Print
The first record of Omosita nearctica Kirejtshuk (Coleoptera, Nitidulidae) in South Africa, with the first description of its mature larva
expand article infoKirstin A. Williams§, Crystal-Leigh Clitheroe§|, Martin H. Villet§, John M. Midgley§
‡ KwaZulu-Natal Museum, Pietermaritzburg, South Africa
§ Rhodes University, Makhanda, South Africa
| Okinawa Institute of Science and Technology, Okinawa, Japan
Open Access

Abstract

Sap beetles of the genus Omosita Erichson are stored-product pests that are also associated with carrion, potentially making them biosecurity risks and forensic tools. The discovery of a specimen of the Nearctic species Omosita nearctica Kirejtshuk in South Africa prompted an investigation a decade later to determine if this species had established itself in the country, which was confirmed by the collection of further breeding specimens that also facilitated the first description of mature larvae of O. nearctica. A new key to adults of all Omosita species is presented.

Keywords

Biosecurity, forensic entomology, invasion biology, larval morphology, molecular identification, morphological key

Introduction

Many insects associated with stored products have been moved between continents following humans’ colonisation of new places. In the case of cryptogenic species, this invasion process has been so thorough that the geographical origin of the insect invaders is no longer clear, e.g. the Hide Beetle, Dermestes maculatus DeGeer, 1774 (Coleoptera: Dermestidae) (Mroczkowski 1968). In other cases, these invasive species are not noticed for years even though they may be well-known pests in other countries, e.g. the Oriental Latrine Fly, Chrysomya megacephala (Fabricius, 1794) (Diptera: Calliphoridae) in South Africa (Williams and Villet 2006; Badenhorst and Villet 2018). Insects, and particularly beetles (Midgley et al. 2009), associated with stored animal products, are often of significance in forensic entomology and biosecurity, and keeping track of new members of the carrion insect community in a particular country is important in both of these contexts.

The sap beetle family Nitidulidae has approximately 350 genera and over 4500 species (Lee et al. 2020). The Nitidulidae in Africa have not been well studied and so what is known of them is limited (Kirejtshuk 2001). There are seven recognised species in the genus Omosita Erichson, 1843 – O. discoidea, O. colon, O. depressa, O. funesta, O. smetanai, O. japonica and O. nearctica (Reitter 1873, 1874; Kirejtshuk 1987; Lee et al. 2015). A specimen of O. discoidea in the Naturhistoriska Riksmuseet, Stockholm*, was collected by Gustav de Vylder (Lee et al. 2015), probably during his stays in Cape Town in 1871–1873 and 1879–1885 (de Vylder 1998); no other published records of Omosita in the Afrotropical Region were found.

At least some sap beetles of the genus Omosita are relevant in forensic entomological and biosecurity contexts because they are occasional pests of stored products and can be abundant on carrion and corpses (Hinton 1945; Shubeck et al. 1977; Jelínek 1999; Kočárek 2003; Ewing and Cline 2005; Schlechter 2008; Saloña et al. 2010; Lee et al. 2015; Lyu et al. 2016; Torres et al. 2018; Lee et al. 2020). Several Omosita species have been translocated around the globe, e.g. the Palaearctic species Omosita colon (Linnaeus, 1758) and Omosita discoidea (Fabricius, 1775) have been reported from Australia and New Zealand (Blackburn 1903; Carlton and Leschen 2007); O. colon has been recorded on Pitt Island, 800 km east of New Zealand (Alfken 1904; Emberson 1998); and the Mexican species Omosita funesta Reitter, 1873 is reported from Spain (Audisio 1990). Despite their applied significance and widespread distribution, literature about the distribution of Omosita species is demonstrably scattered.

Omosita nearctica Kirejtshuk, 1987 was described from North America (Kirejtshuk 1987), but nothing has yet been published about its biology. Some North American records of O. colon published or identified before 1987 may actually represent O. nearctica, which was only recognised as a separate species in that year (Kirejtshuk 1987).

The collection of a single specimen of Omosita nearctica in August 2001 in South Africa suggested the introduction of O. nearctica to this country. This paper reports this discovery, confirms the breeding of O. nearctica in South Africa, and provides the first description of its larva.

