First records of Sarcophaga (Heteronychia) bulgarica (Enderlein) (Diptera, Sarcophagidae) from Great Britain

Abstract

Dipterists Digest (Second Series) 27: 223-229

Sarcophaga (Heteronychia) bulgarica (Enderlein, 1936) is recorded from Great Britain for the first time, from sites in Bedfordshire, Kent and East Sussex in SE England. The species is compared with the closely related S. (H.) haemorrhoa Meigen, 1826, with which it has possibly been confused in the past, and diagnostic features for their separation are provided. Introduction Approximately 310 species of flesh flies are so far known to occur in Europe (Pape et al. 2015). A relatively small proportion of these (approximately 20%) occur in the British Isles, due to the geographic position and geological history of the islands and to the predominantly thermophilous habits of these flies. A similarly low proportion of species belonging to the subgenus Sarcophaga (Heteronychia Brauer & Bergenstamm, 1889) is known to occur in Great Britain and Ireland, with Chandler (2020a) listing eight out of the 89 species currently considered as valid (Whitmore et al. 2013). Species of Heteronychia whose larval biology is known are predators of terrestrial snails (see Coupland and Barker 2004; Whitmore 2010; Fendane et al. 2018). This biology is recorded in the literature for five of the species occurring in the British Isles, whereas the larval feeding habits of S. (H.) depressifrons Zetterstedt, 1845, S. (H.) pumila Meigen, 1826 and S. (H.) vicina Macquart, 1835 are unknown or unsubstantiated (Whitmore 2010). Here we record, for the first time, a ninth species of Sarcophaga (Heteronychia) from the British Isles, S. (H.) bulgarica (Enderlein, 1936), based on ten male specimens collected in Bedfordshire, Kent and East Sussex, SE England, between 2009 and 2020. We provide characters allowing to distinguish between both sexes of S. (H.) bulgarica and S. (H.) haemorrhoa Meigen, 1826, the British species morphologically most similar to it.

Full text

223
Dipterists Digest 2020 27, 223-229
First records of Sarcophaga (Heteronychia) bulgarica (Enderlein)
(Diptera, Sarcophagidae) from Great Britain
DANIEL WHITMORE, STEPHEN PLUMMER* and LAURENCE
CLEMONS**
Staatliches Museum für Naturkunde Stuttgart, Rosenstein 1, 70191 Stuttgart, Germany;
daniel.whitmore@smns-bw.de
*11 St Margarets Close, Lidlington, Bedfordshire, MK43 0RL, United Kingdom
**14 St. John’s Avenue, Sittingbourne, Kent ME10 4NE, United Kingdom
Summary
Sarcophaga (Heteronychia) bulgarica (Enderlein, 1936) is recorded from Great Britain for the first time, from sites
in Bedfordshire, Kent and East Sussex in SE England. The species is compared with the closely related S. (H.)
haemorrhoa Meigen, 1826, with which it has possibly been confused in the past, and diagnostic features for their
separation are provided.
Introduction
Approximately 310 species of flesh flies are so far known to occur in Europe (Pape et al. 2015).
A relatively small proportion of these (approximately 20%) occur in the British Isles, due to the
geographic position and geological history of the islands and to the predominantly thermophilous
habits of these flies. A similarly low proportion of species belonging to the subgenus Sarcophaga
(Heteronychia Brauer & Bergenstamm, 1889) is known to occur in Great Britain and Ireland,
with Chandler (2020a) listing eight out of the 89 species currently considered as valid (Whitmore
et al. 2013). Species of Heteronychia whose larval biology is known are predators of terrestrial
snails (see Coupland and Barker 2004; Whitmore 2010; Fendane et al. 2018). This biology is
recorded in the literature for five of the species occurring in the British Isles, whereas the larval
feeding habits of S. (H.) depressifrons Zetterstedt, 1845, S. (H.) pumila Meigen, 1826 and S. (H.)
vicina Macquart, 1835 are unknown or unsubstantiated (Whitmore 2010).
Here we record, for the first time, a ninth species of Sarcophaga (Heteronychia) from the
British Isles, S. (H.) bulgarica (Enderlein, 1936), based on ten male specimens collected in
Bedfordshire, Kent and East Sussex, SE England, between 2009 and 2020. We provide characters
allowing to distinguish between both sexes of S. (H.) bulgarica and S. (H.) haemorrhoa Meigen,
1826, the British species morphologically most similar to it.
Methods
Specimens of S. (H.) bulgarica were collected by sweep net, killed in ethyl acetate fumes or in a
freezer and double-mounted on plastazote stages with micropins. The images for Figs 1–2 were
obtained by stacking with an Olympus TG 5 camera in Microscope Mode. The images for Fig. 3
were taken with a Zeiss Axio Zoom.V16 with AxioCam HRc attached (Natural History Museum,
London) and stacked in Helicon Focus version 6.3. Figures 4–7 and 9–12 are reproduced from
Richet et al. (2011) with permission from Pensoft Publishers and were taken by René Richet
(Jaligny-sur-Besbre, France) using an HP Photosmart 912 digital camera attached to an Optica
monocular microscope. Editing of final images and figure plate composition were done in Adobe
Photoshop CS5. Geographic information is listed from the highest administrative level to the
lowest, followed by the OS grid reference. Habitat descriptions are given in square brackets. The
following abbreviations are used: CBC = Chris Bentley private collection, Rye; LCC = Laurence

