Belongs within: Agoniatitina.
The Lower to Middle Devonian Agoniatitaceae were an early group of ammonoid cephalopods. They probably started life in shallow waters, becoming more nektonic as they reached maturity (Klug & Korn 2002). Members of the family Pinacitidae possessed a very narrow to closed umbilicus (Klug & Korn 2002); the umbilicus may remain open in other genera.
Characters (from Murray 1985): Serpenticonic to involute, always substantially convolute except earliest whorls. Umbilicus perforate or imperforate. Sutures with at least ventral, lateral and dorsal lobes; biconvex growth lines.
Agoniatitaceae [Agoniatitida]
|--ParentitidaeHK93
| |--Parentites Bogoslovsky 1961KK02
| `--Kimoceras lentiformeHK93
|--MimagoniatitidaeHK93
| |--PalaeogoniatitesH81a
| `--MimagoniatitesHK93
| |--M. bohemicus Chlupáč & Turek 1983HK93
| |--M. falcistria Chlupáč & Turek 1983HK93
| `--M. zorgensisH79
|--PinacitidaeKK02
| | i. s.: HolzapfelocerasH81a
| | |--*H. convolutum (Holzapfel 1895)D02
| | `--H. croyi House 1978D02
| | Wedekindella brilonensis (Kayser 1872)H81a, D02
| |--FoorditinaeKK02
| | |--Pseudofoordites Bogoslovsky 1959KK02
| | `--Foordites Wedekind 1918KK02
| | |--F. buttsiN79
| | `--F. occultusH81b
| `--PinacitinaeKK02
| |--Exopinacites Chlupáč & Turek 1983KK02
| | `--E. singularis Chlupáč & Turek 1983KK02
| `--Pinacites Mojsisovics 1882KK02
| |--*P. emaciatusH84
| |--P. eminens Chlupáč & Turek 1977KK02
| `--P. jugleri (Roemer 1843)KK02
`--AgoniatitidaeHK93
|--Paraphyllites tabuloides Chlupáč & Turek 1983HK93
|--SellagoniatitesH81a
`--Agoniatites [incl. Aphyllites]H84
|--A. bicaniliculatusH84
|--A. costulatus Holzapfel 1895D02
|--A. expansusP68
|--A. fecundusH84
|--A. fidelisH84
|--A. fulguralisN79
|--A. holzapfeli Wedekind 1918D02
|--A. nevadensis Miller 1938P68
|--A. obliquus (Whidborne 1889)D02
|--A. tabuloidesH84
|--A. tuberculosocosatusH84
|--A. vanuxemi (Hall 1879)D02
`--A. vernaH84
*Type species of generic name indicated
References
[D02] Dzik, J. 2002. Emergence and collapse of the Frasnian conodont and ammonoid communities in the Holy Cross Mountains, Poland. Acta Palaeontologica Polonica 47: 565–650.
[HK93] Hewitt, R. A., J. Kullmann, M. R. House, B. F. Glenister & Wang Y.-G. 1993. Mollusca: Cephalopoda (pre-Jurassic Ammonoidea). In: Benton, M. J. (ed.) The Fossil Record 2 pp. 189–211. Chapman & Hall: London.
[H79] House, M. R. 1979. Devonian in the Eastern Hemisphere. In: Robison, R. A., & C. Teichert (eds) Treatise on Invertebrate Paleontology pt A. Introduction. Fossilisation (Taphonomy), Biogeography and Biostratigraphy pp. A183–A217. The Geological Society of America, Inc.: Boulder (Colorado), and The University of Kansas: Lawrence (Kansas).
[H81a] House, M. R. 1981a. On the origin, classification and evolution of the early Ammonoidea. In: House, M. R., & J. R. Senior (eds) The Ammonoidea: The evolution, classification, mode of life and geological usefulness of a major fossil group pp. 3–36. Academic Press.
[H81b] House, M. R. 1981b. Early ammonoids in space and time. In: House, M. R., & J. R. Senior (eds) The Ammonoidea: The evolution, classification, mode of life and geological usefulness of a major fossil group pp. 359–367. Academic Press.
[H84] Hyatt, A. 1883–1884. Genera of fossil cephalopods. Boston Soc. Nat. History, Proc. 22: 253–338.
[KK02] Klug, C., & D. Korn. 2002. Occluded umbilicus in the Pinacitinae (Devonian) and its palaeoecological implications. Palaeontology 45 (5): 917–931.
Murray, J. W. (ed.) 1985. Atlas of Invertebrate Macrofossils. Longman: Harlow.
[N79] Norris, A. W. 1979. Devonian in the Western Hemisphere. In: Robison, R. A., & C. Teichert (eds) Treatise on Invertebrate Paleontology pt A. Introduction. Fossilisation (Taphonomy), Biogeography and Biostratigraphy pp. A218–A253. The Geological Society of America, Inc.: Boulder (Colorado), and The University of Kansas: Lawrence (Kansas).
[P68] Purnell, L. R. 1968. Catalog of the type specimens of invertebrate fossils. Part I: Paleozoic Cephalopoda. United States National Museum Bulletin 262: 1–198.