Penion

{{Short description|Genus of gastropods}} {{Automatic taxobox |fossil_range = Early Paleocene to Recent, {{fossilrange|66.0|0.0}} |image = Penion jeakingsi.png |image_caption = A siphon whelk ''Penion ormesi'',<ref name="Vaux 2020" /> collected from Golden Bay in New Zealand |taxon = Penion |authority = P. Fischer, 1884<ref>Fischer, P. 1884. Manuel de Conchyliologie et de Paléontologie Conchyliologique ou histoire naturelle des mollusques vivant et fossiles. Paris: F. Savy Vol. 7 pp. 609-688.</ref> |subdivision_ranks = Species |subdivision = See text |synonyms_ref = |synonyms = * ''Austrosipho'' Cossmann, 1906 * ''Austrosipho (Verconella)'' Iredale, 1914 * ''Berylsma'' Iredale, 1924<ref name="Iredale 1924">Iredale, T. 1924. ''Results from Roy Bell's molluscan collections''. Proceedings of the Linnean Society of New South Wales 49(3): 179-279, pls 33-36.</ref> * ''Largisipho'' Iredale, 1929 * ''Penion (Austrosipho)'' Cossmann, 1906 * ''Siphonalia (Penion)'' P. Fischer, 1884 superseded rank * ''Verconella'' Iredale, 1914<ref name="Iredale 1914">Iredale, T. 1914. ''On some invalid molluscan generic names.'' Proceedings of the Malacological Society of London 11: 170-178.</ref> }}

'''''Penion''''' is a genus of large marine snails, commonly known as '''siphon whelks''', classified within the mollusc family Austrosiphonidae.<ref name="WoRMS">{{WRMS species|488452|''Penion'' P. Fischer, 1884|16 April 2026}}</ref> <ref name="Vaux 2020">{{cite journal |doi=10.1093/sysbio/syaa018 |title=Lineage Identification Affects Estimates of Evolutionary Mode in Marine Snails |journal=Systematic Biology |volume=69 |issue=6 |pages=1106–1121 |year=2020 |last1=Vaux |first1=Felix |last2=Gemmell |first2=Michael R. |last3=Hills |first3=Simon F.K. |last4=Marshall |first4=Bruce A. |last5=Beu |first5=Alan G. |last6=Crampton |first6=James S. |last7=Trewick |first7=Steven A. |last8=Morgan-Richards |first8=Mary |pmid=32163159 }}</ref><ref name="Vaux-thesis">{{Cite thesis|title=Evolutionary lineages and the diversity of New Zealand true whelks|publisher=Massey University|date=2017|degree=Doctor of Philosophy|language=en|first=Felix|last=Vaux|hdl=10179/13113}}</ref><ref name="Vaux 2017B">{{cite journal |doi=10.1016/j.ympev.2017.06.018 |pmid=28669812 |title=A phylogeny of Southern Hemisphere whelks (Gastropoda: Buccinulidae) and concordance with the fossil record |journal=Molecular Phylogenetics and Evolution|volume=114 |issue=2017 |pages=367–381 |year=2017 |last1=Vaux |first1=Felix |last2=Hills |first2=Simon F.K. |last3=Marshall |first3=Bruce A. |last4=Trewick |first4=Steven A. |last5=Morgan-Richards |first5=Mary |bibcode=2017MolPE.114..367V }}</ref><ref name="Marshall 2018">{{cite journal |doi=10.1080/13235818.2017.1420398 |title=A new species of Penion P. Fischer, 1884 from northern New Zealand (Mollusca: Neogastropoda: Buccinoidea) |journal=Molluscan Research|volume=38 |issue=4 |pages=238–242 |year=2018 |last1=Marshall |first1=Bruce A. |last2=Hills |first2=Simon F.K. |last3=Vaux |first3=Felix |bibcode=2018MollR..38..238M |s2cid=90709310 }}</ref><ref name='Kantor-2022'>{{cite journal|author1=Kantor, Yuri I.|author2=Fedosov, Alexander E.|author3=Kosyan, Alisa R.|author4=Puillandre, Nicolas|author5=Sorokin, Pavel A.|author6=Kano, Yasunori|author7=Clark, Roger|author8=Bouchet, Philippe|title=Molecular phylogeny and revised classification of the Buccinoidea (Neogastropoda)|journal=Zoological Journal of the Linnean Society|year=2022|volume=194|issue=3|pages=789–857|doi=10.1093/zoolinnean/zlab031}}</ref>