224
Clemons private collection, Sittingbourne; NHMUK = Natural History Museum, London; SPC =
Stephen Plummer private collection, Lidlington; V.C. = Vice County; WML = World Museum,
Liverpool. The terminology used for external morphology follows Cumming and Wood (2017);
terminology of the male terminalia follows Whitmore et al. (2013).
Fig. 1. Sarcophaga (Heteronychia) bulgarica (Enderlein, 1936), male from Marston Thrift
(SPC).
Records of S. (H.) bulgarica
United Kingdom, England. East Sussex, V.C. 14: 1 male, Rye, Rye Harbour Nature Reserve,
TQ94401878, 15.06.2020, C. Bentley leg. (CBC); 1 male, Rye, Rye Harbour Nature Reserve,
TQ93091936, 17.08.2020, C. Bentley leg. (CBC). East Kent, V.C. 15: 1 male, Whitstable,
Wraik Hill, TR087638, [grassland and scrub], 13.06.2009, L. Clemons leg. (LCC); 1 male, Cherry
Down, Lenham, TQ923524, [chalk grassland], 12.06.2010, L. Clemons leg. (LCC); 1 male, near

225
Faversham, Oare Gunpowder Works Country Park, TR003624, [secondary broadleaved
woodland and marsh], 10.07.2010, L. Clemons leg. (WML); 1 male, Cherry Down, Lenham,
TQ923524, [chalk grassland], 03.08.2010, L. Clemons leg. (LCC); 1 male, Rushenden Marshes,
Queenborough, TQ903711, [pulverised ash infill with brackish pools], 09.07.2012, L. Clemons
leg. (LCC); 1 male, Oare, Brett’s Gravel Workings, TR015625, [woodland adjacent to freshwater
pond], 26.06.2013, L. Clemons leg. (LCC). West Kent, V.C. 16: 1 male, Cuxton, Ranscombe
Farm, TQ704676, [field margin on chalk], 16.08.2016, L. Clemons leg. (LCC). Bedfordshire,
V.C. 30: 1 male, Marston Thrift, SP97154141, 25.04.2020, S. Plummer leg. (NHMUK); 1 male,
Honeydon Roadside Verge Nature Reserve, TL128586, 12.06.2020, S. Plummer leg. (SPC).
Identification
Males of Sarcophaga (Heteronychia) bulgarica (Figs 1, 2, 4, 6) can be distinguished from most
other British and Irish Sarcophaga Meigen, 1826 species by the following combination of
features: thorax with 3 postsutural dorsocentral setae; wing vein R
1
with numerous, closely-set
setulae on dorsal surface; abdominal tergite 3 with a pair of strong median marginal setae;
syntergosternite 7+8 with a large circular patch of grey pruinosity near posterior margin;
epandrium red. With these features, males of S. bulgarica key out in couplet 54 of Whitmore et
al. (2020a) as S. (H.) haemorrhoa. Specimens of S. bulgarica are on average slightly larger than
specimens of S. haemorrhoa (8–12 mm vs 5–11 mm) (Whitmore 2010) and are of a lighter grey
overall appearance, but the following couplet for the terminalia should be used for a certain
identification:
Figs 2–3. Male terminalia: 2, Sarcophaga (Heteronychia) bulgarica (Enderlein, 1936)
(Marston Thrift, SPC); 3, Sarcophaga (Heteronychia) haemorrhoa Meigen, 1826 (England,
NHMUK). A = tip of cercus; B = subapical hump of cercus; C = tip of median process of
juxta; D = tip of lateral process of juxta.
Tip of cercus (Fig. 2, A) gradually tapering from subapical hump of cercus (Fig. 2, B)
and short; median tip of juxta (Figs 2, 4, C) short, not obviously protruding beyond
spoon-like basal processes of juxta (Figs 2, 4, D); tip of juxta narrow in dorsal view,
with two lateral cusps (Fig. 6, E) ................................................................ S. bulgarica
- Tip of cercus (Fig. 3, A) abruptly tapering from subapical hump of cercus (Fig. 3, B)
and long; median tip of juxta (Figs 3, 5, C) long, obviously protruding beyond spoon-
like basal processes of juxta (Figs 3, 5, D); tip of juxta broader in dorsal view, with a
median invagination and without lateral cusps (Fig. 7, F)...................... S. haemorrhoa

