Agoniatitaceae

Agoniatites vanuxemi. Photo from here.

Belongs within: Ammonoidea.

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, Agoniatitina]
    |  i. s.: Agoniatites [incl. Aphyllites] H84
    |           |--A. bicaniliculatus H84
    |           |--A. costulatus Holzapfel 1895 D02
    |           |--A. expansus P68
    |           |--A. fecundus H84
    |           |--A. fidelis H84
    |           |--A. fulguralis N79
    |           |--A. holzapfeli Wedekind 1918 D02
    |           |--A. nevadensis Miller 1938 P68
    |           |--A. obliquus (Whidborne 1889) D02
    |           |--A. tabuloides H84
    |           |--A. tuberculosocosatus H84
    |           |--A. vanuxemi (Hall 1879) D02
    |           `--A. verna H84
    `--Pinacitidae KK02
         |--Foorditinae KK02
         |    |--Pseudofoordites Bogoslovsky 1959 KK02
         |    `--Foordites Wedekind 1918 KK02
         |         `--F. buttsi N79
         `--Pinacitinae KK02
              |--Exopinacites Chlupáč & Turek 1983 KK02
              |    `--E. singularis Chlupáč & Turek 1983 KK02
              `--Pinacites Mojsisovics 1882 KK02
                   |--*P. emaciatus H84
                   |--P. eminens Chlupáč & Turek 1977 KK02
                   `--P. jugleri (Roemer 1843) KK02

*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.

[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.