==Description== [[File:Penion maximus (Tryon, 1881).jpg|left|thumb|An apertural view of a shell of ''Penion maximus'']] Siphon whelks are large, benthic marine snails, or whelks.<ref name="Marshall 2018" /><ref name="Powell 1979">Powell A. W. B., ''New Zealand Mollusca'', William Collins Publishers Ltd, Auckland, New Zealand 1979 {{ISBN|0-00-216906-1}}</ref><ref name="Willan 2010">Willan, R.C., de C. Cook, S., Spencer, H.G., Creese, R.G., O'Shea, S., Jackson, G.D. Phylum Mollusca. In: de C. Cook, S.C. (eds.), ''New Zealand Coastal Marine Invertebrates 1'', 406 – 407. Canterbury University Press, Christchurch, New Zealand {{ISBN|978-1877257-60-5}}</ref><ref name="Vaux 2017A">{{cite journal |doi=10.1080/13235818.2017.1279474 |title=Geometric morphometric analysis reveals that the shells of male and female siphon whelks ''Penion chathamensis'' are the same size and shape |journal=Molluscan Research|volume=37 |issue=3 |pages=194–201 |year=2017 |last1=Vaux |first1=Felix |last2=Crampton |first2=James S. |last3=Marshall |first3=Bruce A. |last4=Trewick |first4=Steven A. |last5=Morgan-Richards |first5=Mary |bibcode=2017MollR..37..194V |s2cid=90288210 }}</ref><ref name="Vaux 2018">{{cite journal |doi=10.1016/j.ympev.2018.06.009 |pmid=29913310 |title=Evolutionary lineages of marine snails identified using molecular phylogenetics and geometric morphometric analysis of shells |journal=Molecular Phylogenetics and Evolution|volume=127 |issue=October 2018 |pages=626–637 |year=2018 |last1=Vaux |first1=Felix |last2=Crampton |first2=James S.C. |last3=Trewick |first3=Steven A. |last4=Marshall |first4=Bruce A. |last5=Beu |first5=Alan G. |last6=Hills |first6=Simon F.K.|last7=Morgan-Richards |first7=Mary |bibcode=2018MolPE.127..626V |s2cid=49303166 }}</ref>

''Penion'' are commonly called siphon whelks because they have a very long siphon. Species typically have a large, pointed operculum.<ref name="Ponder 1973">Ponder, W.F. 1973. A review of the Australian species of ''Penion'' Fischer (Neogastropoda: Buccinidae). Journal of the Malacological Society of Australia 2: 401–428.</ref> Radulae have 3 or 4 cusps on lateral teeth and 3 cusps on central teeth.<ref name="Ponder 1973" />

Males have a long, dorso-ventrally flattened penis, and correspondingly females have a large pallial oviduct and albumen gland.<ref name="Ponder 1973"/> However, geometric morphometric investigation of ''P. chathamensis'' indicates that secondary sexual dimorphism is not prominent for shell shape or size.<ref name="Vaux 2017A"/>

Shells of ''Penion'' vary significantly in shape, size and colouration, making the distinction of species difficult.<ref name="Vaux 2020" /><ref name="Willan 2010" /><ref name="Vaux 2017A"/><ref name="Vaux 2018"/><ref name="Ponder 1973" /> Shells are fusiform with a tall spire of roughly equal height to the aperture and siphonal canal combined.<ref name="Ponder 1973"/> Protoconch morphology is also highly variable, from 1.5 - 4.0 whorls in height.<ref name="Ponder 1973" /> The siphonal canal of the shell is often long to protect the elongated siphon.<ref name="Ponder 1973" /> Small shells (or fossils) can be confused with those of ''Aeneator'' or ''Antarctoneptunea''.<ref name="Vaux 2018"/><ref name="Beu 1990">{{cite journal |last1=Beu |first1=Alan G. |last2=Maxwell |first2=P.A. |date=1990 |title=Cenozoic Mollusca of New Zealand |journal=NZGS Paleontological Bulletin |volume=58 |issue=5 |page=799 |url=https://www.gns.cri.nz/gns/Home/Our-Science/Land-and-Marine-Geoscience/Paleontology/Online-Resources/Cenozoic-Mollusca-of-New-Zealand |archive-date=2021-02-21 |access-date=2019-07-23 |archive-url=https://web.archive.org/web/20210221023347/https://www.gns.cri.nz/gns/Home/Our-Science/Land-and-Marine-Geoscience/Paleontology/Online-Resources/Cenozoic-Mollusca-of-New-Zealand |url-status=dead }}</ref>