226
Figs 4–12. Male and female terminalia [modified from Richet et al. (2011); ©Pensoft
Publishers, reproduced with permission]: 4–5, distiphallus in lateral view; 6–7, distiphallus
in dorsal view; 8, last female abdominal segments in posterior view; 9–10, left half of female
tergite 6; 11–12, spermathecae. 4, 6, 9, 11: Sarcophaga (Heteronychia) bulgarica (Enderlein,
1936) (France). 5, 7, 10, 12: S. (H.) haemorrhoa Meigen, 1826 (France). 8: S. (H.)
haemorrhoa (England, NHMUK). C, E–F = tip of median process of juxta; D = tip of lateral
process of juxta; G = extent of darkening on lateral portion of tergite; H = basal
constriction; * = tergite 6.
Females of S. bulgarica would currently also key out as S. haemorrhoa in couplet 80 of
Whitmore et al. (2020a). Females of these two species can be distinguished from all other British
and Irish Sarcophaga Meigen, 1826 by having 3 postsutural dorsocentral setae, numerous closely-

227
set setulae on the dorsal surface of wing vein R
1
, having a more or less conspicuous mid femoral
organ on the distal posterior surface of the mid femur and having tergite 6 undivided (without a
median pleat) and of a light red/orange colour (Fig. 8). Females of S. bulgarica and S.
haemorrhoa can be primarily distinguished by the extent of the lateral darkening of tergite 6 —
more extensive, reaching innermost spiracle in S. haemorrhoa (Fig. 10); less extensive, not
reaching innermost spiracle in S. bulgarica (Fig. 9) — and by the shape of the spermathecae —
with a clear basal constriction in S. haemorrhoa vs. more evenly shaped in S. bulgarica (Figs 11–
12) (see Richet et al. 2011). The last two characters may show intraspecific variation and their
diagnostic value should be verified across a large number of specimens.
Discussion
With the discovery of S. bulgarica, the British and Irish sarcophagid checklist now stands at 63
published species (see Chandler 2020b). Two further species, one based on recent records and
another based on a single historical record, will be added in a forthcoming paper (Whitmore and
Hall, unpublished), bringing the total to 65. This number is comparable to other northern
European faunas (e.g. Pape 1987); however, it has increased by 12% since Chandler (1998). This
increase may partly be due to a renewed interest in this family in recent years, further boosted by
the launch of a recording scheme (Whitmore et al. 2020b), although the arrival of species from
continental Europe and their establishment in Britain due to favourable changes in climatic
conditions is also possible, as seen with other insect families (e.g. Barclay 2004; Morris and Ball
2004; Chelmick 2012; Chmurova et al. 2018; Salisbury et al. 2018; Siljamo et al. 2020; Raper
2020). Some recently added species may just be very rare or localised or may have been
overlooked due to close similarity with other species. One such example could be Metopia
tshernovae Rohdendorf, 1955, recently discovered by Chandler (2020a). However, other species,
such as Macronychia striginervis (Zetterstedt, 1838), have recently appeared in southern England
and it would seem unlikely for them to have been overlooked in collections (Whitmore and Perry
2018). Sarcophaga bulgarica is a widespread West Palaearctic species which occurs also in
Scandinavia (Pape 1987), so it may just be localised and have been previously overlooked in
Britain, also due to its close resemblance to S. haemorrhoa, a very common and widespread
species in England. On the other hand, the first British records of S. bulgarica presented here are
all relatively recent (post 2008), and our examination of a large number of older specimens of S.
haemorrhoa in the NHMUK and LCC collections, many of which are from SE England, didn’t
reveal any misidentified S. bulgarica. The study of additional historical collections is needed to
accurately assess whether S. bulgarica has recently become established or has long resided in
Britain.
The biology of Sarcophaga bulgarica is currently unknown (see Whitmore 2010). Its