Materials and methods

Specimen collection

An adult specimen of Omosita nearctica was collected in a trap baited with 50 g of fresh chicken liver in Makhanda (formerly Grahamstown), Eastern Cape province, South Africa, in August 2001, during a study of the seasonal distribution of forensically important flies (Villet et al. 2017; Williams and Villet 2019). The specimen was discovered in 2012 among the ethanol-preserved flies. It was mounted and deposited in the Albany Museum, Makhanda, South Africa (specimen number AM 66416**).

Cooked sheep shank bones were placed in custom-made traps hung about 50 cm above ground in trees at municipal rubbish dumps (or landfills) in Makhanda (33.291°S, 26.492°E) in February 2012 and 2013, and nearby Port Alfred (33.568°S, 26.879°E) in February 2013. The traps were checked regularly and when beetles were caught, they were taken back to Rhodes University and caged with uncooked beef shin bones. Larvae were discovered feeding on the fatty bones in March 2013. The adults (unsexed) and larvae were preserved in 96% ethanol. Five larval specimens were deposited in the wet collection of the KwaZulu-Natal Museum, Pietermaritzburg, South Africa (specimen number NMSA-COL 1405–1409). Adult specimens were card mounted and two specimens were deposited in the KwaZulu-Natal Museum (specimen number NMSA-COL 1898 and NMSA-COL 1410), two in the South African National Collection of Insects, Pretoria, South Africa (accession number SANC-COLG-00021) and two in the Albany Museum, Makhanda, South Africa (specimen numbers AM 101483 and AM 101484).

Identification

The adult beetles (n = 28) were identified from their morphology using the keys in Jelínek (1999) and Lee et al. (2015) and the description and illustrations in Kirejtshuk (1987). A new diagnostic key to the adults of the seven accepted species of Omosita is presented in Appendix 1.

One hind leg of a single beetle (NMSA-COL 1898) was used for DNA analysis. DNA was extracted using the Qiagen DNeasy tissue kit (Qiagen, Inc., Valencia, CA) according to the manufacturer’s instructions. A portion of the cytochrome oxidase I (COI) gene was sequenced using the LCO1490 forward (5'-GGTCAACAAATCATAAAGATATTGG-3') and HCO2198 reverse (5'-TAAACTTCAGGGTGACCAAAAAAT-3') primers. Polymerase chain reaction (PCR) amplification was conducted and the PCR product was sequenced by Macrogen Inc, Seoul, South Korea (https://dna.macrogen-europe.com/). The COI sequence was run through the Basic Local Alignment Search Tool (BLASThttps://blast.ncbi.nlm.nih.gov) to confirm the morphological identification.

To facilitate comparative biology, a molecular phylogeny of four of the seven species of Omosita was estimated. Additional COI sequences of the four widespread Omosita species were downloaded from the Barcode of Life Data System v4 (BOLD) (Table 1) and analysed together with the new sequence. Brachypeplus glaber LeConte (Nitidulidae: Cillaeinae) and two species of Nitidula Fabricius (Nitidulidae: Nitidulinae) were used as outgroups. Bayesian inference analyses were performed with MrBayes (Huelsenbeck and Ronquist 2001) using the best-fitting nucleotide substitution mode (GTR+G) from jModelTest (Posada 2008). One cold and three hot chains were run for 5 000 000 generations, sampling every 1 000 generations with burn-in of 1 000 samples (20%).

Table 1.

Sequences from NCBI GenBank and BOLD used in the Bayesian inference analysis. New sequences are set in bold typeface.