Shell size can vary quite significantly among populations of ''Penion''. A species, ''Penion fairfieldae'' was formerly recognised, but recent genetic data has demonstrated that the species is indistinguishable from ''Penion chathamensis''.<ref name="Vaux 2020" /> Shells originally recognised as ''P. fairfieldae'' can be distinguished from ''P. chathamensis'' using shell size, but not using shell shape.<ref name="Vaux 2020" />

==Ecology== [[File:Penion sulcatus eggs1.jpg|right|thumb|Egg capsules of ''Penion sulcatus'' at Kawau Bay, Hauraki Gulf]] Most species occur in deep water,<ref name="Vaux 2017A"/><ref name="Vaux 2018"/> and inhabit soft sediments on the continental shelf.<ref name="Dell 1962">Dell, R.K. 1962. New Zealand Marine Provinces - do they exist? Tuatara, 10: 43 - 52. [http://nzetc.victoria.ac.nz/tm/scholarly/tei-Bio10Tuat01-t1-body-d8.html Online Copy courtesy of New Zealand Electronic Text Collection]</ref>

All species of ''Penion'' have a wide ranging diet, and are detritivores and carnivores that actively hunt prey.<ref name="Willan 2010" /><ref name="Vaux 2017A"/> ''P. sulcatus'' is known to feed on mussels and ''Dosina zelandica zelandica''.<ref name="Willan 2010" /><ref name="Wilson 1994">Wilson, B. 1994. ''Australian Marine Shells. Prosobranch Gastropods''. Kallaroo, WA : Odyssey Publishing Vol. 2 370 pp.</ref> Members of the genus have similar niche placement to species of ''Buccinum'' in the Northern Hemisphere.

==Distribution== ''Penion'' species are restricted to the Southern Hemisphere.<ref name="Vaux 2017A"/> Two extant species are currently classified in waters surrounding Australia<ref name="Ponder 1973" /> and five extant species are documented from New Zealand.<ref name="Vaux 2020" /><ref name="Vaux 2017B"/><ref name="Powell 1979"/><ref name="Vaux 2018"/>

Numerous fossil species are recorded in New Zealand,<ref name="Beu 1990"/><ref name="Hayward-2023">{{cite journal |doi=10.1080/00288306.2023.2243234 |title=A diverse Late Pliocene fossil fauna and its paleoenvironment at Māngere, Auckland, New Zealand |journal=New Zealand Journal of Geology and Geophysics |volume= 67|issue= 4|pages= 551–572|year=2023 |last1=Hayward|first1=Bruce W. |last2=Stolberger|first2=Thomas F. |last3=Collins|first3=Nathan |last4=Beu|first4=Alan G. |last5=Blom|first5=Wilma }}</ref> Australia,<ref name="Ponder 1973"/> Argentina and Chile,<ref name="Frassinetti 2000">{{cite journal |title=Upper Pliocene marine molluscks from Guafo Island, southern Chile. Part II. Gastropoda. |journal=Boletín del Museo Nacional de Historia Natural, Chile |volume=49 |pages=131–161 |year=2000 |last1=Frassinetti |first1=Daniel |doi=10.54830/bmnhn.v49.2020.353 |doi-access=free }}</ref><ref name="Reichler 2010">{{cite journal |doi=10.4067/S0718-71062010000100008 |title=Estratigrafía y paleontología del Cenozoico marino del Gran Bajo y Salinas del Gualicho, Argentina y descripción de 17 especies nuevas |journal=Andean Geology |volume=37 |issue=1 |pages=177–219 |year=2017 |last1=Reichler |first1=Valeria A. |doi-access=free }}</ref> and Antarctica.<ref name="Stilwell 1992">[http://onlinelibrary.wiley.com/book/10.1029/AR055 Stilwell, J.D., Zinsmeister, W.J. 1992. Molluscan systematics and biostratigraphy, lower Tertiary La Meseta Formation, Seymour Island, Antarctic Peninsula. American Geophysical Union Antarctica Research Series 55: 126-128. DOI: 10.1029/AR055] {{ISBN|9781118667705}}</ref><ref name="Beu 2009">{{cite journal |doi=10.1016/j.palaeo.2009.09.025 |title=Before the ice: Biogeography of Antarctic Paleogene molluscan faunas |journal=Palaeogeography, Palaeoclimatology, Palaeoecology |volume=284 |issue=3–4 |pages=191–226 |year=2009 |last1=Beu |first1=Alan G. |bibcode=2009PPP...284..191B }}</ref><ref name="Crame 2014">{{cite journal |doi=10.1371/journal.pone.0114743 |pmid=25493546 |title=The Early Origin of the Antarctic Marine Fauna and Its Evolutionary Implications |journal=PLOS ONE |volume=9 |issue=12 |article-number=e114743 |year=2014 |last1=Crame |first1=J. Alistair |last2=Beu |first2=Alan G. |last3=Ineson |first3=Jon R. |last4=Francis |first4=Jane E. |last5=Whittle |first5=Rowan J. |last6=Bowman |first6=Vanessa C.|pmc=4262473 |bibcode=2014PLoSO...9k4743C |doi-access=free }}</ref> In New Zealand, many fossils are found in Wanganui Basin sediments.<ref name="Beu 1990"/>

