Research Article |
Corresponding author: Martin H. Villet ( martin.villet@gmail.com ) Academic editor: Burgert Muller
© 2021 Martin H. Villet, Shelley Edwards.
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:
Villet MH, Edwards S (2021) The cicada genus Tugelana Distant, 1912 (Hemiptera, Cicadidae): phylogenetic position and conservation status. African Invertebrates 62(2): 399-410. https://doi.org/10.3897/afrinvertebr.62.66891
|
The cicada genus Tugelana Distant, 1912 is monotypic and endemic to south-eastern Africa. Material was not available for a recent molecular phylogeny of its tribe, so its precise phylogenetic placement is unestablished. Consequently, a 627 bp sequence of the cytochrome oxidase gene was obtained and its candidate relatives identified as several species of Platypleura Amyot & Audinet-Serville, 1843 using the BOLD Identification System and NCBI Genbank’s BLAST. Bayesian inference analyses indicated that the type species, the Maputaland Orangewing Cicada Tugelana butleri Distant, 1912, is closely related to the Dune Koko Orangewing Cicada Platypleura zuluensis Villet, 1989, which has a geographical distribution that is parapatric with T. butleri and which has aberrant genitalia for a member of Platypleura. This pair of species is placed fairly deep within the African clade of Platypleura. We therefore formally recognized Platypleura Amyot & Audinet-Serville, 1843 as a senior synonym of Tugelana Distant, 1912, syn. nov., and assign T. butleri Distant, 1912 to Platypleura as Platypleura butleri (
Biogeography, cytochrome oxidase I, genetic barcode, phylogeny, synonymy, taxonomy
The monotypic southern African endemic genus Tugelana Distant, 1912 was first assigned to the tribe Hamzini Distant, 1904 (
Biogeographically, Tugelana is southern African (
The wing colouration and pattern (Fig.
Geographical distribution of P. butleri and P. zuluensis within southern Africa, with insets of the two species (specimen scale lines = 10 mm). The distribution of P. butleri has a known standard Area of Occupancy (AOO) of 36 km2 (nine localities) and an Extent of Occurrence (EOO) of 6360 km2. Abbreviations: EC = Eastern Cape, eS = eSwatini, G = Gauteng, KZN = KwaZulu-Natal, L = Limpopo, Les = Lesotho, M = Mpumalanga, NC = Northern Cape, WC = Western Cape.
Since these observations create some doubt about the taxonomic distinctness of Tugelana and Platypleura sensu stricto, there is reason to seek new evidence of the relationships between these taxa. We provide molecular evidence to clarify this problem, and some notes on the biogeography and conservation status of the species.
A specimen of T. butleri, now deposited in the Albany Museum, Makhanda, was collected by Adrian Armstrong in wooded grassland hillside in the Manzengwenya area (-27°15.17'S, 32°46.42'E) of the Isimangaliso Wetland Park, South Africa, on 26th March, 2016. Genomic DNA was extracted from the tympanal muscle of the dried, pinned specimen by a salt extraction method (
To get a first approximation of the relationships of T. butleri, the COI sequence was submitted to the on-line BOLD Identification System (IDS) for COI (https://www.boldsystems.org/index.php/IDS_OpenIdEngine) to search all records on the Barcode Of Life Database (BOLD) (~8,229,467 sequences at the time, including privately held data), and to NCBI Genbank’s Basic Local Alignment Search Tool (BLAST) (
The closest genus-level relatives of T. butleri were sought using phylogenetic analyses. Based on the results of the IDS and BLAST searches, homologous sequences of four gene regions (mitochondrial 16S, COI and COII, and nuclear EF1α) from the African species of Platypleura in the open-access data set of Price et al. (Suppl. material
Saturation of the different codon positions (each codon position separately, and codon positions 1 and 2 together) of each protein-coding region marker (COI, COII, and EF1α) were tested using DAMBE v.7.2.152 (
Two Bayesian inference (BI) analyses were conducted with MrBayes v.3.2.2 (
The second BI analysis also used the nucleotide substitution models, but used the codon model within MrBayes (
A third phylogenetic tree was produced using maximum likelihood methods in Garli v.2.01 (
Specimens were sought in museums in South Africa, England, France, Belgium, Germany and Sweden, and found in the Albany Museum, Makhanda; the Natural History Museum, London; the private collection of R. D. Steven; and the National Collection of Insects, Pretoria. Locality and habitat data were obtained from the labels of specimens and Kew’s GEOCAT software (http://geocat.kew.org/editor) was used to calculate the standard Area of Occupancy (AOO) and Extent of Occurrence (EOO) of T. butleri (
A 627 bp fragment of the COI gene was obtained. The electropherogram showed no heterozygous peaks; there were no unexpected stop codons; and no single- or double-base indels appeared when it was aligned with multiple sequences drawn from ten platypleurine genera selected from the
The BOLD IDS reported “no match” for the sequence, but the top three hits were P. zuluensis (95.51% similarity), Platypleura plumosa Germar, 1834 (91.15%) and P. capensis (90.95%), which are all African platypleurine species (Table
The top twenty greatest similarities found by BOLD IDS. None of these qualified as a taxonomic match by BOLD criteria.
