''Dematochroma'' is a genus of

leaf beetle The beetle family Chrysomelidae, commonly known as leaf beetles, includes over 37,000 (and probably at least 50,000) species in more than 2,500 genera, making it one of the largest and most commonly encountered of all beetle families. Numerous s ...

s in the subfamily

Eumolpinae The Eumolpinae are a subfamily of the leaf beetles, or Chrysomelidae. It is one of the largest subfamilies of leaf beetles, including more than 500 genera and 7000 species. They are oval, and convex in form, and measure up to 10 mm in size. ...

. It is mostly distributed in

New Caledonia New Caledonia ( ; ) is a group of islands in the southwest Pacific Ocean, southwest of Vanuatu and east of Australia. Located from Metropolitan France, it forms a Overseas France#Sui generis collectivity, ''sui generis'' collectivity of t ...

, though it is also found on

Lord Howe Island Lord Howe Island (; formerly Lord Howe's Island) is an irregularly crescent-shaped volcanic remnant in the Tasman Sea between Australia and New Zealand, part of the Australian state of New South Wales. It lies directly east of mainland Port ...

Norfolk Island Norfolk Island ( , ; ) is an States and territories of Australia, external territory of Australia located in the Pacific Ocean between New Zealand and New Caledonia, directly east of Australia's Evans Head, New South Wales, Evans Head and a ...

Timor Timor (, , ) is an island at the southern end of Maritime Southeast Asia, in the north of the Timor Sea. The island is Indonesia–Timor-Leste border, divided between the sovereign states of Timor-Leste in the eastern part and Indonesia in the ...

and

Vanuatu Vanuatu ( or ; ), officially the Republic of Vanuatu (; ), is an island country in Melanesia located in the South Pacific Ocean. The archipelago, which is of volcanic origin, is east of northern Australia, northeast of New Caledonia, east o ...

. Adult beetles (usually less than 1 cm long) are often found at night feeding on leaves, and the larvae eat roots.

Phylogeny

Recent phylogenetic analyses of Eumolpinae of the south Pacific suggest that ''Dematochroma'' is

paraphyletic Paraphyly is a taxonomic term describing a grouping that consists of the grouping's last common ancestor and some but not all of its descendant lineages. The grouping is said to be paraphyletic ''with respect to'' the excluded subgroups. In co ...

: the type species, the Lord Howe endemic ''D. picea'', is placed in a clade including New Caledonian endemic genera ''

Taophila ''Taophila'' is a genus of leaf beetles in the subfamily Eumolpinae. The genus is endemic to New Caledonia. Taxonomy ''Taophila'' was first established in 1916 by the Austrian entomologist Karl Borromaeus Maria Josef Heller for a single describe ...

'' and '' Tricholapita'', which is sister to another clade including other New Caledonian Eumolpinae genera, the New Caledonian species of ''Dematochroma'' as well as the New Zealand endemic '' Atrichatus''. Because of such findings, Gómez-Zurita and collaborators have preferred to transfer several New Caledonian species of ''Dematochroma'' to other genera. For instance, the genus ''

Thasycles ''Thasycles'' is a genus of leaf beetles in the subfamily Eumolpinae. It is endemic to New Caledonia. For a long time it was treated as a synonym of ''Dematochroma'', until it was reinstated as a valid genus in 2022. Species Eleven species are i ...

'' Chapuis, 1874, which was for a long time treated as a synonym of ''Dematochroma'', was reinstated as a valid genus, and a new genus '' Dematotrichus'' was established for ''Dematochroma pilosa'' and closely related species.

Species

* ''

Dematochroma antipodum ''Dematochroma'' is a genus of leaf beetles in the subfamily Eumolpinae. It is mostly distributed in New Caledonia, though it is also found on Lord Howe Island, Norfolk Island, Timor and Vanuatu. Adult beetles (usually less than 1 cm long) a ...