During the voyage of HMS ''Beagle'', fossils of ''P. subrectus'' were among palaeontological samples collected by Charles Darwin from the mouth of the Santa Cruz River in Argentina.<ref name="Parras 2009">{{cite journal |title=Darwin's great Patagonian Tertiary formation at the mouth of the Río Santa Cruz: a reappraisal |journal=Revista de la Asociación Geológica Argentina|volume=64 |issue=1 |pages=70–82 |year=2009 |last1=Parras |first1=Ana |last2=Miguel |first2=Griffin }}</ref>

==Evolution== [[File:Penion crawfordi rock.jpg|thumb|An embedded fossil of ''Penion crawfordi'' from Cape Palliser, New Zealand]] ''Penion'' is currently classified within Austrosiphonidae, a which is a family of large buccinoid whelks.<ref name='Kantor-2022' /> ''Penion'' has previously been classified within the families Buccinidae and Buccinulidae.<ref name="Vaux 2017B"/><ref name='Kantor-2022' /><ref name="Hayashi 2005">{{cite journal |title=The molecular phylogeny of the Buccinidae (Caenogastropoda: Neogastropoda) as inferred from the complete mitochondrial 16s rRNA gene sequences of selected representatives |journal=Molluscan Research |volume=25 |pages=85–98 |year=2005 |last1=Hayashi |first1=Seiji |issue=2 |doi=10.11646/mr.25.2.4 }}</ref>

{{cladogram|title=|align=center|caption=Cladogram of Austrosiphonidae and Tudiclidae<ref name="Vaux 2017B" /><ref name='Kantor-2022' /><ref name="Vaux 2018"/><ref name="Hayashi 2005"/> {{clade |style=font-size:100%; line-height:100%; |1={{clade |1={{clade |1=''Antarctoneptunea'' |2=''Kelletia'' |3=''Penion'' |4=''Serratifusus''}} }} |2={{clade |1=''Aeneator'' |2=''Buccinulum'' |3=''Euthria'' |4=''Tasmeuthria'' }} }} }} {{clear left}} Molecular phylogenetic trees based on mitochondrial genomic and nuclear ribosomal DNA sequence data indicate that ''Penion'' is closely related to two genera: ''Kelletia'' found in the north Pacific Ocean and ''Antarctoneptunea'', distributed in waters surrounding New Zealand and Antarctica.,<ref name="Vaux 2017B"/><ref name='Kantor-2022' /><ref name="Vaux 2018"/><ref name="Hayashi 2005"/> as well as ''Serratifusus''.<ref name='Kantor-2022' /> Radulae and opercula morphology is similar between ''Penion'' and ''Kelletia''.<ref name='Kantor-2022' /><ref name="Ponder 1973" /> It is possible that the earliest known fossils of ''Penion'' belonging to ''P. proavitus'' from the New Zealand Paleocene (Teurian), actually represent a stem lineage that was the common ancestor of these three genera.<ref name="Vaux 2017B" />

In Australian waters, the sister species ''P. mandarinus'' and ''P. maximus'' have overlapping geographic ranges (sympatry), and may have evolved from a common ancestor via niche differentiation based on prey size and water depth.<ref name="Vaux 2018"/>

In New Zealand, the extinct species ''Penion exoptatus'', ''Penion clifdenensis'', and potentially also ''Penion marwicki'', may belong to the same evolutionary lineage as the extant species ''Penion sulcatus''.<ref name="Vaux 2020" /> This hypothesis is based on geometric morphometric analysis of shell shape and size for all four taxa, as well as the analysis of morphometric variation exhibited all living species of ''Penion''.<ref name="Vaux 2020" />

==Human use== ''Penion'' shells are prized by shell collectors.

