Family Lichidae
Subfamilies: Trochurinae
Genera: Belenopyge (= Lobopyge), Ceratarges, Eifliarges, Ohleum.
Lichidae (lichids) are generally rare trilobites. There are some interesting records from the Belgian Lower Devonian in the old literature which were recently confirmed (Belenopyge in the Pragian) but it is the Eifelian (Middle Devonian) that most species come from.
Ceratarges is a characteristic lichid that occurs in the lower and middle Eifelian in the Ardennes. Complete specimens are currently only known from Ceratarges cognatus in the lower Eifelian of the French Ardennes (Vireux-Molhain) and an undescribed species of Ohleum. According to the old literature, Ceratarges armatus (Goldfuss, 1839) occurs in the Couvin area. Recent collections from the Rochefort area include specimens that are possibly conspecific with those from Gees (Trilobitenfelder) in the Eifel.
List of species
Pragian
- Belenopyge sp. (sensu VAN VIERSEN & PRESCHER, 2009)
Eifelian
- Ceratarges cognatus VAN VIERSEN, 2006
- Ceratarges cf. armatus (GOLDFUSS, 1839)
- Ohleum sp.
- Eifliarges sp.
A reconstruction of the pygidium of Ceratarges cf. armatus.
Adopted from van Viersen (2007).
The holotype of Ceratarges ziregensis, a new species which was (along with Ceratarges koumalii and Ceratarges aries) described by van Viersen & Prescher (2011) from the Middle Devonian in Morocco. Specimen was treated with ammonium chloride prior to photography.