Brachiopods, crustaceans, vertebrates, and charophytes from the Devonian Ly Hoa, Nam Can and Dong Tho formations of Central Vietnam Racheboeuf, Patrick Phuong, Ta Hoa Hung, Nguyen Huu Feist, Monique Janvier, Philippe Geodiversitas 2006 28 1 5 36 Lyaschenko, 1973 Lyaschenko 1973 [814,1149,1229,1256] Strophomenata Chonetidae Corbicularia GBIF Animalia Strophomenida 20 25 Brachiopoda genus    TYPESPECIES. —  Chonetes menneriLyaschenko, 1958. Frasnian, Russian Platform.  DISCUSSION In the literature, four chonetoidean genera, namely  Striatochonetes Mikrjukov, 1968,  RhyssochonetesJohnson, 1970,  CorbiculariaLyaschenko, 1973, and  CeduliaRacheboeuf, 1979, have been defined as including in their diagnosis concentric fila crossing the radial ornament.  Ceduliahas already been considered as a junior synonym of  Rhyssochonetes( Racheboeuf 1981, 2000). The relationships between  Striatochonetes,  Rhyssochonetes, and  Corbiculariahave also been discussed ( Johnson 1978; Racheboeuf 1981), but the question remained unanswered, mainly because the preservation of the original specimens is different. The former of these three genera,  Striatochonetes, was defined with  Strophomena setigeraHall, 1843as the typespecies. However  Strophomena setigeraexhibits no more than three to four concentric growth lines and lacks the typical concentric fila which are included in the original diagnosis, as established by Johnson (1978), and which are well developed in  S. krylovae Mikrjukov, 1968( Mikrjukov 1968: pl. 33, figs 3, 4). The genus name  Striatochoneteshas thus to be restricted to the typespecies  S. setigeraHall, 1843, until the species is carefully revised. The shell of  CorbiculariaLyaschenko, 1973is morphologically very close to that of  RhyssochonetesJohnson, 1970, and Johnson (1978: 125)considered that  Corbiculariawas a probable junior synonym of  Rhyssochonetes. The main difference lies in: 1) a less transverse, more rounded, shell outline in  Corbiculariathan in  Rhyssochonetes; 2) the orientation of the spines, which are at 45° in  Rhyssochonetes, and high-angled to perpendicular in  Corbicularia; and 3) the development of a pair of long but faint accessory septa in  Corbicularia, at least in the species  C. cracoviensisBalinski, 1979. Although the species assigned to  Corbicularia, all from the Givetian and Frasnian of the Russian Platform, are poorly known internally, the two genera,  Rhyssochonetesand  Corbicularia, are here still provisionally regarded as distinct. The species  Striatochonetes?  parisi Racheboeuf, 1981, and S.?  goasquellouensis Racheboeuf, 1981are reassigned to  Corbiculariaaccording to their shell size and outline, and high-angled spines.