An illustrated catalogue of South American species of Omorgus Erichson, 1847 (Coleoptera, Trogidae, Omorginae) including a neotype designation and taxonomical changesAuthorda Costa-Silva, Vinícius0000-0002-4556-3793Department of Zoology & Entomology, University of Pretoria, Private Bag X 20, Hatfield, 0028, South Africa & Laboratório de Scarabaeoidologia, Instituto de Biociências, Universidade Federal de Mato Grosso (UFMT), Cuiabá, Mato Grosso, BrazilAuthorStrümpher, Werner P.0000-0002-7047-2666Ditsong National Museum of Natural History, PO Box 413, Pretoria 0001, South AfricaAuthorBarclay, Maxwell V. L.0000-0003-4989-2014Department of Life Sciences, Natural History Museum, London SW 7 5 BD, UKAuthorVaz-de-Mello, Fernando Z.0000-0001-9697-320XLaboratório de Scarabaeoidologia, Instituto de Biociências, Universidade Federal de Mato Grosso (UFMT), Cuiabá, Mato Grosso, BraziltextContributions to Entomology20242024-07-2974181101journal article10.3897/contrib.entomol.74.e126799339AB68C-DCB1-435F-B88E-2C42D0A7B05EOmorgus
(
Omorgus
)
suberosus
(
Fabricius, 1775
)
Fig. 7Trox suberosusFabricius, 1775: 31
(original description);
Fabricius 1781: 34
(diagnosis);
Fabricius 1787: 18
(diagnosis);
Olivier 1789: 6
(diagnosis);
Gmelin 1790: 1586
(diagnosis);
Herbst 1790: 29
(description);
Fabricius 1792: 87
(diagnosis);
Fabricius 1801: 111
(diagnosis);
Illiger 1802: 332
(catalogue);
Schönherr 1806: 118
(catalogue);
Castelnau 1840: 107
(as ‘
tuberosus
’ – misspelling);
Sturm 1843: 112
(checklist);
Blanchard 1847: 190
(catalogue);
Lacordaire 1856: 151
(type designation of
Omorgus
)
Harold 1869: 1090
(checklist);
Harold 1872: 119
(redescription);
Horn 1874: 5
(diagnosis, comments);
Burmeister 1876: 257
(diagnosis);
Berg 1881: 99
(checklist);
Arrow 1903: 516
(notes about fauna of the
St. Vincent Island
);
Bruch 1911: 194
(checklist);
Leng 1920: 253
(catalogue);
Mutchler 1925: 238
(catalogue of Galapagos Islands);
Blatchley 1928: 64
(records for Florida);
Leng 1928: 422
(catalogue of New York); Sim 1934: 11 (larvae description);
Denier 1936: 205
(natural history);
Hayward 1936: 217
(feeding habit);
Blackwelder 1944: 219
(catalogue – as ‘
suberosa
’);
Van Dyke 1953: 123
(distribution data);
Haaf 1954: 739
(catalogue of
Australia
);
Vaurie 1955: 60
(redescription);
Howden and Vaurie 1957: 4
(pronotum and aedeagus drawing);
Ritcher 1958: 325
(biology);
Vaurie 1962: 144
(redescription);
Landin 1963: 4
(record from
Cape Verde
Is.);
Zimsen 1964: 38
(catalogue);
Ritcher 1966: 73
(biology);
Hatch 1971: 464
(key to the Pacific Northwest beetles);
Chalumeau and Gruner 1974: 787
(catalogue of French Antilles);
Paulian 1981: 4
(larvae morphology);
Young and Hamm 1985: 93
(feeding experiment);
Young 2006: 271
(biology);
Bouchard et al. 2024: 372
(mentioned as type species).
Trox
(
Omorgus
)
suberosus
:
Burmeister 1876: 257
(redescription);
Arrow 1912: 62
(catalogue);
Scholtz 1982: 13
(systematics).
