Monodechenella grandis

Vanderlaan, Tegan A. & Ebach, Malte C., 2015, A review of the Carboniferous and Permian trilobites of Australia, Zootaxa 3926 (1), pp. 1-56 : 22

Monodechenella grandis (Etheridge Jr 1892a)

1892a Phillipsia grandis Etheridge Jr. ; p. 128, text-fig. 5.

1892a Griffithides sweeti Etheridge Jr. ; p. 125.

1892b Phillipsia woodwardi Jack and Etheridge Jr. ; p. 215, pl. 7, fig. 13. 1892b Phillipsia dubia Jack and Etheridge Jr. ; p. 214, pl. 8, fig. 6. 1892b Phillipsia ? sp. indet. ( grandis ); Jack and Etheridge Jr., p. 215. 1894 Griffithides sweeti ; Etheridge Jr., p. 528, pl. 39, fig. 3.

1918 Phillipsia ? robusta; Mitchell, p. 441, 451, pl. 47, figs. 1–8. 1918 Phillipsia grandis ; Mitchell, p. 463, pl. 47, fig. 2, pl. 50, figs. 1–3. 1918 Phillipsia woodwardi ; Mitchell, p. 465, pl. 49, figs. 1, 5–8. 1918 Griffithides sweeti ; Mitchell, p. 479, pl. 53, figs. 1–2.

1963 Phillipsia ? grandis ; Campbell & Engel, p. 113, pl. 7, figs. 34–35. 1969 Cyrtoproetus sweeti ; Hahn & Hahn, p. 371.

1970 Linguaphillipsia grandis ; Osmólska, p. 48, tab. 1.

1972 Linguaphillipsia ? grandis ; Hahn & Hahn, p. 371.

1972 Conophillipsia woodwardi ; Hahn & Hahn, p. 387.

1984 Conophillipsia grandis ; Engel & Morris, p. 53–58, figs. 18, 19.

Lectotype. AMF35853 (internal mould of pygidium).

Locality. Type—location unknown.

Emended diagnosis. Glabella strongly convex, overhanging the anterior border furrow; glabellar width greater than length. Ten thoracic segments. Pygidium semi-elliptical and convex; axis of equal height anteriorly to posteriorly; axial ring furrows undulating; 11–12 pleural ribs; border convex.

Remarks. Monodechenella grandis (Etheridge Jr. 1892a) closely resembles M. subquadrata in that they both have narrow, convex pygidial borders, a sub-cylindrical outline and a densely nodose glabella. They can be differentiated by the distinct shape of the cephalon of M. grandis , distinct S2 and S3 on M. subquadrata , and the curving ribs of M. subquadrata . The diagnosis by Engel & Morris (1984) has been emended to include thoracic segment numbers, and to remove the shape of the genal angles, as preservation of the specimens do not allow this characteristic to be seen clearly.