Species Location GenBank accession number BOLD Sequence ID
Omosita colon Athenstedt, Germany KU907100 GCOL10982-16.COI-5P
Athenstedt, Germany KU910800 GCOL10988-16.COI-5P
Edenkoben-Rhodt, Villa Ludwigshoehe, Germany KM441201 FBCOO036-13.COI-5P
Haembach, Haembacher Teich, Halde, Germany KU913847 GCOL5018-16.COI-5P
Hailiniemi, Finland KJ965999 COLFE1417-13.COI-5P
Hailiniemi, Finland KJ966608 COLFE1416-13.COI-5P
Kallvik, Helsinki, Finland KJ965633 COLFD167-12.COI-5P
Kallvik, Helsinki, Finland KJ967401 COLFD168-12.COI-5P
Lauttasaari, Finland KJ965605 COLFE421-12.COI-5P
Nobitz-Klausa, Leinawald, Germany KM446224 GBCOL020-12.COI-5P
Wesel-Diersfordt, Diersfordter Wald Gatter, Germany KM452483 FBCOC604-10.COI-5P
Omosita depressa Arnsberg-Breitenbruch, NWZ Hellerberg, Germany KM442498 FBCOH678-12.COI-5P
Bornheim-Hemmerich, Ortslage, Germany KM446940 FBCOG1013-12.COI-5P
Nobitz-Klausa, Leinawald, Germany KM449233 GBCOC743-12.COI-5P
Oberheimbach, Franzosenkopf, Germany KM439454 GBCOE444-13.COI-5P
Omosita discoidea Bornheim-Hemmerich, Ortslage, Germany KU919455 GCOL7562-16.COI-5P
Langenthal, Germany KU912774 GCOL9483-16.COI-5P
Rowe Tamarack Trail, Canada KM849291 SSWLC101-13.COI-5P
Saalealtarm, Germany KU909461 GCOL9547-16.COI-5P
Schaidt, NWR Stuttpferch, Germany KM445991 FBCOE490-12.COI-5P
Staerkerwald, Germany KU916825 GCOL7701-16.COI-5P
Wandersleben, Burg Gleichen, Germany KU919608 GCOL9399-16.COI-5P
Omosita nearctica Charitable Research Reserve, Canada MG054067 RRSSC3383-15.COI-5P
Omosita nearctica Makhanda (previously Grahamstown), South Africa MT371766
Omosita nearctica a Puslinch, Canada MG058703 COLON045-10.COI-5P
Omosita nearctica Sable Island National Park Reserve, Canada KR916043 CNSIB573-15.COI-5P
Omosita sp. Kawartha Lakes, Canada BARSL067-16.COI-5P
Outgroups
Brachypeplus glaber United States of America KC491232 GBCL15295-13.COI-5P
Nitidula bipunctata Rana u Loun, Oblik, Czech Republic KM452114 GBCOU1431-13.COI-5P
Langenthal, Germany KU909854 GCOL9484-16.COI-5P
Wandersleben, Burg Gleichen, Germany KU908969 GCOL9400-16.COI-5P
KU918404 GCOL9401-16.COI-5P
Nitidula rufipes Hailiniemi, Finland KJ962313 COLFE1409-13.COI-5P
KJ965428 COLFE1410-13.COI-5P
KJ963473 COLFE1411-13.COI-5P
KJ964776 COLFE1412-13.COI-5P
Rana u Loun, Oblik, Czech Republic KM440272 GBCOU1469-13.COI-5P
KM443376 GBCOU1470-13.COI-5P
KM441409 GBCOU1861-13.COI-5P
KU915079 GCOL6778-16.COI-5P

Larval morphology

Three mature larvae were prepared for scanning electron microscopy (SEM) by critical-point drying and sputter-coating with gold (NMSA-COL 1402). The specimens were viewed with a Zeiss Evo LS 15 SEM at the University of KwaZulu-Natal’s Microscopy and Microanalysis Unit, Pietermaritzburg, South Africa. Two mature larvae were slide mounted using standard protocols and viewed using a Leica compound microscope (NMSA-COL 1403 and 1404). A further five mature larvae were examined using a Leica dissecting microscope (NMSA-COL 1405–1409). Measurements were taken using a graduated eye-piece.

Results

Morphological identification

Twenty-eight adult specimens of Omosita were collected in Makhanda (1 in 2001, 12 in February 2012 and 15 in February 2013) but none in Port Alfred. The beetles keyed out as Omosita colon using the keys to Palaearctic species of Omosita presented by Jelínek (1999) and Lee et al. (2015), but these keys necessarily do not include O. nearctica, which is as yet unknown from the Palaearctic. Kirejtshuk (1987) compared his newly described O. nearctica with O. colon and his description and figures confirmed that our specimens were O. nearctica.

Molecular identification

The partial COI sequence from one specimen (Genbank accession number: MT371766, NMSA-COL 1898) was 656 bp long and aligned easily with the other sequences. It had a 100% BLAST match to O. nearctica, with the highest match to O. colon at 89.31% (Table 2). In the Bayesian inference tree (Fig. 2), the new sequence forms a clade exclusively containing other O. nearctica sequences.