larvae are likely to feed on snails like other Heteronychia species with a known biology, but no
breeding record for this species has yet been published.
Acknowledgements
Thanks to Chris Bentley for allowing us to include his records from Rye Harbour Nature Reserve.
Max Barclay (NHMUK), Galina Jönsson (Imperial College, London), Ian Kitching (NHMUK),
Roger Morris (Mitcham, UK), Ben Price (NHMUK) and Chris Raper (NHMUK) provided
literature on recent species’ arrivals in their groups of interest. Pensoft Publishers gave
permission to use original figures from Richet et al. (2011).

228
References
Barclay, M.V.L. 2004. The green vegetable bug Nezara viridula (L., 1758) (Hem.:
Pentatomidae), new to Britain. Entomologist’s Record and Journal of Variation 116, 55-
58.
Chandler, P.J. 1998. Checklists of Insects of the British Isles (New Series), Part 1: Diptera
(incorporating a list of Irish Diptera). Handbooks for the Identification of British Insects
12, xx + 234 pp. Royal Entomological Society.
Chandler, P.J. 2020a. Metopia tshernovae Rohdendorf (Diptera, Sarcophagidae) an overlooked
British species? Dipterists Digest (Second Series) 27, 100.
Chandler, P.J. 2020b. Checklists of Insects of the British Isles (New Series), Part 1: Diptera
(incorporating a list of Irish Diptera). Handbooks for the Identification of British Insects
12, xx + 234pp. Royal Entomological Society, London. [Version at 1 May 2020,
available at https://www.dipterists.org.uk/checklist.]
Chelmick, D. 2012. Observations of the Willow Emerald Damselfly Lestes viridis (Vander
Linden) in Britain. Atropos 46, 38-42.
Chmurova, L., Mendel, H., Potts, K. and Barclay, M.V.L. 2018. Agapanthia cardui (Linnaeus,
1767) (Cerambycidae: Lamiinae) in Britain, well established in East Kent (VC 15). The
Coleopterist 27(3), 109-113.
Coupland, J.B. and Barker, G.M. 2004. Diptera as predators and parasitoids of terrestrial
gastropods, with emphasis on Phoridae, Calliphoridae, Sarcophagidae, Muscidae and
Fanniidae, pp. 85-158. In Barker, G.M. (Ed.) Natural enemies of terrestrial molluscs.
CABI publishing, Wallingford, Cambridge.
Cumming, J.F. and Wood, D.M. 2017. Adult morphology and terminology. pp. 89-133. In
Kirk-Spriggs, A.H. and Sinclair, B.J. (Eds) Manual of Afrotropical Diptera. Vol. 1.
Suricata 4. South African National Biodiversity Institute Graphics & Editing, Pretoria.
Fendane, Y., Richet, R., Thomann, T., Jourdan, M., Baker, G., Ghamizi, M. and Sheppard, A.
2018. First records of flesh flies (Diptera: Sarcophagidae) emerging from terrestrial
snails in Morocco. African Entomology 26(1), 124-130.
Morris, R.K.A. and Ball, S.G. 2004. Sixty years of Volucella zonaria (Poda) (Diptera:
Syrphidae) in Britain. British Journal of Entomology and Natural History 17, 217-227.
Pape, T. 1987. The Sarcophagidae (Diptera) of Fennoscandia and Denmark. Fauna
Entomologica Scandinavica 19.
Pape, T., Beuk, P., Pont, A.C., Shatalkin, A.I., Ozerov, A.L., Woźnica, A.J., Merz, B.,
Bystrowski, C., Raper, C., Bergström, C., Kehlmaier, C., Clements, D.K., Greathead, D.,
Kameneva, E.P., Nartshuk, E., Petersen, F.T., Weber, G., Bächli, G., Geller-Grimm, F.,
Van de Weyer, G., Tschorsnig, H.-P., de Jong, H., van Zuijlen, J.W., Vaňhara, J.,
Roháček, J., Ziegler, J., Majer, J., Hůrka, K., Holston, K., Rognes, K., Greve-Jensen, L.,
Munari, L., de Meyer, M., Pollet, M., Speight, M.C.D., Ebejer, M.J., Martinez, M.,
Carles-Tolrá, M., Földvári, M., Chvála, M., Barták, M., Evenhuis, N.L., Chandler, P.J.,
Cerretti, P., Meier, R., Rozkošný, R., Prescher, S., Gaimari, S.D., Zatwarnicki, T.,
Zeegers, T., Dikow, T., Korneyev, V.A., Richter, V.A., Michelsen, V., Tanasijtshuk,
V.N., Mathis, W.N., Hubenov, Z. and de Jong, Y. 2015. Fauna Europaea: Diptera –
Brachycera. Biodiversity Data Journal 3, e4187.
Raper, C. 2020. Ectophasia crassipennis (Fabricius) and Phasia aurigera (Egger) (Diptera,
Tachinidae) new to the British fauna in 2019. Dipterists Digest (Second Series) 27, 189-
192.

