Research Article |
Corresponding author: Kirstin Williams ( kwilliams@nmsa.org.za ) Academic editor: Pierfilippo Cerretti
© 2016 Kirstin Williams, Martin Villet, Jennifer Lamb.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Williams KA, Lamb J, Villet MH (2016) Phylogenetic radiation of the greenbottle flies (Diptera, Calliphoridae, Luciliinae). ZooKeys 568: 59-86. https://doi.org/10.3897/zookeys.568.6696
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The subfamily Luciliinae is diverse and geographically widespread. Its four currently recognised genera (Dyscritomyia Grimshaw, 1901, Hemipyrellia Townsend, 1918, Hypopygiopsis Townsend 1916 and Lucilia Robineau-Desvoidy, 1830) contain species that range from saprophages to obligate parasites, but their pattern of phylogenetic diversification is unclear. The 28S rRNA, COI and Period genes of 14 species of Lucilia and Hemipyrellia were partially sequenced and analysed together with sequences of 11 further species from public databases. The molecular data confirmed molecular paraphyly in three species-pairs in Lucilia that hamper barcode identifications of those six species. Lucilia sericata and L. cuprina were confirmed as mutual sister species. The placements of Dyscritomyia and Hypopygiopsis were ambiguous, since both made Lucilia paraphyletic in some analyses. Recognising Hemipyrellia as a genus consistently left Lucilia s.l. paraphyletic, and the occasionally-recognised (sub)genus Phaenicia was consistently paraphyletic, so these taxa should be synonymised with Lucilia to maintain monophyly. Analysis of a matrix of 14 morphological characters scored for adults of all genera and for most of the species included in the molecular analysis confirmed several of these findings. The different degrees of parasitism were phylogenetically clustered within this genus but did not form a graded series of evolutionary stages, and there was no particular relationship between feeding habits and biogeography. Because of the ubiquity of hybridization, introgression and incomplete lineage sorting in blow flies, we recommend that using a combination of mitochondrial and nuclear markers should be a procedural standard for medico-criminal forensic identifications of insects.
Lucilia sericata , Lucilia cuprina , molecular systematics, parasitism, myiasis
All four genera of the subfamily Luciliinae are reported to exhibit parasitism in the form of myiasis – the infestation of humans’ and other animals’ living tissues by fly larvae (
At the highest taxonomic level,
Several other genera have been included in the Luciliinae, such as Bufolucilia Townsend, 1919, Francilia Shannon, 1924, Acrophagella Ringdahl, 1942, Phumonesia Villeneuve, 1914 and Viridinsula Shannon, 1926 but most of these are now treated as synonyms of Lucilia. Lucilia itself has been variously divided into subgenera (
The largest genus in the subfamily, Lucilia has received few quantitative phylogenetic studies (
At the species level, L. sericata and L. cuprina have been referred to as sister-species (Ash and Greenberg 1974) because they are very similar morphologically and each is often misidentified as the other. They are now both found in Australia, New Zealand, South Africa, large parts of Asia, Europe and North America (
Several studies have established that natural hybrids of L. sericata and L. cuprina exist (
The aims of this study are therefore to confirm if L. sericata and L. cuprina are sister-species; to explore if L. coeruleiviridis (Macquart, 1855) / L. mexicana Macquart, 1843 and L. caesar (Linnaeus, 1758) / L. illustris (Meigen, 1826) are paraphyletic species; to examine the relationships between the species of Lucilia and clarify the taxonomic status of Phaenicia; to estimate the relationships of Dyscritomyia, Hemipyrellia, Hypopygiopsis and Lucilia; and to assess the geographical and phylogenetic patterns of myiasis-causing behaviour in these flies.
Adult Lucilia flies were obtained from around the world (Table
Specimen locality data for sequences added to GenBank. (Accession numbers starting KF are new sequences from this study).
