Belongs within: Neograptina.
Contains: Monograptus, Saetograptus, Cucullograptus, Cyrtograptus.
The Monograptina are a group of graptolites known from the Lower Silurian to the Lower Devonian, characterised by the production of a uniserial rhabdosome with thecae along one side only of the central stipe (Bulman 1970).
The Cyrtograptinae are a group of uniserial graptolites known from the Middle Silurian, characterised by the regular production of thecal cladia (Bulman 1970).
Rastrites: stringing out thecae
Published 5 April 2011
The latter part of the Ordovician saw a turnover in the graptoloids, the planktonic branch of the early Palaeozoic colonial graptolites. The basally-branched forms that had been among the earliest graptoloids became extinct, leaving only the scandent forms surviving in the Silurian. Scandent colonies grew as a single linear stipe, which might have thecae (the openings for individual members of the colony) in two lines, one on either side of the stipe, or in a single line on one side of the stipe. The latter form characterised the Monograptidae, which were to become the latest surviving graptoloids (Bulman 1970).
Despite their long survival, monograptids were mostly a fairly uniform bunch. Their simple morphology did not give much scope for obvious morphological variation, and many monograptid lineages were not greatly distinct in colony form. One of the more distinct forms was the short-lived genus Rastrites which occurred during the Llandovery period of the early Silurian (and so relatively early in the history of the monograptids). Species of Rastrites developed very long and slender, widely spaced thecae that stode out perpendicular from the connecting stipe like the strings on an Incan quipu.
Rickards et al. (1977) suggested that the genus Rastrites is polyphyletic, deriving separate lineages within the genus from a number of different (albeit closely related) species assigned to the separate genus Monograptus. To a certain extent, the distinction is a little arbitrary: these ancestral Monograptus (treated by some authors as a third genus, ‘Demirastrites‘) also had elongate thecae, but not yet to the same degree as developed by Rastrites proper, and not as widely spaced. But that, after all, is the nature of evolution, and the limitation of any classificatory system. You have to draw a line somewhere.
Systematics of Monograptoidea
Monograptoidea [Akidograptinae, Dimorphograptidae, Heteroprionidae, Mono-Amphiphyontes]M14
| i. s.: Cardograptus Hundt 1965 (n. d.)M14
| Metadimorphograptus Přibyl 1948M14
| `--*M. extenuatus (Elles & Wood 1908) [=Dimorphograptus extenuatus, Rhaphidograptus extenuatus]B70
| Parakidograptus Li & Ge 1981M14
| `--P. acuminatusP98
|--Avitograptus Melchin et al. 2011M14
| `--A. avitusM14
`--+--Akidograptus Davies 1929 M14, B70
| |--*A. ascensus Davies 1929B70
| `--A. acuminatus (Nicholson 1867)R93 [=Cephalograptus acuminatusB70]
`--+--Dimorphograptus Lapworth 1876M14, B70 [incl. Bulmanograptus Přibyl 1948B70]
| |--*D. elongatus Lapworth 1876B70
| |--D. confertus Nicholson 1868 [=*Bulmanograptus confertus]B70
| `--D. decussatusB70
`--Monograptidae (see below for synonymy)MCM09
|--Falcatograptus Hundt 1965 (n. d.)BR70
|--Mystiograptus Hundt 1965 (n. d.)BR70
|--Nodosograptus Hundt 1951 (n. d.)BR70 [=NodosugraptusM14]
|--Paragraptus Hundt 1965 (n. d.)BR70
|--MonograptusBR70