Shells found in middens of historic Māori settlements indicate that ''P. sulcatus'' may have been intentionally foraged as a food-source.<ref name="Green 1960">{{cite journal |title=Excavations at Orongo Bay, Gisborne |journal=The Journal of the Polynesian Society|volume=69 |issue=4 |pages=332–353 |year=1960 |last1=Green |first1=R.C. |last2=Pullar |first2=W.A.}}</ref><ref name="Allen 2012">{{cite journal |doi=10.1016/j.jas.2011.09.013 |title=Molluscan foraging efficiency and patterns of mobility amongst foraging agriculturalists: a case study from northern New Zealand |journal=Journal of Archaeological Science|volume=39 |issue=2012 |pages=295–307 |year=2012 |last1=Allen |first1=Melinda S. |bibcode=2012JArSc..39..295A |author1-link=Melinda S. Allen }}</ref>

==Species== [[File:Penion mandarinus1.jpg|thumb|''Penion mandarinus'' with eggs at Kennon Cove in Flinders]] [[File:Penion sulcatus live3.jpg|thumb|''Penion sulcatus'' near Goat Island, New Zealand with a damaged operculum]] Species and subspecies in the genus ''Penion'' include: {{div col|colwidth=25em}} * † ''Penion affixus'' (Finlay, 1930)<ref name="Beu 1990"/> * † ''Penion antarctocarinatus'' (Stilwell & Zinsmeister, 1992) * † ''Penion asper'' (Marwick, 1928)<ref name="Beu 1990"/> * † ''Penion australocapax'' Stilwell & Zinsmeister, 1992<ref name="Stilwell 1992"/><ref name="Beu 2009"/><ref name="Crame 2014" /> * † ''Penion bartrumi'' (Laws, 1941)<ref name="Beu 1990"/> * † ''Penion brazieri'' (Fleming, 1955)<ref name="Beu 1990"/> * ''Penion chathamensis'' (Powell, 1938)<ref name="Hayashi 2005"/> * † ''Penion clifdenensis'' (Finlay, 1930)<ref name="Beu 1990"/> * † ''Penion crassus'' Frassinetti, 2000<ref name="Frassinetti 2000"/> * † ''Penion crawfordi'' (Hutton, 1873)<ref name="Beu 1990"/> * † ''Penion crebissimus'' (I. Lea, 1833) * ''Penion cuvierianus'' (Powell, 1927)<ref name="Powell 1979"/><ref name="Beu 1990"/><ref name="Ponder 1975">Ponder, W.F. 1975. Identity of ''Penion dilatatus'' (Quoy & Gaimard, 1833) (Mollusca: Buccinidae). New Zealand Journal of Marine and Freshwater Research 9 (4): 569-571.</ref> * † ''Penion delabechii'' (I. Lea, 1833) * † ''Penion darwinianus'' (Philippi, 1887) <ref>{{cite book |last1=Philippi |first1=R.A. |title=Die Tertiären und Quartären Versteinerungen Chiles. iv + 266 pp + 58 pls |date=1887 |publisher=Brockhaus |location=Leipzig |page=247 |url=https://www.biodiversitylibrary.org/page/14943546 |access-date=21 April 2026}} {{source-attribution}}</ref> * † ''Penion diversus'' Frassinetti, 2000<ref name="Frassinetti 2000"/> * † ''Penion domeykoanus'' (Philippi, 1887)<ref name="Ponder 1973"/> * † ''Penion exoptatus'' (Powell & Bartrum, 1929)<ref name="Beu 1990"/> * † ''Penion finlayi'' (Laws, 1930)<ref name="Beu 1990"/> * † ''Penion gauli'' (Marwick, 1948)<ref name="Beu 1990"/> * † ''Penion haweraensis'' (Powell, 1931)<ref name="Beu 1990"/> * † ''Penion hiatulus'' (Powell, 1947)<ref name="Beu 1990"/> * † ''Penion huttoni'' (L.R. King, 1934)<ref name="Beu 1990"/> * † ''Penion imperfectus'' (Powell, 1947)<ref name="Beu 1990"/> * † ''Penion interjunctus'' (Finlay, 1930)<ref name="Beu 1990"/> * † ''Penion koruahinensis'' (Powell & Bartrum, 1928)<ref name="Beu 1990"/> * ''Penion lineatus'' Marshall, Hills & Vaux, 2018<ref name="Marshall 2018" /><ref name="Vaux 2018"/> * † ''Penion longirostris'' (Tate, 1888)<ref name="Ponder 1973"/> * † ''Penion macsporrani'' (Philippi, 1887) * ''Penion mandarinus'' (Duclos, P.L., 1831)<ref name="Ponder 1973"/> * † ''Penion marwicki'' (Finlay, 1930)<ref name="Beu 1990"/> * ''Penion maximus'' (Tryon, G.W., 1881)<ref name="Ponder 1973"/> * † ''Penion oncodes'' (Philippi, 1887) * ''Penion ormesi'' (Powell, 1927) * † ''Penion parans'' (Finlay, 1930)<ref name="Beu 1990"/> * † ''Penion patagonensis'' Reichler, 2010<ref name="Reichler 2010"/> * † ''Penion petitianus'' (d'Orbigny, 1842) * † ''Penion proavitus'' (Finlay & Marwick, 1937)<ref name="Beu 1990"/> * † ''Penion roblini'' (Tenison Woods, 1876)<ref name="Ponder 1973"/> * † ''Penion spatiosus'' (Tate, 1888)<ref name="Ponder 1973"/> * † ''Penion subrectus'' (Ihering, 1899)<ref name="Ponder 1973" /><ref name="Parras 2009"/> * † ''Penion subreflexus'' (G.B. Sowerby I, 1846)<ref name="Ponder 1973" /> * † ''Penion subregularis'' (d'Orbigny, 1852) * ''Penion sulcatus'' (Lamarck, 1816)<ref name="Powell 1979"/><ref name="Beu 1990"/><ref name="Hayashi 2005"/> * † ''Penion winthropi'' (Marwick, 1965)<ref name="Beu 1990"/> {{div col end}}