229
Salisbury, A., Dodd, S., Dunne, N., Mendel, H. and Barclay, M.V.L. 2018. The house longhorn
Hylotrupes bajulus (Linnaeus) (Cerambycidae) outdoors in Britain. The Coleopterist
27(2), 87-90.
Siljamo, P., Ashbrook, K., Comont, R.F. and Skjøth, C.A. 2020. Do atmospheric events explain
the arrival of an invasive ladybird (Harmonia axyridis) in the UK? Plos ONE 15 (1),
e0219335.
Richet, R., Blackith, R.M. and Pape, T. 2011. Sarcophaga of France (Diptera: Sarcophagidae).
pp. 5-327. Pensoft Publishers, Sofia.
Whitmore, D. 2010. Systematics and phylogeny of Sarcophaga (Heteronychia) (Diptera,
Sarcophagidae). Unpublished D. Phil. Thesis, Università la Sapienza, Rome, 257 pp.
[available at https://tinyurl.com/y8rsz3dv]
Whitmore, D., Dupont, S. and Falk, S. 2020a. Key to Adult Flesh Flies (Diptera:
Sarcophagidae) of the British Isles. Version 2. OSF Preprints, July 9.
doi:10.31219/osf.io/vf5r6.
Whitmore, D., Griffiths, C. and Jones, N.P. 2020b. NEW Sarcophagidae Recording Scheme.
Bulletin of the Dipterists Forum 89, 7-10.
Whitmore, D., Pape, T. and Cerretti, P. 2013. Phylogeny of Heteronychia: the largest lineage of
Sarcophaga (Diptera: Sarcophagidae). Zoological Journal of the Linnean Society 169,
604-639.
Whitmore, D. and Perry, I. 2018. Macronychia striginervis (Zetterstedt) new to Britain, and the
misidentification of M. dolini Verves & Khrokalo (Diptera, Sarcophagidae). Dipterists
Digest (Second Series) 25, 91-97.