|--SaetograptusBR70
|--CucullograptusBR70
|--Pristiograptus Jaekel 1889BR70
| |--*P. frequens Jaekel 1889BR70
| |--P. dubiusZL97
| |--P. fecundusB70
| |--P. jaegeriNL12
| |--P. nudusM79
| |--P. regularisZL97
| |--P. transgrediensB70
| |--P. tumescensZL97
| `--P. ultimusB70
|--‘Acanthograptus’ Tsegelniuk 1976 non Spencer 1878M14
| |--A. aculeatusK83
| `--A. spineusK83
|--Alexandrograptus Přibyl 1981M14
|--CyrtograptusB70
|--Awarograptus Zalasiewicz & Howe 2003M14
|--Bugograptus Tsegelniuk 1976M14
|--Cochlograptus Obut 1987M14
|--Crinitograptus Rickards 1995M14
|--Cultellograptus Loydell & Nestor 2006M14
|--Dibranchiograptus Hundt 1949 (n. d.)M14
|--Didymograptoides Hundt 1951 (n. d.)M14
|--Dulebograptus Tsegelniuk 1976M14
|--Egregiograptus Rickards & Wright 1997M14
|--Enigmagraptus Rickards & Wright 2004M14
|--Euroclimacis Štorch 1998M14
|--Formosograptus Bouček et al. 1976M14
|--Fterograptus Tsegelniuk 1976M14
|--Heisograptus Tsegelniuk 1976M14
|--Hemimonograptus Zhao 1984M14
|--Hubeigraptus Li 1995M14
|--Huttagraptus Koren’ & Bjerreskov 1997M14
|--Istrograptus Tsegelniuk 1976M14
|--Korenea Rickards et al. 1995M14
|--Kurganakograptus Golikov 1969M14
|--Lenzia Rickards & Wright 1999M14
|--Neocolonograptus Urbanek 1997M14
|--Neolagarograptus Štorch 1998M14
|--Paradiversograptus Sennikov 1976M14
|--Paramonoclimacis Wang & Ma in Wang & Jin 1977M14
|--Polonograptus Tsegelniuk 1976M14
|--Prochnygraptus Přibyl & Štorch 1985M14
|--Procyrtograptus Poulsen 1943M14
|--Prolinograptus Rickards & Wright 1997M14
|--Proteograptus Lenz et al. 2012M14
|--Pseudostreptograptus Loydell 1991M14
|--Quasipernerograptus Zhao 1984M14
|--Skalograptus Tsegelniuk 1976M14
|--Slovinograptus Urbanek 1997M14
|--Tamplograptus Tsegelniuk 1976M14
|--Thuringiograptus Hundt 1935M14
|--Tirassograptus Tsegelniuk 1976M14
|--Torquigraptus Loydell 1993M14
|--Trimorphograptus Zhao 1984M14
|--Uncinatograptus Tsegelniuk 1976M14
|--Urbanekia Rickards & Wright 1999M14
|--Vietnamograptus van Phuc 1998M14
|--Wandograptus Rickards & Jell 2002M14
|--Wolynograptus Tsegelniuk 1976M14
|--Pseudomonoclimacis Mikhailova 1975ZL97
| |--P. bandaletoviK83
| |--P. dalejensis (Bouček 1936) [=Monograptus dalejensis; incl. M. haupti Kühne 1955]ZL97
| `--P. minimusK83
|--Linograptus Frech 1897B70
| `--*L. posthumus (Richter 1875) (see below for synonymy)B70
|--Sinodiversograptus Mu & Chen 1962B70
| `--*S. multibrachiatus Mu & Chen 1962B70
|--Averianowograptus Obut 1949M14
| `--*A. magnificus (Averianow 1931) [=Cyrtograptus magnificus]B70
|--Barrandeograptus Bouček 1933B70
| `--*B. pulchellus (Tullberg 1883) [=Cyrtograptus pulchellus]B70
|--Lituigraptus Ni 1978M14
| `--L. convolutusK-D04
|--Stimulograptus Přibyl & Štorch 1983M14
| `--S. sedgwickiK-D04
|--Atavograptus Rickards 1974M14
| |--A. atavusM14
| `--A. ceryx (Rickards & Hutt 1970)R93
|--Abiesgraptus Hundt 1935M14 [incl. Gangliograptus Hundt 1939B70]
| |--*A. multiramosus Hundt 1935B70
| `--‘*Gangliograptus’ hoppeianus Hundt 1939B70
|--Diversograptus Manck 1923B70
| |--*D. ramosus Manck 1923B70
| `--D. runcinatus [=Monograptus runcinatus]BR70
|--Neodiversograptus Urbanek 1963B70
| |--*N. nilssoni (Lapworth 1876) [=Monograptus nilssoni]B70
| |--N. beklemischeviB70
| `--N. kozlowskiiK83
|--Neocucullograptus Urbanek 1970M14
| |--N. inexpectatusJT12
| `--N. kozlowskii Urbanek 1970K83
|--Neolobograptus Urbanek 1970M14
| |--N. ariculatusZL97