Species | Specimen | Locality | Accession Number | |||
---|---|---|---|---|---|---|
28S | Per | COI | ||||
Calliphora vicina | CV_FRC_01(F) | Montferrier-Sur-Lez | France | JN792781 | KF839531 | KF839562 |
CV_FRC_02(M) | Montferrier-Sur-Lez | France | KF839506 | |||
Hemipyrellia fernandica | H_BEN_01(M) | Contonou | Benin | KF839511 | KF839539 | KF839567 |
H_BEN_02(M) | Contonou | Benin | KF839512 | KF839540 | KF839568 | |
H_SA_DBN_01(F) | Durban | South Africa | KF839513 | KF839541 | KF839569 | |
H_TAN_01(M) | Mkuraja | Tanzania | KF839514 | KF839542 | KF839570 | |
H_TAN_02(M) | Mkuraja | Tanzania | KF839515 | KF839543 | KF839571 | |
Lucilia caesar | Ca_FRC_01(M) | Montferrier-Sur-Lez | France | JN792782 | JN792858 | KF839556 |
Ca_FRC_02(F) | Montferrier-Surz-Lez | France | KF839501 | KF839532 | KF839557 | |
Lucilia coeruleiviridis | Co_CAN_01(M) | Windsor | Canada | KF839502 | KF839533 | KF839558 |
Co_CAN_02(M) | Windsor | Canada | KF839503 | KF839559 | ||
Co_USA_03(F) | Putnam Co. Missouri | United States of America | KF839504 | KF839534 | KF839560 | |
Co_USA_04(F) | Martinstown, Missouri | United States of America | KF839505 | KF839561 | ||
Lucilia cuprina | C_AUS_01 (M) | Sydney | Australia | KF856254 | JN792622 | |
C_EGT_01 (F) | Alexandria | Egypt | JN792706 | JN792784 | JN792625 | |
C_SA_CT_02 (F) | Cape Town | South Africa | JN792713 | JN792791 | JN792632 | |
C_SA_DBN_01(F) | Durban | South Africa | JN792724 | JN792802 | JN792642 | |
C_THA_02 (F) | Chiang Mai | Thailand | JN792741 | JN792819 | JN792661 | |
C_THA_03 (F) | Chiang Mai | Thailand | JN792742 | JN792820 | JN792662 | |
C_ZIM_02 (F) | Matobos | Zimbabwe | JN792745 | JN792823 | JN792667 | |
Lucilia eximia | Ex_CSR_01(F) | Santo Domingo | Costa Rica | KF839507 | KF839535 | KF839563 |
Ex_CSR_02(F) | Santo Domingo | Costa Rica | KF839508 | KF839536 | KF839564 | |
Lucilia fayeae | Fa_DOM_01(F) | Calibishie | Dominica | KF839509 | KF839537 | KF839565 |
Fa_DOM_02(F) | Calibishie | Dominica | KF839510 | KF839538 | KF839566 | |
Lucilia illustris | IL_CAN_01(F) | Windsor | Canada | KF839516 | KF839544 | KF839572 |
IL_CAN_02(F) | Windsor | Canada | KF839517 | KF839545 | KF839573 | |
IL_JPN_01(F) | Iwate Medical University | Japan | KF839518 | KF839546 | KF839574 | |
IL_JPN_02(F) | Iwate Medical University | Japan | KF839519 | KF839547 | KF839575 | |
IL_SWZ_01(F) | Lausanne-Suisse | Switzerland | KF839520 | KF839548 | ||
IL_USA_01(F) | Michigan | United States of America | KF839521 | KF839549 | ||
IL_USA_02(F) | Michigan | United States of America | KF839522 | KF839550 | KF839576 | |
Lucilia infernalis | In_BRN_01(F) | Parc National de la Kibira | Burundi | KF839523 | KF839551 | KF839577 |
In_RWN_01(F) | Nyungwe Forest Reserve | Rwanda | JN792780 | JN792857 | JN813094 | |
Lucilia mexicana | Mx_USA_01(F) | New Mexico | United States of America | KF839524 | KF839552 | KF839578 |
Mx_USA_02(F) | New Mexico | United States of America | KF839525 | KF839579 | ||
Lucilia papuensis | Pa_AUS_01 | - | Australia | KF839526 | ||
Lucilia porphyrina | Po_AUS_01 | - | Australia | KF839527 | KF839553 | |
Lucilia sericata | S_AUS_01 (M) | Seaford | Australia | JN792746 | JN792824 | JN792668 |