Table 2.

BLAST metrics of similarity for Omosita nearctica sequence from Makhanda, South Africa.

Species % Coverage % Match E-value
Omosita nearctica 100% 100% 0.0
Omosita colon 99% 89.3% 0.0
Omosita discoidea 99% 88.21% 0.0
Omosita depressa No significant similarity
Nitidula rufipes 100% 87.82% 0.0
Nitidula bipunctata No significant similarity

Taxonomy

Diagnosis of adult

Body length 2.4–3.7 mm, oblong ovate, sparsely pubescent, testaceous except for piceous markings on anterior half of elytra, and pale markings on lateral pronotal margins and posterior half of elytra; antennal club not longer than wide; pronotum transverse, concave anteriorly and arcuate laterally, with sides converging more apically than basally, with two oval depressions before scutellum; elytra jointly at least 0.75 as wide as their length, their apices obliquely rounded, forming a common arc and usually exposing one abdominal tergite (Fig. 1). The phallobase is subparallel, with the parameres fused and not divergent; the tegmen is anteriorly transverse and shallowly excavate apically.

Figure 1. 

Omosita nearctica adult, dorsal and ventral view, captured in February 2013 in Makhanda, South Africa. Scale bar: 0.5 mm.

Omosita colon differs most notably from O. nearctica in the shape of the antennal club which is elongate-oval, much longer than wide and its body shape which is oval. Omosita discoidea differs from O. nearctica in the pronotum colour which is black in the centre and testaceous towards the edges and the antennal club which is longer than wide (Kirejtshuk 1987; Lee et al. 2015)

Figure 2. 

Bayesian inference tree of COI sequences. Posterior probability values are shown on branches. Red text is the South African sequence generated in this study.

Description of mature larva

Measurements. Body length 4 mm. Head capsule 0.5 mm wide.

Body (Fig. 3). Body campodeiform; subdepressed; widest in abdominal region; white or yellow; uniformly pigmented; poorly sclerotised. Head and all terga with scattered setae; body setae with apices entire.

Figure 3. 

Omosita nearctica larva – dorsal (L) and ventral (R) views. hc = head capsule m = mesothorax, mt = metathorax, p = prothorax, pu = pregomphus, sp = spiracle, st = stemmata, u = urogomphus, 1–9 = abdominal tergites. Scale bar: 0.5 mm.

Head (Figs 4–6). Head capsule (Fig. 4) 2.3 times as wide as long (excluding the labrum); trapezoidal, tapered towards mouthparts; lateral margins straight, at most gently convex; dorsal hind margin slightly retracted; ventral hind margin strongly retracted; granular or tuberculate; with one dorsal and no ventral stemma on each side. Antenna with three antennomeres. Basal antennomere almost as long as wide; without setae. Second antennomere as long as or slightly longer than first; with mesal, subapical sensory area bearing a large cone; with sensory appendix about two thirds the length of third antennomere; with setae, including one directly proximal to sensory area. Third antennomere about as long as basal antennomere; setose with a group of minute apical setae. Frontal sutures impressed, reaching near antennal insertions; frontoclypeal suture distinct laterally, obsolete medially. Clypeus trapezoidal; with three pairs of submarginal setae; clypeal protuberances weak. Clypeolabral suture nearly straight.

Mandible (Fig. 5) apex bidentate; with two subequal lateroventral setae. Prostheca consists of several large lobes; bearing a lightly sclerotized projection at base. Mola transversely ridged. Maxilla elongated. Maxillary palp three-segmented; with third joint longer than first or second. Galea with large, dense apical brush. Lacinia partially fused to galea. Mala enlarged inner-distally; bearing rather sparsely scattered microtrichia. Labium about 1.5 times as long as wide. Labial palp one-segmented; set close at base of labium. Ligula strongly produced. Mentum indistinctly separated from submentum. Submentum with two pairs of setae, one proximal and one distal (Fig. 6).

Figures 4–6. 

4 SEM dorsal view of head capsule and thorax of Omosita nearctica larva. ant = antenna, cly = clypeus, hc = head capsule, m = mesothorax, mt = metathorax, p = prothorax 5 SEM ventral view of left mandible of Omosita nearctica larva. mo = mola, pc = prostheca 6 SEM ventral view of head of Omosita nearctica larva. ant = antenna, la = labrum, lp = labial palp, mb = mandible, mn = mentum, mx = maxilla, mxp = maxillary palp, sm = submentum. Scale bars: 500 μm (4), 20 μm (5, 6).