'' ( Fauvel, 1862) – New Caledonia * '' Dematochroma antipodumoides'' Jolivet, Verma & Mille, 2010 – Vanuatu * '' Dematochroma culminicola'' ( Heller, 1916) – New Caledonia * '' Dematochroma difficilis'' ( Heller, 1916) – New Caledonia * '' Dematochroma doiana'' Jolivet, Verma & Mille, 2007 – New Caledonia * '' Dematochroma helleri'' Jolivet, Verma & Mille, 2007 – New Caledonia * '' Dematochroma howensis'' Jolivet, Verma & Mille, 2006 – Lord Howe Island * '' Dematochroma lepros'' ( Heller, 1916) – New Caledonia * '' Dematochroma maculifrons'' ( Heller, 1916) – New Caledonia * ''

Dematochroma norfolkiana ''Dematochroma'' is a genus of leaf beetles in the subfamily Eumolpinae. It is mostly distributed in New Caledonia, though it is also found on Lord Howe Island, Norfolk Island, Timor and Vanuatu. Adult beetles (usually less than 1 cm long) a ...

'' Jolivet, Verma & Mille, 2006 – Norfolk Island * '' Dematochroma picea'' Baly, 1864 – Lord Howe Island * ''

Dematochroma samuelsoni ''Dematochroma'' is a genus of leaf beetles in the subfamily Eumolpinae. It is mostly distributed in New Caledonia, though it is also found on Lord Howe Island, Norfolk Island, Timor and Vanuatu. Adult beetles (usually less than 1 cm long) a ...

'' Jolivet, Verma & Mille, 2011 – New Caledonia * '' Dematochroma shuteae'' Jolivet, Verma & Mille, 2006 – Norfolk Island * '' Dematochroma sylviae'' Jolivet, Verma & Mille, 2010 – New Caledonia * '' Dematochroma terastiomerus'' ( Heller, 1916) – New Caledonia * '' Dematochroma terminaliae'' Jolivet, Verma & Mille, 2010 – New Caledonia * '' Dematochroma theryi'' Jolivet, Verma & Mille, 2010 – New Caledonia * '' Dematochroma timorense'' Jacoby, 1894 – Timor The following species are synonyms: * ''Dematochroma poyensis'' Jolivet, Verma & Mille, 2010: synonym of '' Dematochroma theryi'' Jolivet, Verma & Mille, 2010 * ''Dematochroma soldatii'' Jolivet, Verma & Mille, 2010: synonym of '' Dematochroma antipodumoides'' Jolivet, Verma & Mille, 2010 The following species have been transferred to other genera: * ''Dematochroma cancellata'' (Samuelson, 2010): transferred to '' Cazeresia'', as synonym of '' Cazeresia striata'' (Jolivet, Verma & Mille, 2007) * ''Dematochroma foaensis'' Jolivet, Verma & Mille, 2007: transferred to '' Rhyparida'' * ''Dematochroma fusca'' Jolivet, Verma & Mille, 2007: transferred to ''

'' * ''Dematochroma humboldtiana'' ( Heller, 1916): transferred to '' Cazeresia'' * ''Dematochroma laboulbenei'' ( Montrouzier, 1861): transferred to ''

'' * ''Dematochroma panieensis'' Jolivet, Verma & Mille, 2007: transferred to ''

'' * ''Dematochroma pilosa'' Jolivet, Verma & Mille, 2007: transferred to '' Dematotrichus'' * ''Dematochroma thyiana'' Jolivet, Verma & Mille, 2008: transferred to '' Cazeresia''

References

External links

Genus ''Dematochroma'' Baly, 1864
at

Australian Faunal Directory The Australian Faunal Directory is an online catalogue of taxonomic and biological information on all animal species known to occur within Australia. It is a database produced by the Department of Climate Change, Energy, the Environment and Water ...

Eumolpinae Chrysomelidae genera Beetles of Oceania Beetles of Australia Insects of New Caledonia Taxa named by Joseph Sugar Baly {{Eumolpinae-stub