S_FRC_01 (F) | Montferrier-Sur-Lez | France | JN792749 | JN792827 | JN792671 | |
S_JPN_01 (F) | Osaka | Japan | JN792754 | JN792831 | JN792678 | |
S_NAM_01 (F) | Possession Island | Namibia | JN792758 | JN792835 | JN792682 | |
S_SA_CT_07 (F) | Cape Town | South Africa | JN792766 | JN792843 | JN792690 | |
S_USA_01 (F) | Michigan | United States of America | JN792778 | JN792855 | JN792703 | |
Lucilia silvarum | Si_GER_01(F) | Kempen | Germany | KF839528 | KF839580 | |
Lucilia thatuna | Th_USA_01(F) | Del Norte Co. California | United States of America | KF839529 | KF839554 | KF839581 |
Th_USA_02(F) | Del Norte Co. California | United States of America | KF839530 | KF839555 | KF839582 |
One hind leg of each fly was used for DNA analysis. DNA was extracted using the Qiagen DNeasy tissue kit (Qiagen, Inc., Valencia, CA) according to the manufacturer’s instructions. Three genes were chosen for sequencing: 28S rRNA (28S), a nuclear gene that has been used in previous studies and would allow comparison with other studies (
Additional DNA sequences of 28S, Per and COI were obtained from GenBank (www.ncbi.nlm.nih.gov) (Table
Species | Locality | Accession Number | |||
---|---|---|---|---|---|
28S | Per | COI | |||
C. vicina | Bristol | UK | AJ300131 | AJ417702 | |
D. fasciata | - | Hawaii | AY074902 | ||
D. lucilioides | - | Hawaii | AY074903 | ||
D. robusta | - | Hawaii | AY074898 | ||
H. ligurriens | - | China | DQ345092 | ||
H. ligurriens | - | Taiwan | AY097334 | ||
H. ligurriens | - | Taiwan | DQ453493 | ||
H. pulchra | - | China | DQ345091 | ||
L. adiosoemartoi | - | Indonesia | AY074901 | ||
L. ampullacea | Langford | UK | AJ300137 | ||
L. ampullacea | Bristol | UK | DQ453487 | ||
L. ampullacea | - | Korea | EU925394 | ||
L. bazini | - | Taiwan | AY346450 | ||
L. bazini | - | China | DQ345082 | ||
L. caesar | Langford | UK | AJ300138 | AY417703 | |
L. caesar | Bristol | UK | DQ453488 | ||
L. caesar | - | Korea | EU880196 | ||
L. cluvia | New Orleans | USA | AJ551440 | DQ453490 | |
L. cluvia | Volusia Co. Florida | USA | JQ942371 | ||
L. coeruleiviridis | New York | USA | FJ650558 | ||
L. cuprina | - | China | DQ345087 | ||
L. cuprina | Honolulu | Hawaii | AJ417704 | ||
L. cuprina | Oahu | Hawaii | DQ453496 | ||
L. cuprina | - | Taiwan | AY097335 | ||
L. cuprina | - | Thailand | EU418577 | ||
L. cuprina | Tororo | Uganda | AJ417711 | ||
L. cuprina | Townsville | Australia | AJ417709 | AJ417710 | |
L. cuprina | Waianae | Hawaii | AJ417705 | ||
L. cuprina | Wallaceville | New Zealand | Y19108.1 | ||
L. cuprina | Noordhoek | South Africa | EU626549 | ||
L. cuprina | Cincinnati | USA | FJ650542 | ||
L. eximia | - | Brazil | DQ453491 | ||
L. hainanensis | - | Taiwan | AY346451 | ||
L. hainanensis | - | China | DQ345084 | ||
L. illustris | Langford | UK | AJ300136 | AJ551445 | |
L. illustris | - | Korea | EU880204 | ||
L. illustris | - | China | DQ345090 | ||
L. illustris | - | India | DQ200168 | ||
L. mexicana | San Francisco | USA | AJ551441 | DQ453492 | |
L. mexicana | California | USA | FJ650563 | ||
L. mexicana | California | USA | FJ650562 | ||
L. papuensis | - | China | DQ345085 | ||
L. porphyrina | - | Taiwan | AY097336 | ||
L. porphyrina | - | Japan | AY074900 | ||
