Global and European regional assessment: Near Threatened (NT)
EU 27 regional assessment: Near Threatened (NT)

Cerophytum elateroides is rare throughout its range and has a fragmented distribution. The main population occurs in the EU27 region while the species is rare in the other countries of Europe. It needs old dead trees of large diameters or high volumes of dead wood, those elements are often removed from the forests or parks and the suitable habitat is continually declining. The extent of occurrence (EOO), is extremely large but the species is observed only as very small and isolated subpopulations. Even in a locality it is present only in specific micro-habitats. Its known area of occupancy (AOO) is 772 km² globally and 668 km² in the EU27 region. Neither value is expected to exceed 2,000 km² if more localities are found. The habitat is continually declining, therefore this species is assessed as Near Threatened both globally and in the EU27 region as it is close to qualifying as threatened under criterion B2b(iii).

Cerophytum elateroides is endemic to Europe where it is widespread, mostly in the centre and the south (Costa et al. 2003, Mertlik 2008, Dušánek 2014).

Its native presence in southern Britain, although considered (Allen 1969), has never been confirmed and it is no longer indicated for the country (Duff 2012, Mendel 2017). Largely distributed in France (Dodelin and Leseigneur 2010), it reaches a western limit in the northeast of Spain with only two localities known in this country (Pérez-Moreno and Recalde Irurzun 2010, Recalde Irurzun and San Martin Moreno 2012).

In the north, it becomes very rare and sporadic in northern Germany (Luch 1979). In Belgium, it has been re-discovered recently after ~80 yrs without any observations (Troukens 2017). In Hungary this species is very rare, and occurs mostly in the hilly regions and riparian forests of the western part of the country (O. Merkl pers. comm. 2009). In Czechia there are several known localities and recent records in eastern Slovakia. In Italy, it seems to be restricted in the north of the country and no recent data are available. In Poland it is reported from an unique locality from where it is likely to have become extinct (Burakowski and Śliwiński 1981). However, it is not improbable that a small population of this beetle persists somewhere in the south of the country (Głowaciński and Nowacki 2009). The presence in Bulgaria was first indicated in the Catalogue of Palaearctic Coleoptera probably after a technical error, a misprint of BU (Bulgaria) instead of BE (Belgium). But the true species' presence there has been confirmed recently (Teofilova et al. 2021). In Ukraine, it occurs only in few localities of the Carpathians (Mateleshko 2008). In European Russia, it seems very sparsely distributed, in locations far apart from each other, from the Moscow region to Samara. But precise information are difficult to find for this country.

This species is rare over much of its range. In many countries, it is known only from a few localities, or it is located in only a small part of the country (Hungary, Italy, Ukraine, Romania, Bulgaria, Serbia, Moldova, European Russia). The most important populations are found in the riparian forests of the large rivers (Rhône, Rhine, Danube), or in hilly regions of France and central Europe. In Switzerland, the species is currently known from only nine subpopulations (A. Sanchez pers. comm. 20024, Info Fauna).

In Poland it is likely to have become extinct (Głowaciński and Nowacki 2009). In the UK, if native then now the species is extinct.

Cerophytum elateroides is an obligate saproxylic species. It is usually found in open forests, in cities' old parks, in floodplain forests and in large trees of hedgerows. In Switzerland, localities are as diverse as a cool, north-facing beech forest (Sanchez and Chittaro 2021), and a thermophilic open chestnut grove (Chittaro and Sanchez 2016). It has been regarded as a typical old forest relic (Allen 1969, Eckelt et al. 2018) and as an indicator of high quality forests in France (Brustel 2005), and in Switzerland (Sanchez et al. 2016).

The development takes place in decaying wood of old broad-leaved trees, mainly large Populus trees, and also Acacia, Acer, Aesculus, Alnus, Betula, Carpinus, Castanea sativa, Fagus, Juglans, Platanus, Quercus, Salix, Tilia, Ulmus, etc. (Sanchez et al. 2018). The larvae have been re-described recently by Costa et al. (2003). It does not favour the tree species, but a specific wood quality with the right stage of decay and mycelium of peculiar fungi (Dušánek 2014). Pupation takes place in wood mould, especially in tree cavities at the trunk basis, in a shell similar to that of the Cetoniidae (Dupont and Courtin 2017). The adults emerge very early in spring, which makes them rather difficult to observe.

Interruption of the continuous supply of suitable dead wood (ecological continuity) is a threat to this species, as this species needs a high volume of dead wood. It is largely confined to old-growth forests and parkland with ancient trees. Often there is no replacement for these trees once they die off. Regulation of water levels in floodplains reduces the amount of falling dead trees and therefore the habitat.

In Hungary habitat loss may occur in several localities, but owing to the rarity of the species it is difficult to study the threatening factors (O. Merkl pers. comm. 2009).

Saproxylic Coleoptera tend to be popular with beetle collectors although trade is rarely an issue, the only exceptions being a few larger species of more dramatic form or colour.

Preservation of old-growth forest and dead wood is recommended to provide habitat continuity for this species. The species occurs in several protected areas (e.g. in Hungary, France, and the Carpathian Mountains). This species is considered Endangered in Poland (Głowaciński and Nowacki 2009) and Germany (Schaffrath 2021). It is Data Deficient in Italy (Carpaneto et al. 2015) and Vulnerable in the Auvergne-Rhône-Alpes region (France) (Dodelin and Calmont 2021). In Switzerland, it is "emblematic", i.e. a species with a high conservation value (Sanchez et al. 2016).