Omorgus suberosus
:
Erichson 1847: 111
(new combination);
Baker 1968: 42
(larvae’s description);
Chalumeau 1977: 231
(corrigenda);
Scholtz 1986 a
: 361
(phylogenetics);
Scholtz 1986 b
: 54
(distribution from
Australia
);
Scholtz 1990: 1407
(redescription);
Ratcliffe 1991: 157
(redescription);
Baraud 1992: 24
(diagnosis);
Browne et al. 1993: 199
(phylogeny);
Muñoz-Batet and Lopez-Colon 1995: 279
(record from
Czech Republic
);
Páramo 1997: 29–31
(distribution); Costa et al. 1988: 109 (larvae description and illustration);
Deloya 2000: 69
(checklist);
Ratcliffe 2002: 8
(checklist from
Panama
); Rosano-Hernandes and Deloya 2002: 32: (natural history);
Morón 2003: 408
(checklist);
Deloya 2003: 132
(diagnosis and distribution);
Diéguez and Gómez 2004: 94
(checklist);
Deloya 2005: 122
(checklist);
Nikolajev 2005: 322
(larvae characteristics);
Löbl and Smetana 2006: 79
(catalogue);
Lopes et al. 2007
:
Mora-Aguilar and Montes de Oca 2009: 575
(distribution);
Philips 2009: 4
(association with mites);
Krell 2010: 4
(checklist);
Carvajal et al. 2011: 161
(checklist);
Zidek 2013: 17
(checklist);
Verdugo 2014: 212
(mention);
Ratcliffe 2015: 189
(checklist from
Peru
);
Ziani et al. 2015: 3
(distribution);
Baena et al. 2015: 2
, 4 (feeding behaviour);
Pittino and Bezdĕk 2016: 54
(checklist);
Strümpher et al. 2016: 57
(phylogeny);
Zidek 2017: 109
(checklist);
Smith 2017: 87
(notes, distribution);
Cortez et al. 2017: 4
(natural history);
Huchet and Costa-Silva 2018: 565
(new distribution records from South America);
Hielkema and Hielkema 2019
(checklist of the Guianas);
Miquel 2019: 184
, 186 (distribution);
Giraldo-Mendoza 2021: 64
(checklist from
Peru
);
Costa-Silva et al. 2021: 2008
(review of Brazilian species).
Omorgus
(
Omorgus
)
suberosus
:
Gianizella and Prado 1999: 749–751
(in poultry houses);
Lopes et al. 2007: 29–31
(in poultry houses);
Strümpher and Kalawate 2023: 518
(catalogue of the Oriental and Palearctic species);
Pablo-Cea et al. 2023: 16
(catalogue of
El Salvador
).
Synonyms.
For a comprehensive list, see
Pittino and Bezdĕk (2016: 54–55)
and
Smith (2017: 88)
.
Type specimen examined.Neotype
, here designated
(
♂NHMUK
– Fig.
7
). First label [white, printed]: “
BRASIL
: Rio de Janeiro, / Cabo Frio,
I- 1991
, /
F. Z. Vaz-de-Mello
”. Second label [red, Vinicius Costa-Silva’s handwriting]: “ NEOTYPE /
Trox suberosus
/
Fabricius, 1775
/ des. V. Costa-Silva, 2022 ”. Third label [white with black border, Vinicius Costa-Silva’s handwriting]: “
Omorgus
/
suberosus
/ Det.
V. Costa-Silva
, 2022 ”. Fourth label [white, printed]: “ [QR Code] / WORLD /
TROGIDAE
/ DATABASE / WTD 0000386 ” (Fig.
7 E
).
Type locality
: “ Brasil,
Rio de Janeiro
,
Cabo Frio
”.
Trox suberosusFabricius, 1775
(now
Omorgus suberosus
), Neotype, here designated (♂
NHMUK
):
A.
Habitus in dorsal view;
B.
Habitus in lateral view;
C.
Aedeagus in dorsal view;
D.
Aedeagus in lateral view;
E.
Labels. Scale bars: 1 mm.
Geographic distribution.
Widespread (see below). For details of distribution, see
Huchet and Costa-Silva (2018)
and
Costa-Silva et al. (2021)
.
Neotype
designation of
Trox suberosusFabricius, 1775
.
Trox suberosus
was originally described in 1775 by the Danish entomologist Johan Christian Fabricius (1745–1808) based on an unspecified number of specimens collected from “ Brasilia ” (Latin spelling meaning
Brazil
) that he had examined in the collection of Sir Joseph Banks (“
Mus. Dom. Banks
”). The collection is housed currently in The Natural History Museum, London,
UK
(
Fabricius 1775
;
Zimsen 1964
). Seventy years later,
Erichson (1847)
described the genus
Omorgus
, transferring
Trox suberosus
to the new genus. Even after the proposal of
Erichson (1847)
and the subsequent designation of
Omorgus suberosus
as type species of the genus
Omorgus
by
Lacordaire (1856)
, the species was historically cited as in its original combination by several authors (i. e.,
Harold 1869
;
Harold 1872
;
Burmeister 1876
;
Arrow 1903
;
Bruch 1911
;
Arrow 1912
;
Leng 1920
;
Mutchler 1925
;
Leng 1928
;
Denier 1936
;
Hayward 1936
;
Blackwelder 1944
;
Van Dyke 1953
;
Haaf 1954
;
Vaurie 1955
;
Ritcher 1958
;
Vaurie 1962
;
Zimsen 1964
;
Ritcher 1966
;
Hatch 1971
;
Chalumeau and Gruner 1974
;
Scholtz 1982
). The species remained in the original combination until the systematic study carried out by
Scholtz (1986 a
), where the author proposed
Omorgus
as a genus based on several synapomorphies (see
Scholtz 1986 a
for more details). Scholtz’s proposal (1986 a), which was adopted by recent authors, was supported by the molecular phylogeny conducted by
Strümpher et al. (2014)
.