L. porphyrina | - | China | DQ345089 | ||
L. richardsi | Usk | - | AJ551142 | ||
L. sericata | Perth | Australia | AB112833 | ||
L. sericata | Nerja | Spain | AJ417716 | ||
L. sericata | Kingsbury | UK | AJ417713 | ||
L. sericata | Hilerod | Denmark | AJ300140 | EF531193 | |
L. sericata | Harare | Zimbabwe | AJ417717 | ||
L. sericata | - | China | DQ345086 | ||
L. sericata | Langford | UK | AJ300139 | ||
L. sericata | Los Angeles | USA | AJ300141 | ||
L. silvarum | Durham | UK | AJ551443 | ||
L. silvarum | - | USA | FJ650564 | ||
L. silvarum | Linn Co., OR | USA | JQ942455 | ||
L. taiyuanensis | - | China | DQ345088 | ||
L. thatuna | San Francisco | USA | AJ551444 | DQ453489 | |
L. thatuna | Del Norte Co., California | USA | JQ942464 |
The states of the 14 morphological characters defined by
Binary coding of 14 morphological characters for the genera Lucilia and Hemipyrellia. 1 – Colour of the basicostal scale (0 = black/brown, 1 = white/cream); 2 – Number of postsutural acrostichal bristles (0 = two pairs, 1 = three pairs); 3 – Eye separation in the male (0 = distance of greater than the width of the third antennal segment, 1 = less than the width of the third antennal segment); 4 – Number of anterio-dorsal bristles on the mid tibia (0 = one, 1 = two); 5 – Colour of the palpi (0 = yellow/orange, 1 = black/brown); 6 – Subcostal sclerite (0 = bristles absent, 1 = bristles present); 7 – Colour of the squamae (0 = uniform white/cream, 1 = partially or totally brown); 8 – Wings (00 = hyaline, 01 = lightly infuscated, 11 = heavily infuscated); 9 – Eye separation in the female (0 = distance of greater than one quarter of the width of the head, 1 = less than one quarter of the width of the head); 10 – Colour of antennae (0 = uniformly dark, 1 = non-uniform); 11 – Male hypopygium (00 = inconspicuous, 01 = conspicuous, 11 = highly conspicuous); 12 – Colour of abdomen and thorax (0 = predominantly brassy green/green, 1 = predominantly purple/blue/black); 13 – Colour of the legs (00 = dark brown, 01 = brown/black, 11 = black); 14 – Lower squamal lobe (0 = setae absent, 1 = setae present). (
Species | Character number | |||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | |
Calliphora vicina | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 00 | 0 | 0 | 11 | 1 | 01 | 1 |
Hemipyrellia fernandica | 0 | 0 | 0 | 0 | 1 | 1 | 0 | 00 | 1 | 0 | 00 | 0 | 11 | 0 |
Hemipyrellia ligurriens | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 00 | 1 | 1 | 01 | 0 | 11 | 0 |
Hemipyrellia pulchra | 0 | 0 | 0 | 1 | 0 | ? | 0 | 00 | 0 | 1 | 00 | 0 | 11 | 0 |
Lucilia ampullacea | 0 | 0 | 1 | 0 | 0 | 1 | 0 | 00 | 0 | 0 | 00 | 0 | 01 | 0 |
Lucilia bufonivora | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 00 | 0 | 0 | 01 | 0 | 11 | 0 |
Lucilia coeruleiviridis | 1 | 0 | 1 | 0 | 0 | 0 | 0 | 00 | 1 | 1 | 00 | 0 | 00 | 0 |
Lucilia caesar | 0 | 0 | 1 | 0 | 0 | 1 | 0 | 00 | 0 | 0 | 11 | 0 | 01 | 0 |
Lucilia cluvia | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 00 | 1 | 0 | 00 | 0 | 00 | 0 |
Lucilia cuprina | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 00 | 0 | 0 | 01 | 0 | 11 | 0 |
Lucilia eximia | 0 | 0 | 1 | 0 | 0 | 0 | 1 | 00 | 0 | 1 | 00 | 0 | 00 | 0 |