Rank | Genus | Similarity (%) | Status |
---|---|---|---|
1 | Platypleura zuluensis | 95.51 | Published |
2 | Platypleura plumosa | 91.15 | Published |
3 | Platypleura capensis | 90.95 | Published |
4 | Platypleura capensis | 90.95 | Published |
5 | Platypleura capensis | 90.95 | Published |
6 | Platypleura capensis | 90.95 | Published |
7 | Platypleura capensis | 90.95 | Published |
8 | Platypleura capensis | 90.95 | Published |
9 | Platypleura capensis | 90.73 | Published |
10 | Platypleura capensis | 90.73 | Published |
11 | Platypleura capensis | 90.73 | Published |
12 | Platypleura capensis | 90.73 | Published |
13 | Platypleura capensis | 90.73 | Published |
14 | Platypleura capensis | 90.73 | Published |
15 | Platypleura capensis | 90.73 | Published |
16 | Platypleura capensis | 90.73 | Published |
17 | Platypleura capensis | 90.73 | Published |
18 | Platypleura capensis | 90.73 | Published |
19 | Platypleura capensis | 90.73 | Published |
20 | Platypleura capensis | 90.73 | Published |
The top 45 greatest similarities found by BLAST, with their assessment criteria.
Rank | Description | Query Cover | E-value | Percent Identity | Accession |
---|---|---|---|---|---|
1 | Platypleura plumosa MHV0534 | 99% | 0.0 | 90.66% | FJ169057 |
2 | Platypleura plumosa MHV0555 | 99% | 0.0 | 90.66% | FJ169070 |
3 | Platypleura plumosa MHV1040 | 99% | 0.0 | 90.66% | FJ169175 |
4 | Platypleura plumosa MHV0329 | 99% | 0.0 | 90.51% | FJ169023 |
5 | Platypleura plumosa MHV0333 | 99% | 0.0 | 90.51% | FJ169026 |
6 | Platypleura plumosa MHV0501 | 99% | 0.0 | 90.51% | FJ169052 |
7 | Platypleura plumosa MHV0558 | 99% | 0.0 | 90.51% | FJ169072 |
8 | Platypleura plumosa MHV0567 | 99% | 0.0 | 90.51% | FJ169078 |
9 | Platypleura plumosa MHV1041 | 99% | 0.0 | 90.51% | FJ169176 |
10 | Platypleura plumosa MHV1042 | 99% | 0.0 | 90.51% | FJ169177 |
11 | Platypleura plumosa MHV1043 | 99% | 0.0 | 90.51% | FJ169178 |
12 | Platypleura plumosa MHV1045 | 99% | 0.0 | 90.51% | FJ169179 |
13 | Platypleura plumosa MHV1046 | 99% | 0.0 | 90.51% | FJ169180 |
14 | Platypleura plumosa MHV0324 | 99% | 0.0 | 90.35% | FJ169021 |
15 | Platypleura plumosa MHV0327 | 99% | 0.0 | 90.35% | FJ169022 |
16 | Platypleura plumosa MHV0422 | 99% | 0.0 | 90.35% | FJ169040 |
17 | Platypleura plumosa MHV0616 | 99% | 0.0 | 90.35% | FJ169110 |
18 | Platypleura plumosa MHV1019 | 99% | 0.0 | 90.35% | FJ169166 |
19 | Platypleura plumosa MHV1021 | 99% | 0.0 | 90.35% | FJ169168 |
20 | Platypleura plumosa MHV1039 | 99% | 0.0 | 90.35% | FJ169174 |
21 | Platypleura plumosa MHV0200 | 99% | 0.0 | 90.20% | FJ168999 |
22 | Platypleura plumosa MHV0259 | 99% | 0.0 | 90.20% | FJ169010 |
23 | Platypleura plumosa MHV0536 | 99% | 0.0 | 90.20% | FJ169059 |
24 | Platypleura plumosa MHV0537 | 99% | 0.0 | 90.20% | FJ169060 |
25 | Platypleura plumosa MHV0564 | 99% | 0.0 | 90.20% | FJ169075 |
26 | Platypleura plumosa MHV1020 | 99% | 0.0 | 90.20% | FJ169167 |
27 | Platypleura sp. 13 MHV1016 | 99% | 0.0 | 90.20% | FJ169164 |
28 | Platypleura sp. 13 MHV1018 | 99% | 0.0 | 90.20% | FJ169165 |
29 | Platypleura sp. 12 MHV0014 | 99% | 0.0 | 90.08% | FJ168986 |
30 | Platypleura sp. 12 MHV0571 | 99% | 0.0 | 90.08% | FJ169080 |
31 | Platypleura sp. 12 MHV0572 | 99% | 0.0 | 90.08% | FJ169082 |
32 | Platypleura sp. 12 MHV0573 | 99% | 0.0 | 90.08% | FJ169083 |
33 | Platypleura sp. 12 MHV0586 | 99% | 0.0 | 90.08% | FJ169092 |
34 | Platypleura sp. 12 MHV0603 | 99% | 0.0 | 90.08% | FJ169102 |
35 | Platypleura capensis MHV0021 | 99% | 0.0 | 90.05% | FJ168988 |
36 | Platypleura plumosa MHV0320 | 99% | 0.0 | 90.05% | FJ169018 |
37 | Platypleura plumosa MHV0421 | 99% | 0.0 | 90.05% | FJ169039 |
38 | Platypleura plumosa MHV0538 | 99% | 0.0 | 90.05% | FJ169061 |
39 | Platypleura plumosa MHV0540 | 99% | 0.0 | 90.05% | FJ169063 |
40 | Platypleura sp. 13 MHV1015 | 99% | 0.0 | 90.05% | FJ169163 |
41 | Platypleura plumosa MHV1037 | 99% | 0.0 | 89.92% | FJ169173 |