Omorgus suberosus
is native to the New World and is widely distributed throughout South, Central and North America (from
Canada
to southern
Argentina
) (
Vaurie 1962
;
Scholtz 1990
;
Huchet and Costa-Silva 2018
;
Costa-Silva et al. 2021
). In South America
Omorgus suberosus
is present in all countries except
Chile
(see
Diéguez 2008
). It has also been recorded from the
Galapagos
Archipelago (
Ecuador
) (
Vaurie 1962
;
Scholtz 1990
).
The ubiquitous New World species has also been recorded from other parts of the world (outside of the New World) such as:
Australia
, Europe (from
Belgium
,
Czech Republic
,
Spain
), North Africa (from
Morocco
), Southeast Asia (from the
Philippines
), and on oceanic islands in the Pacific (
Fiji
,
New Caledonia
) and Atlantic (
Cape Verde
, Canary Islands) (
Vaurie 1955
,
1962
;
Scholtz 1986 b
;
Scholtz 1990
;
Batet and López-Colón 1995
;
Páramo 1997
;
Ziani et al. 2015
;
Pittino and Bezdĕk 2016
;
Huchet and Costa-Silva 2018
;
Costa-Silva et al. 2021
). The human hand may have contributed to the dispersal of
Omorgus suberosus
to almost all continents through human migrations, and international transport of products mainly via shipping.
Harold (1872)
mentioned specimens of
Trox suberosus
found in a wool shipment imported from
Argentina
in a factory in Verviers (
Belgium
). With the fast and silent widespread introductions, plus the high degree of intraspecific variability (i. e., colour, size, the shape of elytral tubercles; see
Harold 1872
) of
T. suberosus
(originally described from
Brazil
), a lot of new species names were described for several countries / continents when in fact, they are just morphotypes of the introduced
T. suberosus
. For the list of synonyms, see
Smith (2017)
and
Zidek (2017)
.
Omorgus suberosus
is also known to be highly opportunistic, and in the absence of carcasses will exploit virtually any other source of keratin (or chitin) present in their environment. This species has been recorded feeding on eggs, dung and chicken feathers in poultry farms in
Brazil
(
Gianizella and Prado 1999
;
Lopes et al. 2007
), locust eggs in
Argentina
(Baker 1986), as a “ potential predator ” of the eggs of the turtles in
Mexico
,
Costa Rica
and the Galapagos Islands (
Rosano-Hernández and Deloya 2002
;
Baena et al. 2015
), and iguana eggs also in Galapagos (
Allgower 1979
;
Rosano-Hernández and Deloya 2002
), being considered a risk factor for the survival of these (and other) species considered as vulnerable according to the International Union for the Conservation of Nature (
IUCN
) (see
Baena et al. 2015
).
On the compilation of Fabricius types,
Zimsen (1964)
presented a list mentioning
two type
specimens of
Trox suberosus
: one from Joseph Banks’ collection (housed in the British Museum of Natural History -
NHMUK
) and another from the Zoologisches Museum, Kiel University (
ZMUK
). Both specimens were meticulously studied by us; however, as first noted by
Vaurie (1962)
, the type specimen of
Trox suberosus
lodged in Banks’ collection (
NHMUK
) corresponds to
Trox monachus
(now
Omorgus monachus
– Fig.
8
) described by Johann Friedrich Wilhelm Herbst in 1790, 15 years after
Trox suberosus
description. In the description,
Fabricius (1775)
mentioned “ elytris striatis ” and later “ Elytra minus rugosa […] ”, but none of these statements correspond to the specimen standing as “ type ” of
Trox suberosus
in Banks’ collection. This statement / description of “ elytris striatis ” was repeated in all of Fabricius’ subsequent publications that mentioned
T. suberosus
(
Fabricius 1781
,
1787
,
1792
and 1801; Fig.