Lucilia fayeae | 0 | 0 | 1 | 0 | 0 | 0 | 1 | 01 | 0 | 0 | 00 | 1 | 00 | 0 |
Lucilia illustris | 0 | 0 | 1 | 0 | 0 | 1 | 0 | 00 | 0 | 0 | 01 | 0 | 11 | 0 |
Lucilia infernalis | 0 | 1 | 1 | 0 | 0 | 1 | 1 | 11 | 0 | 1 | 00 | 1 | 01 | 0 |
Lucilia mexicana | 0 | 0 | 1 | 0 | 0 | 0 | 1 | 01 | 0 | 1 | 00 | 0 | 11 | 0 |
Lucilia papuensis | 0 | 0 | 1 | 1 | 0 | 1 | 1 | 01 | 0 | 1 | 00 | 0 | 11 | 0 |
Lucilia porphyrina | 0 | 0 | 1 | 0 | 0 | 1 | 1 | 01 | 1 | 0 | 00 | 1 | 00 | 0 |
Lucilia richardsi | 1 | 1 | 0 | 1 | 1 | 0 | 0 | 00 | 0 | 0 | 00 | 0 | 11 | 0 |
Lucilia sericata | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 00 | 0 | 0 | 00 | 0 | 11 | 0 |
Lucilia silvarum | 0 | 1 | 0 | 0 | 1 | 0 | 0 | 00 | 0 | 0 | 01 | 0 | 11 | 0 |
Lucilia thatuna | 1 | 1 | 1 | 0 | 0 | 0 | 0 | 00 | 1 | 0 | 00 | 0 | 11 | 0 |
Separate Bayesian inference analyses were performed on each gene in MrBayes (
A network analysis for the COI data was created using the NeighborNet algorithm in SplitsTree4 (Huson and Bryant 2008) and the uncorrected P-distance method.
The COI barcode sequences (~700 bp long, between base numbers 1490 and 2198) retrieved from on-line databases were aligned along with our new sequences (~640 bp long, between base numbers 1709 and 2353) for a region approximately 800 bp long in which every sequence overlapped the others by at least 490 bp. Bayesian inference analysis was performed in MrBayes (
Maximum parsimony analysis of the morphological data (Table
The zoogeographic distributions of species in the Luciliinae (Table
Zoogeographic distribution of species of Luciliinae included in this study. Symbols in brackets represent anthropogenic introductions.
Species | Region | ||||||
---|---|---|---|---|---|---|---|
Hawaii | Afrotropical | Australasian | Oriental | Palaearctic | Neararctic | Neotropical | |
Dysctritomyia spp. | X | ||||||
Hypopygiopsis spp. | X | X | |||||
Hemipyrellia spp. | X | X | X | ||||
H. fernandica | X | ||||||
L. infernalis | X | ||||||
L. cuprina | X | X | X | (X) | X | ||
L. sericata | (X) | (X) | X | X | X | (X) | |
L. silvarum | X | X | |||||
L. thatuna | X | ||||||
L. adiosoemartoi | X | ||||||
L. bazini | X | ||||||
L. hainanensis | X | ||||||
L. taiyuanensis | X | ||||||
L. papuensis | X | X | |||||
L. porphyrina | X | X | X | ||||
L. ampullacea | X | X | |||||
L. caesar | X | X | |||||
L. illustris | X | X | X | ||||
L. cluvia | X | X | |||||
L. coeruleiviridis | X | ||||||
L. mexicana | X | ||||||
L. fayeae | X | ||||||
L. eximia | X |
Sequencing of the 28S, Per and COI genes resulted in 1932 bp being aligned – 656 bp for 28S, 700 bp for Per and 576 bp for COI. A total of 46 specimens were sequenced for 28S, 41 specimens for Per and 39 specimens for COI. These sequences were submitted to GenBank (Table
The ILD test for 28S and Per showed these two genes to be highly congruent (p = 1.00) and the datasets were therefore concatenated for the analyses. The ILD test for 28S, Per and COI showed the combination of these genes to be incongruent (p = 0.03). Despite the incongruence between the nuclear (28S and Per) and mitochondrial (COI) data, these data sets were also concatenated and an analysis run on the total molecular evidence.
The Bayesian inference tree (Fig.