Thorax (Figs 4, 7). Thoracic tergites (Fig. 4) partially spanning dorsum; medially divided into paratergites. Meso- and metathoracic paraterga small; transversely rectangular; weakly rugose; slightly raised and set close together on mesothorax and touching on metathorax.

Legs (Fig. 7). Femur 1.5 times longer than wide. Tibia twice as long as wide. Tarsungulus slightly longer than half of tibia; moderately, evenly curved. Forelegs slightly shorter than other legs.

Abdomen (Figs 3, 8, 9). Abdomen about three times as long as thorax (Fig. 3). Abdominal tergites T1-T8 about one fourth as wide as body; medially divided into paratergites. Abdominal paratergites transversely rectangular, weakly rugose, slightly raised, and touching. Pregomphi on ninth tergite, small. Urogomphi (Fig. 8) on ninth tergite unsegmented, half the length of ninth tergum; (viewed dorsally) parallel; (viewed laterally) gradually recurved anteriorly (Fig. 9a). Abdominal spiracles exposed; in posterolateral angles of segment. Spiracular tubes present, longer on segments A7 and, particularly, A8; on A8, as wide as tall. Abdominal sternites unsclerotised; intersternal membranes with shagreened patch along anterior margin.

Figures 7, 8. 

7 SEM of hind leg of Omosita nearctica larva. co = coxa, fe = femur, ti = tibia, tr = tarsungulus 8 SEM dorsal view of final segments of the abdomen of Omosita nearctica larva. pu = pregomphus, sp = spiracle, u = urogomphus, 6–9 = abdominal tergites. Scale bars: 100 μm (7), 200 μm (8).

Figure 9. 

Lateral view of terminal end of Omosita nearctica (a) and O. colon (b). pu = pregomphus, u = urogomphus. Not to same scale.

Discussion

This study presents the first record of Omosita nearctica in South Africa and confirms that it is established as a self-sustaining, breeding alien invasive species in the Eastern Cape Province of South Africa. The COI gene (Fig. 2) agreed with the morphological identification of the beetles as O. nearctica. The sequence from this study grouped together in a clade with three other sequences of O. nearctica that were separated from its sister clade, O. colon, with 100% posterior probability (Fig. 2). One sequence (BOLD Public Record COLON045-10.COI-5P) identified as O. nearctica grouped unambiguously with the O. discoidea clade.

The morphological character states listed in Table 3 may be used to differentiate the mature larva of O. nearctica from that of O. colon, the only other species of Omosita for which the larva has been described (Eichelbaum 1903; Verhoeff 1923; Hinton 1945; Böving and Rozen 1962; Hayashi 1978; Díaz-Aranda et al. 2018). The description of the urogomphi of O. colon by Hayashi (1978) differs from the description by Díaz-Aranda et al. (2018). Hayashi (1978) describes them as short and Díaz-Aranda et al. (2018) states they are half the length of the ninth tergite which appears to be more accurate (Fig. 9b). It must be noted that the pregomphi and urogomphi are all referred to as urogomphi by Díaz-Aranda et al. (2018). It is crucial to recognise that because O. nearctica was recognised only in 1987, prior references to O. colon larvae from the Nearctic (e.g. Hinton 1945; Böving and Rozen 1962) may be in error.

Table 3.

Character states differentiating the known larvae of Omosita species. The character states for O. colon were derived from consideration of descriptions by Eichelbaum (1903), Verhoeff (1923), Hayashi (1978), Díaz-Aranda et al. (2018). North American descriptions of larvae of O. colon that predate the description of O. nearctica (Hinton 1945; Böving and Rozen 1962; Díaz-Aranda et al. 2018) were not used because they may involve unwitting misidentifications.