| `--N. nilssoniK-D04
|--Pribylograptus Obut & Sobolevskaya 1966M14, BR70
| |--*P. incommodus (Törnquist 1899) [=Monograptus incommodus]BR70
| `--P. argutusM14
|--Spirograptus Gürich 1908M14, BR70 [=Tyrsograptus Obut 1949BR70]
| |--*S. turriculatus (Barrande 1850)BR70, B70 (see below for synonymy)
| |--S. guerichiK-D04
| `--S. tullbergiBR70
|--Streptograptus Yin 1937M14, BR70
| |--*S. nodifer (Törnquist 1881) [=Monograptus nodifer]BR70
| |--S. dalecarlicusM14
| `--S. sartoriusM14 [=Monograptus sartoriusBR70]
|--Monoclimacis Frech 1897BR70
| |--*M. vomerina (Nicholson 1872) [=Graptolithus vomerinus]BR70
| |--M. crenulataB70
| |--M. griestoniensisB70
| `--M. micropomaBR70
|--Rastrites Barrande 1850BR70 (see below for synonymy)
| |--*R. peregrinus Barrande 1850BR70 [=*Rastrograptus peregrinusB70]
| |--R. longispinusB70
| |--R. maximusB70
| |--‘*Stavrites’ rossicus Obut & Sobolevskaya 1968BR70
| `--‘*Corymbites’ sigmoidalis Obut & Sobolevskaya 1967BR70
|--Pernerograptus Přibyl 1941NJ83
| | i. s.: P. neotericus Ni & Jiao 1983NJ83
| | P. supernus Ni & Jiao 1983NJ83
| |--*P. argenteus (Nicholson 1867)BR70 [=Graptolithus argenteusBR70, Monograptus argenteusNJ83, BR70]
| `--+--‘Monograptus’ ramstalensisNJ83
| `--P. urbanus Ni & Jiao 1983NJ83
|--Neomonograptus Mu & Ni 1973M14
| | i. s.: N. shidianensis Ni & Jiao 1983NJ83
| |--N. falcariusNJ83
| |--N. hercynicusNJ83
| `--+--N. fanicusNJ83
| `--+--N. atopusNJ83
| | |--N. a. atopusNJ83
| | `--N. a. rigidusNJ83
| `--N. himalayensisNJ83
|--Metamonograptus Wang 1977NJ83
| | i. s.: M. arcuatus Ni & Jiao 1983NJ83
| | M. craigensis [=Monograptus craigensis]NJ83
| | M. facetus Ni & Jiao 1983NJ83
| | M. giganteus Ni & Jiao 1983NJ83
| |--M. birchensis [=Monograptus birchensis]NJ83
| `--+--M. praehercynicusNJ83
| `--+--M. hemiodonNJ83
| `--+--M. qinzhouensis [=Monograptus qinzhouensis]NJ83
| `--M. telleriNJ83
`--Bohemograptus Příbyl 1967K83, BR70
|--*B. bohemicus (Barrande 1850)B70 (see below for synonymy)
| |--B. b. bohemicusZL97
| |--B. b. garrattiZL97
| `--B. b. tenuis (Bouček 1936) [=Monograptus bohemicus tenuis]ZL97
|--B. butovicensisK83
`--B. praecornutusZL97*Bohemograptus bohemicus (Barrande 1850)B70 [=Graptolithus bohemicusZL97, Monograptus bohemicusZL97, Pristiograptus bohemicusBR70]
*Linograptus posthumus (Richter 1875) [=Dicranograptus posthumus; incl. L. nilssoni Frech 1897 nec Graptolithus nilssoni Barrande 1850 nec Monograptus nilssoni Lapworth 1876]B70
Monograptidae [Cucullograptinae, Cyrtograptidae, Cyrtograptinae, Linograptidae, Linograptinae, Mono-Diprionidae, Monograpta, Monograptina, Monograptinae, Monoprionida, Monoprionidae, Neocucullograptinae, Pristiograptini, Saetograptinae]MCM09
Rastrites Barrande 1850BR70 [=Rastrograptus Hopkinson & Lapworth 1875B70; incl. Corymbites Obut & Sobolevskaya in Obut et al. 1967 non Latreille 1834BR70, M14, Stavrites Obut & Sobolevskaya in Obut et al. 1968BR70, M14]
*Spirograptus turriculatus (Barrande 1850)BR70, B70 [=Graptolithus turriculatusBR70, Monograptus turriculatusB70, *Tyrsograptus turriculatusBR70]
*Type species of generic name indicated
References
[B70] Bulman, O. M. B. 1970. Graptolithina with sections on Enteropneusta and Pterobranchia. In: Teichert, C. (ed.) Treatise on Invertebrate Paleontology pt V 2nd ed. pp. V1–V149. The Geological Society of America, Inc.: Boulder (Colorado), and the University of Kansas: Lawrence (Kansas).
