Oonotus sericeus

Assessor: Riaan Stals

Sensitive in 2010
Reason for the sensitivity status
Wild specimens of this genus are known to be targeted and exploited for international trade as seen on online marketplaces. Trade in dead and alive stag beetles causes population decline and this species has a vulnerable population size, were exploitation to occur, the whole extant population could be harvested and recovery may not be possible. Releasing data on this species can exacerbate threat and vulnerability.
This species is either similar to another sensitive species or belongs to a group containing sensitive species, and is extremely rare in the wild. The localities of wild populations need to be protected to avoid loss to exploitation, which, due to its rarity, could drive the species to extinction within a very short time.
Exploitation extent
Uncertain - No data exists yet showing that this species is exploited in the wild, however it has one or more relatives or look-alike species (found in South Africa or globally) that are known to be utilised. This species has a similar life form or other relevant traits to its exploited relative(s), making it highly likely that it would be exploited for the same purposes.
Justification and references


1. Taxonomy

Oonotus (Macroonotus) sericeus Endrödy-Younga, 1993

FAMILY Lucanidae (stag beetles)

English: Silky Small Stag Beetle

iSiZulu: iNkubabulongwe

Taxon concept: The species concept employed here is that of Endrödy-Younga (1993), which is the original species description..



2. Prior, existing or proposed conservation status


2.1. IUCN Red List of Threatened Species

First evaluation in May 2011. Submitted to IUCN, but unpublished.

Red List Status: Data Deficient (distribution): DD-D.


  • Endemic to the Republic of South Africa. Known from only one specimen, collected in 1937. 

  • Not enough is known about the habitat and biology of this species to formally assess it.

  • Under potential collection pressure to supply the beetle collector's trade.

  • Potentially threatened.

REFERENCE: Stals, Armstrong & Raimondo (2011d)


2.2. Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES)


REFERENCE: CITES Appendices valid from 2017-10-04.


2.3. Threatened or Protected Species (ToPS) list, 2007

Listed in category: Protected Species.


2.4. Threatened or Protected Species (ToPS) list, revised 2011 (unpublished)

•• Revised lists published for public comment: Notice 389 of 2013, Government Gazette No. 36375, 16 April 2013.



2.5. National Sensitive Species List, 2010



2.6. KwaZulu-Natal Environmental, Biodiversity and Protected Areas Management Bill, 2014 (draft)

Listed in Schedule 3 as Protected Animal Species.



3. Exploitation extent

Specimens of any and all Lucanidae (stag beetles) have for many decades been probably the most sought-after beetles among armchair and safari collectors in affluent communities. A simple Google search will reveal the enormous extent of international trade in stag beetles, both as dead, preserved specimens and as livestock. Four clear trends are, and have always been, discernible in the trade of collectable beetles:

  1. Larger beetle species are more valuable than smaller species and command higher prices; and there is more trade in larger species than in smaller species.
  2. Larger individual specimens within any collectable beetle species are more valuable than smaller specimens and command higher prices; and there is more trade in larger specimens than in smaller specimens.
  3. Rare, scarce and other difficult-to-obtain beetle species are more valuable than commoner species or species that are easier to obtain, and rare and scarce beetle species command higher prices.
  4. There is a synergistic interaction among the above three variables.


The species of the stag beetle genus Oonotus are small beetles, leading to them not being highly popular among purchasing or poaching collectors. This situation may however change, for the following reasons, among others:

  1. Wealthy armchair and safari collectors of insects have a general aim to own a "complete" collection, meaning representative specimens of all the species and subspecies within a focal taxonomic group, in this case the family Lucanidae (stag beetles). Some collectors have a worldwide interest, whereas the interest of others may focus on one of more specific geographic areas, e.g. Africa. In pursuit of "complete" collections, they will necessarily also wish to purchase or collect smaller-bodied species, such as those of Oonotus.
  2. Some of the Oonotus species are demonstrably among the rarest of all stag beetles, with Oonotus sericeus outperforming all the others therein that only a single specimen of that species has ever been collected (as far as it has been made known).
  3. For perhaps more than a century and a half already, "gentleman collectors" have been advised of what species are potentially available for them to obtain through catalogues, more often than not published by purveyors of deadstock. This practice reached its pinnacle with the luxurious, beautiful and exceptionally expensive books published since 1999 by Taita Publishers in the Czech Republic.
         The books published by Taita clearly serve both as appetisers for the wealthy beetle collector and as modern shopping catalogues, brilliantly illustrated with large photographs on thick glossy paper, representing the gamut of what an armchair collector would like to buy for his collection in order for it to become "complete". It is telling that the cofounder of Taita Publishers, as well as its most prolific author, was the late Karl 'Charly' Werner, somebody who was an unashamed beetle dealer and who over decades spent large amounts of time in Africa collecting rare beetles [or purportedly rare beetles] to sell at astonishing prices in the northern hemisphere. Werner never made any secret of his occupation and the source of his wealth.
         For the Lucanidae (stag beetles) of the Afrotropics, Taita published in 2004 a truly magnificent book (Bartolozzi & Werner 2004) in which the genus Oonotus was made known to collectors worldwide for the first time, "advertised" with large and magnificent photographs of all four known species. Because of this book, my coleopterist colleagues and I suspect that specimens of Oonotus, despite being small, have now moved into the visor of those that sustain the demand for rare collectable beetles. Previously they were obscure and known only to those that peruse the primary taxonomic literature. I suspect that trade in Oonotus specimens may be much larger than what I could find evidence for (below).


