— 708 — 
Materials and methods : Specimens were borrowed from various Institutions. The follow- 
ing abbreviations hâve been used : BM, British Muséum (Natural History) ; CIH, Commonwealth 
Institute of Helminthology ; ZMB, Zoologischen Muséums Berlin ; MNHN, Muséum national 
d’Histoire naturelle ; USNM, United States National Muséum. 
RESULTS 
The first publication of the name Oxysomatium was in a footnote in a paper by Rail- 
liet & Henry which was presented at a conférence in 1913 but not published until 1914. 
In the published text Oxysomatium lepturum was briefly mentioned as a species possessing 
a preanal sucker. This cannot be considered a valid proposai of the generic name Oxyso¬ 
matium. The name Oxysomatium was not formally proposed as a replacement name for 
Oxysoma Schneider, 1866 (preoccupied), until Railliet & Henry (1916a) clearly stated 
that Oxysomatium brevicaudatum (Zeder, 1800) [= Fusaria brevicaudala Zederj was the 
type species of Oxysomatium Railliet & Henry, 1913. It is likely from the introduction 
to this 1916a article that Railliet & Henry knew as early as 1913 that Oxysoma was 
preoccupied and they decided then on Oxysomatium as a replacement name. This explains 
the apparently anomalous reference to the name Oxysomatium in their 1914 paper. The 
correct author and date citation should be Oxysomatium Railliet & Henry, 1916. 
The genus Neoxysomatium Ballesteros-Mârquez, 1945, was established with Fusaria 
brevicaudala [= Oxysomatium brevicaudalum (Zeder, 1800) Railliet & Henry, 1916] as 
type species. Ballesteros-Mârquez believed at that time that Oxysomatium longes- 
piculum Railliet & Henry, 1916, and Fusaria brevicaudala Zeder were separate species. 
As shown below this is incorrect and Neoxysomatium is a synonym of Oxysomatium. 
Emended Diagnosis of Oxysomatium 
Oxysoma Schneider, 1866 (preoccupied). 
Neoxysomatium Ballesteros-Mârquez, 1945. 
Cosmocercinae sensu Chabaud, 1978, Cosmocercidae, Cosmocercoidea, Ascaridida. Tail 
of male lacking rosettes or plectanes. Somatic papillae and latéral alae présent. Uteri with numer- 
ous thin-shelled, relatively small eggs. Ovary of anterior utérus located just posterior to vulva, 
ovary of posterior utérus located well anterior to vulva. 
Type-species : Oxysomatium brevicaudalum (Zeder, 1800) Railliet & Henry, 1916. 
Oxysomatium most closely resembles Apleclana. These généra may be dilferentiated 
by the location of the two ovaries. In Apleclana both are anterior to the vulva, whereas 
in Oxysomatium the ovary connected to the anterior utérus is posterior to the vulva. For 
this character Aplectana has been described as “ prodelphic ” and Oxysomatium as “ amphi- 
delphic ” (see Chabaud, 1978). This terminology is not followed herein because of ambi- 
guity in the définition of the terms. For example, in the original définition proposed 
by Seurat (1920), one of the examples given of an amphidelphic species, namelv Haemon- 
chus (Trichostrongyloidea), is in its arrangement of uteri and ovaries similar to Aplectana. 
Source : MNHN, Paris 