[BR70] Bulman, O. M. B., & R. B. Rickards. 1970. Classification of the graptolite family Monograptidae Lapworth, 1873. In: Teichert, C. (ed.) Treatise on Invertebrate Paleontology pt V 2nd ed. pp. V149–V157. The Geological Society of America, Inc.: Boulder (Colorado), and the University of Kansas: Lawrence (Kansas).
[JT12] Jeppsson, L., J. A. Talent, R. Mawson, A. Andrew, C. Corradini, A. J. Simpson, J. Wigforss-Lange & H. P. Schönlaub. 2012. Late Ludfordian correlations and the Lau Event. In: Talent, J. A. (ed.) Earth and Life: Global biodiversity, extinction intervals and biogeographic perturbations through time pp. 653–675. Springer.
[K83] Koren’, T. N. 1983. New Late Silurian monograptids from Kazakhstan (USSR). Palaeontology 26 (2): 407–434.
[K-D04] Kozłowska-Dawidziuk, A. 2004. Evolution of retiolitid graptolites—a synopsis. Acta Palaeontologica Polonica 49 (4): 505–518.
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[MCM09] Maletz, J., J. Carlucci & C. E. Mitchell. 2009. Graptoloid cladistics, taxonomy and phylogeny. Bulletin of Geosciences 84 (1): 7–19.
[M79] Müller, A. H. 1979. Fossilization (taphonomy). In: Robison, R. A., & C. Teichert (eds) Treatise on Invertebrate Paleontology pt A. Introduction. Fossilisation (Taphonomy), Biogeography and Biostratigraphy pp. A2–A78. The Geological Society of America, Inc.: Boulder (Colorado), and The University of Kansas: Lawrence (Kansas).
[NJ83] Ni Y.-N. & Jiao S.-D. 1983. Lower Devonian graptolites from Yunnan. Acta Palaeontologica Sinica 22 (3): 295–307.
[NL12] Noble, P. J., A. C. Lenz, C. Holmden, M. Masiak, M. K. Zimmerman, S. R. Poulson & A. Kozłowska. 2012. Isotope geochemistry and plankton response to the Ireviken (earliest Wenlock) and Cyrtograptus lundgreni extinction events, Cape Phillips Formation, Arctic Canada. In: Talent, J. A. (ed.) Earth and Life: Global biodiversity, extinction intervals and biogeographic perturbations through time pp. 631–652. Springer.
[P98] Prothero, D. R. 1998. Bringing Fossils to Life: An introduction to paleobiology. WCB McGraw-Hill: Boston.
Rickards, R. B., J. E. Hutt & W. B. N. Berry. 1977. Evolution of the Silurian and Devonian graptoloids. Bulletin of the British Museum (Natural History): Geology series 28 (1): 1–120.
[R93] Rickards, R. B. 1993. Graptolithina. In: Benton, M. J. (ed.) The Fossil Record 2 pp. 537–542. Chapman & Hall: London.
[ZL97] Zhang Y. & A. C. Lenz. 1997. Uppermost Wenlock and Ludlow graptolites from southern Yunnan, China. Canadian Journal of Earth Sciences 34: 1220–1238.