Evidence for trade in Oonotus species

I could not find evidence of trade in, or commercial collection of, Oonotus sericeus. It appears that still only one specimen (the holotype, collected in 1937) of the species is known, as recorded by Endrödy-Younga (1993) and repeated by Bartolozzi & Werner (2004).

I have no evidence for trade in any Oonotus specimens besides that below.


During January and February 2018 I scoured the internet for instances where any Oonotus specimens were offered for sale, or where a such a transaction had been concluded. I found only a single such instance.

(1) One specimen of Oonotus adspersus offered for sale on the 'eurofauna.com' website by a person apparently based in China.

»»» Click HERE for a permanently archived cache of that webpage.


(◘) I did locate another instance which is a smoking gun. Colin R. Owen of Somerset West, South Africa, has been known as a beetle dealer since at least 1985 (documentation in my care). He operates the website beetlesofafrica.com, which is a display of what must be Africa's most sought-after beetles (for an armchair or safari collector). Only a small number of the beetle species displayed on Owen's website are on the site itself offered for sale. Displayed on Owen's website is the species Oonotus interioris (misspelled as "Oonutus interioris"), but this species is not offered for sale on the site itself.

»»» Click HERE for a permanently archived cache of that webpage.

On this webpage the detailed collecting data of the displayed specimen is given. The most intriguing part of this detective story is that a photo of a specimen of this species (but not the same specimen!) with exactly the same collecting data, but with added that the specimen was collected by C.R. Owen, appears on page 21 of the luxurious catalogue by Bartolozzi & Werner (2004). The specimen figured in the book is credited to [now] belong to the collection of Luca Bartolozzi, Florence, Italy.

This is not conclusive evidence of any beetles having been sold, but it is a smoking gun.


(◘) Another smoking gun is the photographs of two other, different, specimens of Oonotus interioris that appear on the same page 21 of Bartolozzi & Werner (2004). On that page it is stated that both specimens were collected by a South African citizen suspected to be a beetle dealer, but whose name I shall not divulge here. Both those specimens are credited to having belonged to the collection of Karl Werner, Peiting, Germany (see above). Werner passed away after the publication of this book.

Again this is not conclusive of commercial dealing in any beetles, but it is another smoking gun.

According to Taxon Lead (Stals, R, personal communication 2018, 28 February), this genus is at risk and sensitive to over-exploitation which means this species and its others may be at risk to and should be categorized as senstive. There is a potential illegal market for all the Oonotus species. Oonotus rex is thought to be desirable to collectors as only two specimens of the species are known to humankind. Oonotus sericeus is only known from its holotype. The localities where the three specimens of these two species were collected are published in the revision of Endrödy-Younga (1993) and hence known, but the species have never been recollected. These beetles are not difficult to find if one knows something about their ecology, which happens to be unpublished. And the non-collection of these beetles is despite anecdotes of people going on expeditions looking for specifically those species. In principle the same holds for the other two species. It is likely that additional areas of habitat where these beetle species occur will be discovered. It is also possible that the "known" localities of the two enigmatically scarce species are wrong (for any of a number of reasons), and that the "true" localities where they occur will be found. Please also note in my motivations for Oonotus adspersus and Oonotus interioris that there are several localities known to a select few coleopterists as harbouring these species, but that this information has never been made public.

4. References

Bartolozzi L, Werner K (2004) Illustrated Catalogue of the Lucanidae from Africa and Madagascar. Taita Publishers, Hradec Králové, Czech Republic. 191 pp. Book homepage at publisher.

Endrödy-Younga S (1993) The southern African lucanid genus Oonotus Parry with descriptions of a new subgenus and three new species (Coleoptera: Scarabaeoidea). Annals of the Transvaal Museum 36(5): 31–40. Persistent link.

Stals R, Armstrong AJ, Raimondo D (2011d) Oonotus sericeus. IUCN Red List Assessment. Submitted to IUCN, but unpublished. On file with the South African National Biodiversity Institute (SANBI).

Population vulnerability
Population is vulnerable: size is <= 2500 mature individuals OR the number of known subpopulations is <= 5 OR range is <= 100km2 OR species at risk of localised extinctions
Justification and references

The population of Oonotus interioris is vulnerable for the following reason:

  1. The species is known from only one location, from which only one specimen (the holotype) is known.
  • The population size is unknown.
  • The range of the species cannot be determined, since only one specimen is known to humankind.

REFERENCE: Stals R, Armstrong AJ, Raimondo D (2011d) Oonotus sericeus. IUCN Red List Assessment. Submitted to IUCN, but unpublished. On file with the South African National Biodiversity Institute (SANBI).

Targeted demographics
Mature (breeding) individuals are killed, significantly weakened or are permanently removed from the wild, OR immature individuals are targeted and this significantly impacts mature (breeding) individuals.
Regeneration potential
This species has a slow population growth rate, or the growth rate varies depending on habitat, and there is a poor chance the wild populations will recover from exploitation OR a collector might feasibly harvest the entire extant population removing the chance of subsequent recruitment.
Justification and references

No information exists about the regeneration potential of this species. However as this species is known from one location, were exploitation to occur, its entire extant population could be harvested.