Character Character state
Omosita nearctica Omosita colon
Head capsule 2.3 times as wide as long (excluding labrum) 1.4 times as wide as long (excluding labrum)
2nd antennomere with setae, including one directly proximal to sensory area without setae
Sensory appendix of 2nd antennomere about two thirds as long as 3rd antennomere about half as long as 3rd antennomere
Mola transversely ridged transversely ridged and asperated
Abdominal paratergites touching in midline set fairly close together but not touching in midline
Spiracular tubes on A8 as wide as tall wider than tall

The collection of adults in Makhanda in 2001, 2012 and 2013 confirmed that O. nearctica has probably established in South Africa. This is important in the global context of this species as it has apparently never been recorded outside North America (GBIF.org 2020). The small size, furtive habits and internationally traded diets of sap beetles in general make them good candidates for transport around the world. For instance, at least 32 extralimital species have established in Europe (Jelínek et al. 2016). Most of these species feed on ripening and decaying fruit, but O. funesta was imported from Mexico to Teruel, Spain in 1931, “probably on imported sausages” (Jelínek et al. 2016). Species of Omosita are generally associated with human middens and animal remains (Hinton 1945; Shubeck et al. 1977; Jelínek 1999; Kočárek 2003; Ewing and Cline 2005; Schlechter 2008; Saloña et al. 2010; Lee et al. 2015; Lyu et al. 2016; Torres et al. 2018), so it is less obvious how they were transported to Africa. Omosita nearctica was probably introduced to South Africa on stored products imported through a port or airport. Given the age and remoteness of some austral introductions of Omosita (Blackburn 1903; Alfken 1904; Jelínek et al. 2016), it is possible that the population established well before it was discovered.

Their presence in Makhanda (E. Cape, RSA) suggests that they have been in South Africa for many years, since the town has no international airport and the nearest commercial harbours are over 120 km away. The failure to find specimens in Port Alfred (E. Cape, RSA) is ambiguous evidence of the species’ distribution because the sampling effort was limited.

Nothing is published about the biology of O. nearctica (Kirejtshuk, 1987). That O. nearctica larvae feed on cooked sheep bones suggests that this species feeds on saponified oils and decomposing material, like at least some other species in its genus (Lee et al. 2015; Lyu et al. 2016). In China, O. colon was the only species of beetle observed breaking down adipocere on corpses, potentially giving that species specific significance in medico-criminal forensic entomology (Lyu et al. 2016). The similar diets and close relationship (Fig. 2) of O. colon and O. nearctica imply that the latter species may be similarly useful (Midgley et al. 2009). Beetles associated with stored animal products are often relevant to biosecurity. Further studies on the biology of this species should monitor its global spread and determine its usefulness in forensic entomology. The description of the mature larva will assist in identifying this species where only larvae are found associated with stored products, corpses or carcasses.

Acknowledgements

We thank Lyndall Pereira for assistance with DNA extraction and amplification; Burgert Muller for assistance with editing of graphics; Gimo Daniel, Alexander Kirejtshuk, Burgert Muller, one anonymous reviewer and especially Riaan Stals for their valuable comments; and the National Research Foundation (NRF) of South Africa for funding. Any opinion, findings and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Research Foundation. Omosita nearctica is neither CITES-listed nor endangered according to regional Red Lists or South Africa’s Threatened or Protected Species (ToPS) legislation and thus did not require special sampling permission.