Bayesian inference tree constructed from concatenated nuclear genes 28S + Per. Posterior probabilities are indicated on nodes. Green box = Hemipyrellia fernandica. C = L. cuprina, Ca = L. caesar, Co = L. coeruleiviridis, CV = Calliphora vicina, Ex = L. eximia, Fa = L. fayeae, H = Hemipyrellia fernandica, IL = L. illustris, In = L. infernalis, Mx = L. mexicana, Pa = L. papuensis, Po = L. porphyrina, S = L. sericata, Si = L. silvarum, Th = L. thatuna, AUS = Australia, BRN = Burundi, CAN = Canada, CSR = Costa Rica, DOM = Dominican Republic, FRC = France, GER = Germany, JPN = Japan, NAM = Namibia, EGT = Egypt, RWN = Rwanda, SWZ = Switzerland, SA = South Africa, TAN = Tanzania, THA = Thailand, USA = United States of America, ZIM = Zimbabwe. DBN = Durban, CT = Cape Town.
In the Bayesian inference tree for the mitochondrial gene (COI) (Fig.
Bayesian inference tree constructed from mitochondrial gene COI. Posterior probabilities indicated on nodes. Green box = Hemipyrellia sp. Blue box = Dysctritomyia sp. C = L. cuprina, Ca = L. caesar, Co = L. coeruleiviridis, CV = Calliphora vicina, Ex = L. eximia, Fa = L. fayeae, H = Hemipyrellia fernandica IL = L. illustris, In = L. infernalis, Mx = L. mexicana, S = L. sericata, Si = L. silvarum, Th = L. thatuna, AUS = Australia, BRN = Burundi, CAN = Canada, CSR = Costa Rica, DOM = Dominican Republic, FRC = France, GER = Germany, JPN = Japan, NAM = Namibia, EGT = Egypt, RWN = Rwanda, SWZ = Switzerland, SA = South Africa, TAN = Tanzania, THA = Thailand, USA = United States of America, ZIM = Zimbabwe. DBN = Durban, CT = Cape Town.
The Bayesian inference tree for the incongruent concatenated total evidence molecular dataset (28S, Per and COI) (Fig.
Bayesian inference tree constructed from the concatenated nuclear (28S & Per) and mitochondrial (COI) genes. Posterior probabilities indicated on nodes. Green box = Hemipyrellia fernandica. C = L. cuprina, Ca = L. caesar, Co = L. coeruleiviridis, CV = Calliphora vicina, Ex = L. eximia, Fa = L. fayeae, H = Hemipyrellia fernandica IL = L. illustris, In = L. infernalis, Mx = L. mexicana, S = L. sericata, Si = L. silvarum, Th = L. thatuna, AUS = Australia, BRN = Burundi, CAN = Canada, CSR = Costa Rica, DOM = Dominican Republic, FRC = France, GER = Germany, JPN = Japan, NAM = Namibia, EGT = Egypt, RWN = Rwanda, SWZ = Switzerland, SA = South Africa, TAN = Tanzania, THA = Thailand, USA = United States of America, ZIM = Zimbabwe. DBN = Durban, CT = Cape Town.
The NeighborNet analysis (Fig.
NeighborNet network diagram constructed from COI data showing parasitic behaviour (coloured text) and previous sub-generic status of Lucilia according to
Bayesian inference analysis of the COI barcode data set generated a tree (Fig.
The strict consensus parsimony tree for the morphological characters was largely uninformative, forming only two clades, with the majority of the species being unresolved (tree not shown). The 50% majority rule consensus tree (Fig.
The majority rule consensus tree of the morphological characters (Fig.
Although only about half of the Lucilia species listed as valid by
It has already been established that L. sericata and L. cuprina show a case of ancient introgression, and that they still interbreed (
In the Bayesian inference trees based on mitochondrial (COI) (Fig.
Lucilia caesar and L. illustris also share haplotypes (
These three species pairs highlight the need for using more than one gene to identify species, as has been suggested in previous studies (
The Luciliinae showed two strong patterns underlying their diversification: biogeographical radiation and the diversification of parasitism.
The analyses (summarised in Fig.
