摘要：A new heteromorph ammonite genus, Tarrantites, is proposed for Hamites adkinsi Scott, 1928. The description of the new genus is based mainly on a near-complete specimen from the Middle Albian part of the Goodland Limestone of Tarrant County, Texas, the holotype, and on an abraded mould on a pebble from the bed of a stream in Hill County, Texas. In addition, we record the presence of the genus in the Albian of Pakistan. Tarrantites shows a remarkable resemblance to the labeceratine genera Labeceras Spath, 1925 and Myloceras Spath, 1925: in coiling and size to the former, and in ornamentation to the latter, but is excluded from the subfamily Labeceratinae Spath, 1925, because it has a distinct bifid adventive (A) lobe. This latter feature, and the ornamentation, rather suggest affinities of Tarrantites with the family Anisoceratidae Hyatt, 1900.
其他摘要：A new heteromorph ammonite genus, Tarrantites, is proposed for Hamites adkinsi Scott, 1928. The description of the new genus is based mainly on a near-complete specimen from the Middle Albian part of the Goodland Limestone of Tarrant County, Texas, the holotype, and on an abraded mould on a pebble from the bed of a stream in Hill County, Texas. In addition, we record the presence of the genus in the Albian of Pakistan. Tarrantites shows a remarkable resemblance to the labeceratine genera Labeceras Spath, 1925 and Myloceras Spath, 1925: in coiling and size to the former, and in ornamentation to the latter, but is excluded from the subfamily Labeceratinae Spath, 1925, because it has a distinct bifid adventive (A) lobe. This latter feature, and the ornamentation, rather suggest affinities of Tarrantites with the family Anisoceratidae Hyatt, 1900.