===''Nomina dubia''=== Beu 2009 lists the following Antarctic fossil species as nomina dubia: * † ''Penion gazdzicki'' (Karczewski, 1987), previously ''Neptunea'' and ''Beringius'', potentially ''Antarctoneptunea''<ref name="Beu 2009"/>

===Species brought into synonymy=== * ''Penion adustus'' (Philippi, 1845): synonym of ''Penion sulcatus'' (Lamarck, 1816)<ref name="Ponder 1975" /> * ''Penion cuvierianus jeakingsi'' (Powell, 1947):<ref name="Powell 1979"/> synonym of ''Penion ormesi'' (Powell, 1927)<ref name="Vaux 2020" /> * ''Penion dilatatus'' (Quoy & Gaimard, 1833): synonym of ''Penion sulcatus'' (Lamarck, 1816)<ref name="Ponder 1975" /> * ''Penion fairfieldae'' (Powell, 1947):<ref name="Powell 1979"/><ref name="Beu 1990"/> synonym of ''Penion chathamensis'' (Powell, 1938)<ref name="Vaux 2020" />

===Reclassified species=== * ''Penion benthicolus'' Dell, 1956: accepted as ''Antarctoneptunea benthicola'' (Dell, 1956)<ref name="Vaux 2017B" />

== References== {{Reflist}}

==External links== {{Commons category|Penion}} * [http://collections.tepapa.govt.nz/Taxon/51186 Museum of New Zealand Te Papa Tongarewa, Taxon: ''Penion'' (Genus)] * [http://www.aucklandmuseum.com/collections-research/collections/search/?srt=score&class=Penion Auckland War Memorial Museum: ''Penion'' specimens] * [http://www.gns.cri.nz/static/Mollusca/index.html Revised descriptions of New Zealand Cenozoic Mollusca from Beu and Maxwell (1990)] {{Webarchive|url=https://web.archive.org/web/20210127064452/http://www.gns.cri.nz/static/Mollusca/index.html |date=2021-01-27 }} * [http://www.molluscs.otago.ac.nz/ Checklist of the Recent Mollusca Recorded from the New Zealand Exclusive Economic Zone] * [http://www.molluscsoftasmania.net/Genus%20pages/Penion.html Molluscs of Tasmania: Buccinidae - Siphonaliinae: Genus ''Penion'' Fischer, 1884 - "whelks"]

==Further reading== * Powell A. W. B., ''New Zealand Mollusca'', William Collins Publishers Ltd, Auckland, New Zealand 1979 {{ISBN|0-00-216906-1}}

Category:Penion Category:Extant Miocene first appearances Category:Taxa named by Paul Henri Fischer