Lucilia sericata, L. cuprina, L. thatuna and L. silvarum form a clade of facultatively parasitic species, with L. sericata and L. cuprina being primary facultative parasites. This group is geographically diverse, with only L. thatuna being restricted to one region, the United States of America. Likewise, L. caesar and L. illustris form a clade that represents secondary facultative parasites. Lucilia illustris is Holarctic, while L. caesar is restricted to the Palaearctic (
Many Lucilia species are myiasis-causing (
Lucilia Robineau-Desvoidy, 1830 (type species: Lucilia caesar (Linnaeus, 1758) has a complex nomenclatural history that is integrally related to its biogeographical and dietary radiation. Several authors including Bigot, van der Wulp, Brauer and Bergenstamm, Girschner, Hough, Kramer, Shannon and Malloch (
Phaenicia Robineau-Desvoidy, 1863 (type species: Phaenicia concinna Robineau-Desvoidy, 1863 = Musca sericata Meigen, 1826) has a history of varied usage.
In the network analysis (Fig.
Bufolucilia Townsend, 1919 (type species: Lucilia bufonivora) includes the species bufonivora, silvarum and (by monophyly) elongata, which are found in Europe and North America. Bufolucilia forms a part of the clade that includes most of the facultatively parasitic Lucilia species (Fig.
Phumonesia Villeneuve, 1914 and Roubaudiella Séguy, 1925 (type species: Phumonesia infernalis Villeneuve, 1914 = Roubaudiella caerulea Robineau-Desvoidy, 1863) are monotypic genera founded on the same species, and therefore objective synonyms. The only species shows affinities with Hemipyrellia in some analyses (Fig.
Similarly, Francilia Shannon, 1924, and Acrophagella Ringdahl, 1942, are objective synonyms because they are based on the same species. Several other genus-group taxa have been erected within the Luciliinae, including Caesariceps Rodendorf, 1926, Dasylucilia Rodendorf, 1926, Luciliella Malloch, 1926 and Viridinsula Shannon, 1926. Their status needs assessment, and the results presented here suggest that morphological analyses alone will not be sufficient. Phylogenetic studies including a selection of both nuclear and mitochondrial genes are recommended.
Hemipyrellia Townsend, 1918 (type species: Lucilia fernandica Macquart, 1855) was erected as a genus by Townsend (1918) and revised by
In two studies of Australian blowflies, Hemipyrellia was found to be a sister-group to Lucilia (
Dyscritomyia Grimshaw, 1901 (type species: Prosthetochaeta robusta Grimshaw, 1901) contains 35 nominal species that are all found exclusively on the Hawaiian Islands (
This study used 20 species of Lucilia in the COI analysis while the previous studies used six and 13 species, respectively (
Hypopygiopsis Townsend, 1916 (type species: Hypopygiopsis splendens Townsend, 1916 = Hypopygiopsis fumipennis Walker, 1856) is restricted to the Asian and Australasian regions of the world (
Lucilia sericata and L. cuprina are indeed sister-species. Lucilia mexicana is confirmed to be paraphyletic with respect to L. coeruleiviridis, possibly as a result of hybridisation and introgression. Lucilia caesar and L. illustris are both paraphyletic and further studies with different genes are needed to determine if these two species can be identified using molecular methods. Hemipyrellia should be synonymised with Lucilia because this genus sits within Lucilia in all of the analyses conducted in this study. Dyscritomyia requires further studies to confirm its phylogenetic positioning with regard to Lucilia because taxon sampling appears to have an impact on the analysis. The limited number of sequences available for Hypopygiopsis and the apparent misidentification of sequences prevent any conclusions being drawn about its relationship to Lucilia. In this study we have identified at least three cases of misidentified sequences from GenBank, which is a well-known problem (
We thank Dave Emery, Georg Goergen, Chris Kelly, Ashley Kirk-Spriggs, Nicky Lunt, Rich Merritt, Hideharu Numata, Cameron Richards, Kiyoshi Saigusa, Kabkaew Sukontason, Robyn Tourle, James Wallman, Terry Whitworth and Claude Wyss for providing us with specimens. Funding was provided by the National Research Foundation (NRF) of South Africa. Any opinion, findings and conclusions or recommendations expressed in this material are those of the author and do not necessarily reflect the views of the National Research Foundation.