorhynchus dubius: oval shaped median
Tylenchorhynchus dubius: oval shaped median
Tylenchorhynchus dubius: median bulb and basal bulb, S-E duct visible
Tylenchorhynchus dubius: median bulb and basal bulb, S-E duct visible
Tylenchorhynchus dubius: vulva at mid-body with irregular annulation close to vulva
Tylenchorhynchus dubius: vulva at mid-body with irregular annulation close to vulva
Tylenchorhynchus dubius: vulva at mid-body with irregular annulation near vulva
Tylenchorhynchus dubius: vulva at mid-body with irregular annulation near vulva
Tylenchorhynchus dubius: tail with anus and smooth rounded tail tip
Tylenchorhynchus dubius: tail with anus and smooth rounded tail tip
Tylenchorchynchus dubius: tail tip with small hyaline tail part
Tylenchorchynchus dubius: tail tip with small hyaline tail part

(Click on the pictures for an enlargement, ©Wageningen University & Research, Laboratory of Nematology/Pictures: Hanny van Megen)