References

  • Alfken JD (1904) Beitrag zur Insektenfauna der Hawaiischen und Neuseeländischen Inseln (Ergebnisse einer Reise nach dem Pacific, Schauinsland 1896–97). Zoologische Jahrbucher. Abteilung fur Systematik, Geographie und Biologie der Tiere 19: 561–628. [Contribution to the Insect fauna of the Hawaiian Islands and New Zealand, results of a journey to the Pacific, Schauinsland.]
  • Audisio PA (1990) Notas sobre Nitidulidae ibero-marroquies (Col.). Eos (Madrid) 66: 25–27. [Notes on Iberian and Moroccan Nitidulidae (Col).]
  • Blackburn T (1903) Further notes on Australian Coleoptera, with descriptions of new genera and species, xxxiii. Transactions and Proceedings and Report of the Royal Society of South Australia 27: 261–309.
  • Böving A, Rozen J (1962) Anatomical and systematic study of the mature larvae of the Nitidulidae (Coleoptera). Ent. Medd. , Copenhagen 31: 265–299.
  • Carlton C, Leschen A (2007) Descriptions of Soronia complex (Nitidulidae: Nitidulinae) larvae of New Zealand with comments on life history and taxonomy. New Zealand Entomologist 30(1): 41–51. https://doi.org/10.1080/00779962.2007.9722150
  • de Vylder G (1998) The journal of Gustav de Vylder, naturalist in South-West Africa (translated by I. & J. Rudner). Van Riebeeck Society 28.
  • Díaz-Aranda LM, Martín-Vega D, Baz A, Cifrián B (2018) Larval identification key to necrophagous Coleoptera of medico-legal importance in the western Palaearctic. International Journal of Legal Medicine 132(6): 1795–1804. https://doi.org/10.1007/s00414-018-1909-2
  • Eichelbaum F (1903) Larve und Puppe von Omosita colon L. Allgemeine Zeitschrift für Entomologie 8: 81–87.
  • Ewing CP, Cline AR (2005) Key to adventive sap beetles (Coleoptera: Nitidulidae) in Hawaii, with notes on records and habits. Coleopterists Bulletin 59(2): 167–183. https://doi.org/10.1649/736
  • Hayashi N (1978) A contribution to the knowledge of the larvae of Nitidulidae occurring in Japan (Coleoptera : Cucujoidea). Insecta Matsumurana 14: 1–97. [New Series]
  • Hinton HE (1945) A monograph of the beetles associated with stored products (Vol. I). British Museum (Natural History), London, 443 pp.
  • Jelínek J (1999) Contribution to taxonomy of the beetle subfamily Nitidulinae (Coleoptera: Nitidulidae). Folia Heyrovskyana 7: 251–281.
  • Jelínek J, Audisio P, Hájek J, Baviera C, Moncoutier B, Barnouin T, Brustel H, Genç H, Leschen RAB (2016) Epuraea imperialis (Reitter, 1877). New invasive species of Nitidulidae (Coleoptera) in Europe, with a checklist of sap beetles introduced to Europe and Mediterranean areas. Atti della Accademia Peloritana dei Pericolanti, Classe di Scienze Fisiche, Matematiche e Naturali 94: A4-1-A4-24. https://doi.org/10.1478/AAPP.942A4
  • Kirejtshuk AG (1987) Новые таксоны жуков-блестянок (Coleoptera, Nitidulidae) Восточного полушария (часть 1). Omosita nearctica sp.n., викарирующий с палеарктическим O. colon (L.). Труды Зоологического института АН СССР 164: 63–94.[New taxa of the sap beetles (Coleoptera, Nitidulidae) of the East Hemisphere Part 1. Omosita nearctica sp. n., vicariant of Palaearctic O. colon (L). Proceedings of the Zoological Institute Academy of Sciences of the USSR]
  • Kirejtshuk AG (2001) Notes on the systematics of the African Nitidulidae (Coleoptera). Annales Historico-Naturales Musei Nationalis Hungarici 93: 17–89.
  • Lee S, Kirejtshuk A, Lee S (2015) Review of the genus Omosita Erichson (Coleoptera: Nitidulidae: Nitidulinae) in Korean fauna, with key to the Palaearctic species. Journal of Asia-Pacific Entomology 18(4): 837–834. https://doi.org/10.1016/j.aspen.2015.10.009
  • Lee MH, Lee S, Leschen RAB, Lee S (2020) Evolution of feeding habits of sap beetles (Coleoptera: Nitidulidae) and placement of Calonecrinae. Systematic Entomology 45: 911–923. https://doi.org/10.1111/syen.12441
  • Lyu Z, Wan L, Yang Y, Tang R, Xu L (2016) A checklist of beetles (Insecta, Coleoptera) on pig carcasses in the suburban area of southwestern China: A preliminary study and its forensic relevance. Journal of Forensic and Legal Medicine 41: 42–48. https://doi.org/10.1016/j.jflm.2016.04.009
  • Midgley JM, Richards CS, Villet MH (2009) The Utility of Coleoptera in Forensic Investigations. In: Amendt J, Campobasso CP, Goff ML, Grassberger M (Eds) Current Concepts in Forensic Entomology. Springer Netherlands, Dordrecht, 57–68. https://doi.org/10.1007/978-1-4020-9684-6_4
  • Mroczkowski M (1968) Distribution of the Dermestidae (Coleoptera) of the world with a catalogue of all known species. Annales Zoologici Warszawa 26: 15–191.
  • Reitter E (1873) Systematische Eintheilung der Nitidularein. Verhandlungen des naturforschenden Vereines in Brünn 12: 4–194.
  • Reitter E (1874) Beschreibungen neuer Käfer-Arten nebst synonymischen Notizen. Zool.-Bot. Ges. Österreich 24: 509–528.
  • Saloña MI, Moraza ML, Carles-Tolrá M, Iraola V, Bahillo P, Yélamos T, Outerelo R, Alcaraz R (2010) Searching the soil: forensic importance of edaphic fauna after the removal of a corpse. Journal of Forensic Sciences 55(6): 1652–1655. https://doi.org/10.1111/j.1556-4029.2010.01506.x
  • Schlechter J (2008) Beetle fauna found on carrion in three woodland sites in Luxembourg (Insecta, Coleoptera). Bulletin de la Societe des Naturalistes Luxembourgeois 109: 97–100.
  • Shubeck PP, Downie NM, Wenzel RL (1977) Species composition of carrion beetles in a mixed-oak forest. Memorial Forest Bulletin 1975: 12–17.
  • Torres HH, Martínez OG, García IS, Uribe LAA, Peña RSR (2018) Primer registro de Omosita colon (Linnaeus) (Coleoptera: Nitidulidae: Nitidulinae) recolectada en cadáveres de cabrito (Capra aegagrus hircus Linnaeus) en Buenavista, Saltillo Coahuila, México. Insecta Mundi 0626: 1–5.
  • Verhoeff KW (1923) Beitrage zur Kenntnis der Coleopteren-Larven mit besonderer Beriicksichtigung der Clavicornia. Arch. Natg. Berlin Abt 89: 1–109.
  • Villet MH, Clitheroe C, Williams KA (2017) The temporal occurrence of flesh flies (Diptera, Sarcophagidae) at carrion-baited traps in Grahamstown, South Africa. African Invertebrates 58(1): 1–8. https://doi.org/10.3897/AfrInvertebr.58.9537
  • Williams KA, Villet MH (2006) A new and earlier record of Chrysomya megacephala in South Africa, with notes on another exotic species, Calliphora vicina (Diptera: Calliphoridae). African Invertebrates 47: 347–350.
  • Williams KA, Villet MH (2019) Spatial and seasonal distribution of forensically important blow flies (Diptera: Calliphoridae) in Makhanda, Eastern Cape, South Africa. Journal of Medical Entomology 1–8. https://doi.org/10.1093/jme/tjz056