9
). According to
Harold (1872)
,
Trox monachus
presents “ tuberculata elytrorum omnia, etiam suturalia, rotundam omnino tomentosa ” and
Vaurie (1962)
presents records of this species only from the
USA
(Florida,
Nebraska
,
Kansas
,
Oklahoma
and
Texas
); the type of
Trox suberosus
is from
Brazil
, probably
Rio de Janeiro
(see
Papavero 1971
). The other specimen mentioned by
Zimsen (1964)
, from
ZMUK
(Fig.
10
), was studied through detailed photographs kindly provided to us by Dr. Michael Kuhlmann (
ZMUK
). With these high-resolution images from various angles, it was possible to confirm, without any doubt, that the specimen from
ZMUK
mentioned as a
Trox suberosus
’
syntype
by
Zimsen (1964)
is a specimen that belongs to the modern concept of the genus
Trox
, and not
Omorgus
. The identification to species level was not conclusive. However, considering that the species described by Fabricius comes from the Banks Collection, there is no reason (or evidence) to consider the specimen housed in
ZMUK
as part of the type series. The label with Fabricius’ handwriting saying “
suberosus
” on the specimen from
ZMUK
was probably put on later and corresponds to either a misidentification of the species or an inadvertent misspelling (between “
sabulosus
” and “
suberosus
”) of a specimen from his own collection.
Supposed
s
yntype of
Trox suberosusFabricius, 1775
(=
Trox monachusHerbst, 1790
) from Joseph Banks collection (
NHMUK
):
A.
Habitus in dorsal view;
B.
Patricia Vaurie’s handwritten note about the type specimen;
C.
Type labels. Scale bar: 1 mm. Photo by Keita Matsumoto (
NHMUK
).
Trox suberosus
’ descriptions provided by Johan Christian Fabricius in his publications of
A.
1775;
B.
1781;
C.
1787;
D.
1792; and
E.
1801.
Alleged
s
yntype of
Trox suberosusFabricius, 1775
(=
Trox
sp.
) from Fabricius collection (
ZMUK
):
A.
Habitus in dorsal view;
B.
Habitus in fronto-lateral view;
C.
Type labels. Photo by Michael Kuhlmann (
ZMUK
).
Since
Vaurie (1962)
, the name-bearing type specimen of
Trox suberosus
(mainly that from
NHMUK
) has been cited as “ problematic ” (i. e.,
Vaurie 1962
;
Hielkema and Hielkema 2019
;
Costa-Silva et al. 2021
), because the specimen does not correspond to the original description. In the case here presented, we believe that all specimens widely recognized and identified as
Trox suberosus
were based on “
common sense
” and on a universally recognized concept, but not based on a proper name-bearing type. As presented here and well-documented in the literature (see
Vaurie 1955
), both
Omorgus suberosus
and
O. monachus
are morphologically well-defined, and universally recognized as different species, and should be treated as such. Due to its non-compliance with the description and the stated type locality, we here propose that the specimen housed in the Banks collection under the name
suberosus
Fabricius is a specimen of the North American
Trox monachus
which has been mistakenly substituted with the original material of
Trox suberosus
from
Brazil
, and that the original type material of
Trox suberosus
has been lost. Such a substitution is particularly credible in the Joseph Banks collection, since the specimens do not have locality labels or determination labels, and the handwritten name labels, and labels indicating ‘ type’, are pinned onto the drawers and not attached to the specimens. Hence a misplaced specimen would not be easy to recognize as such except by comparison with the original description.
In order to establish the single name-bearing type specimen of the widespread
Trox suberosus
, we propose the designation of a
neotype
. Our proposed
neotype
specimen (Fig.
7
) morphologically match with the original description provided by
Fabricius (1775
; Fig.
9 A
) and fulfils the qualifying conditions of ICZN Article 75.3 (
ICZN 1999
). To avoid possible future confusion and to maintain the type locality as consistent as possible, and to comply with ICZN Article 75.3. 6, we here select as the
neotype
a specimen from a similar locality as the presumed lost specimen collected by Joseph Banks during his voyage across the globe on the Endeavour (1768‒1771) (
Zimsen 1964
;
Papavero 1971
). According to
Papavero (1971)
, “ Brasilia, Dom. Banks of Fabricius ” refers to the collection made by Sir. Joseph Banks in Ilha Rasa, off the coast near the Guanabara Bay (Rio de Janeiro) on
December 7
th
, 1768
(for details, see
Banks 1896
; also see Cupello et al. 2023 for additional information about Joseph Bank collection). For detailed diagnoses and redescriptions of
Omorgus suberosus
, see
Harold (1872)
,
Vaurie (1962)
and
Scholtz (1990)
; and for additional high-quality images see also
Huchet and Costa-Silva (2018)
and
Costa-Silva et al. (2021)
.