42 | Platypleura plumosa MHV0610 | 99% | 0.0 | 89.89% | FJ169106 |
43 | Platypleura plumosa MHV0614 | 99% | 0.0 | 89.89% | FJ169109 |
44 | Platypleura sp. 11 MHV0859 | 99% | 0.0 | 89.89% | FJ169137 |
45 | Platypleura sp. 11 MHV0862 | 99% | 0.0 | 89.89% | FJ169139 |
The phylogenetic tree reconstructions using the three differing algorithms produced congruent topologies, and the overall topology unsurprisingly matched that found in
Bayesian Inference (BI) phylogenetic tree constructed using a codon nucleotide substitution model. Tugelana butleri is highlighted with a black box. Posterior probabilities (PP) from the two BI phylogenetic reconstructions are indicated above the nodes numerically (BIPPc = codon substitution model, BIPPn = nucleotide substitution model), and the bootstrap support values from the Maximum Likelihood analyses are shown in percentages below the nodes (MLBS). Nodes with BIPP > 0.95 and MLBS > 75 are considered well-supported.
Although there are several with no provenance, other specimens of Tugelana butleri have been collected from nine identified localities in Mozambique and South Africa. Its known standard Area of Occupancy (AOO) is 36 km2 (nine localities), its Extent of Occurrence (EOO) is 6360 km2. The labels of two specimens record the habitat as “coastal dune vegetation” at Lake Sibaya (leg. R. Perissinotto & L. Clennell) and “wooded grassland hillside” in the Manzengwenya area of Isimangaliso Wetland Park (leg. Adrian Armstrong).
Consistent molecular evidence was found that T. butleri and P. zuluensis are closely related. Platypleura zuluensis has been collected from late November to late February in coastal forests from Hermanus to at least the Mozambique border (Fig.
Platypleura Amyot & Audinet-Serville, 1843: 465
= Tugelana Distant, 1912: 646, syn. nov.
Platypleura butleri (Distant, 1912: 646), comb. nov.
= Tugelana butleri Distant, 1912: 646
= Platypleura maritzburgensis Distant, 1913: 79 (teste
The geographical distribution of P. butleri comb. nov. appears to be restricted to Maputaland, a wedge of wooded grassland on the coastal plateau east of the Lebombo Mountains and south of Maputo Bay, which is reflected in its vernacular name, the Maputaland Orangewing Cicada. Since it is known from only nine localities, it is not well sampled, so its Area of Occurrence may be a misleading indication of its conservation status. However, its estimated Extent of Occurrence (~6360 km2) suggests that its IUCN status may qualify as “Vulnerable” (
We warmly thank Adrian Armstrong (Conservation Research and Assessment Division, Ezemvelo KZN Wildlife, South Africa) for bringing his specimen to our attention; Fred Gess (Albany Museum, Makhanda), Mick Webb (Natural History Museum, London), Richard Steven (Pretoria), and Ian Millar (National Collection of Insects, Pretoria) for allowing access to specimens in their care. The specimen was obtained under Ordinary Permit number OP 1422/2016 issued to A. Armstrong in pursuance of the provisions of the Nature Conservation Ordinance No 15 of 1974, Chapter 7 and the Regulations framed thereunder. This work was funded by the Rhodes University Research Committee.
Table S1, Figures S1, S2
Data type: docx. file
Explanation note: Table S1. Specimen sampling for the Platypleura genus tree. Partial sequence of COI for Platypleura butleri voucher number MHV1928. Figure S1. Maximum likelihood phylogenetic tree for the Platypleurini. Confidence values (MLBS) at the nodes are the bootstrap values, presented in percentages. MLBS > 75 is considered well-supported. Figure S2. Bayesian Inference phylogenetic tree, using nucleotide substitution models, for the Platypleurini. Confidence values (BIPPn) at the nodes are the posterior probabilities, presented numerically. BIPPn > 95 is considered well-supported.
Locality records
Data type: COL (excel table)
Explanation note: Locality data for Platypleura butleri (= Tugelana butleri).