Appendix 1

Key to adults of the species of the genus Omosita (based on diagnostic character states proposed by Reitter 1873, 1874; Kirejtshuk 1987; Jelínek 1999 and Lee et al 2015).

1 Pronotum with convex median area not demarcated from explanate lateral margins by grooves 2
Pronotum with convex median area demarcated from explanate lateral margins by roughly parallel, arcuate grooves 5
2(1) Antennal club elongate-oval, distinctly longer than wide 3
Antennal club rounded or subtriangular, not longer than wide 4
3(2) Elytra 1.5 times longer than their combined width. Pronotum narrowly explanate laterally; anterior margin shallowly, arcuately notched. Antennal club not constricted in middle Omosita funesta
Elytra at most 1.3 times longer than their combined width. Pronotum widely explanate laterally; anterior margin deeply notched; Antennal club constricted in middle Omosita discoidea
4(2) Antennal club rounded, about as long as wide. Mentum without distinct sulcus along posterior border Omosita nearctica
Antennal club broad or subquadrangular to obovate to trapezoidal or subtriangular, usually shorter than wide. Mentum with distinct transverse sulcus along posterior border Omosita japonica
5(1) Grooves between convex median area of pronotum and its explanate margins indistinct Omosita colon
Grooves between convex median area of pronotum and its explanate margins distinct 6
6(5) Pronotum narrowly explanate laterally. Antennal club not constricted in middle. Postmentum with lateral margins raised and sharp; its punctation rugose Omosita smetanai
Pronotum widely explanate laterally. Antennal club constricted in middle. Postmentum with lateral edges margins; its punctation simple and widely spaced Omosita depressa

1 The report of a specimen in the Natural History Museum, London (Lee et al. 2015) is a lapsus calami (Kirejtshuk, pers. comm.).
2 This specimen is misidentified on the Global Biodiversity Information Facility (GBIF) as Omosita japonica (Gess and Ranwashe 2017).