Research Article |
Corresponding author: Silas Bossert ( sb2346@cornell.edu ) Academic editor: Denis Brothers
© 2022 Silas Bossert, Simon van Noort.
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:
Bossert S, van Noort S (2022) A group of two: Scrapter peringueyi is not a synonym of Scrapter heterodoxus (Hymenoptera, Colletidae, Scraptrinae). African Invertebrates 63(1): 1-18. https://doi.org/10.3897/afrinvertebr.63.76934
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Scrapter is a genus of colletid bees with a primary distribution centered in Southern Africa. The genus currently comprises 68 recognized species, which are divided into nine species groups, ranging from one to 29 included species. The Scrapter heterodoxus group is presently considered to be the only monotypic group, because of synonymization of Scrapter heterodoxus with Scrapter peringueyi in a previous revision of the genus. A comparative examination of these two species using both morphological assessment and molecular sequence data from the COI barcode region supported the recognition of S. peringueyi as a valid species, which we accordingly resurrect as the second species of the Scrapter heterodoxus species group. We provide high resolution images of the type specimens for both species and updated diagnoses to enable their separation from all other species of Scrapter.
Bees, COI, DNA barcoding, Afrotropical, morphology
Scrapter Lepeletier & Serville, 1828 is a genus of colletid bees endemic to Africa (
In the past, the phylogenetic relationships of Scrapter to other colletid lineages proved difficult to establish based on morphology alone (
Scrapter is a morphologically heterogeneous genus (
We located and examined the type specimens of S. heterodoxus and S. peringueyi in the collections of the Iziko South African Museum, Cape Town (
To compare the DNA sequences of Scrapter heterodoxus and S. peringueyi, we obtained sequence data for both species. One COI sequence for S. heterodoxus was retrieved from GenBank (identifier MH578427) and we extracted another COI barcode from a UCE assembly of the same species (from
Examination of the sequence alignment by eye revealed that for each species the two barcode sequences differed in length but were otherwise identical across the shared positions. Since we were interested in examining the interspecific distance between S. heterodoxus and S. peringueyi, we only retained the longest DNA sequence for each species. This led to a sequence alignment of 658 nucleotides (658 present positions for S. heterodoxus and 657 for S. peringueyi). We estimated the evolutionary distance between these two sequences by quantifying the proportion of sites at which nucleotides differed (p-distance). We uploaded the reference COI sequence of S. peringueyi to NCBI GenBank where it can be retrieved under identifier MZ682106. The sequence alignment of all four sequences can be found as Suppl. material
Images were acquired at
Scrapter
Lepeletier & Serville, 1828: 403 (not Scrapter Lepeletier, 1841: 260). Type species: Scrapter bicolor Lepeletier & Serville, 1828, by subsequent designation in
Polyglossa
Friese, 1909: 123. Type species: Polyglossa capensis Friese, 1909, by subsequent designation in
Strandiella
Friese, 1912: 181. Type species: Strandiella longula Friese, 1912 = Scrapter niger Lepeletier & Serville, 1828, by designation in
Polyglossa (Parapolyglossa)
Brauns, 1929: 134. Type species: Polyglossa heterodoxa Cockerell, 1921, by subsequent designation in
Polyglossa heterodoxa Cockerell, 1921: 204.
Lectotype
: South Africa: Cape Town, leg. F. Foly, ♂,
♂: the male of S. heterodoxus differs from all other Scrapter species except S. peringueyi in possessing the unique combination of the following characters: body size of ≥ 12 mm, hind femur greatly enlarged, hind tibia strongly broadened apically (Figs
♀: The female differs from most species of Scrapter, except S. caesariatus Eardley, 1996, S. peringueyi and those of the S. nitidus and S. basutorum species groups, in having a medio-longitudinally depressed clypeus (“mediolongitudinal sulcus” in
The females of S. heterodoxus and S. peringueyi are difficult to distinguish at times, whereas the males are easily recognized. The published sequence data of S. heterodoxus from previous molecular-phylogenetic treatments (
Polyglossa peringueyi Cockerell, 1921: 205.
Holotype: South Africa: Knysna, C. C., October 1916, leg. L. Péringuey, ♀,
Scrapter peringueyi is morphologically very similar to S. heterodoxus. ♂: the male of S. peringueyi differs from that of S. heterodoxus in the shape of the projecting apical portion of the hind tibia, which is parallel-sided (tapering in S. heterodoxus) (Figs
♀: the female of S. peringueyi differs from S. heterodoxus in the same characters as the male, except for the shape of the hind tibia. The surface sculpturing of the basal zone of the propodeum is substrigulate, whereas it is rugulose in S. heterodoxus (Figs
Comparison of the shape of the male hind leg tibia and propodeal sculpture. A Scrapter peringueyi (Cockerell, 1921), stat. rev. hind leg tibial apex, non-type male specimen (deposited in
Scrapter heterodoxus and S. peringueyi were described as species by Cockerell in the same publication (
Prior and subsequent to
Mapping the distributions of S. peringueyi and S. heterodoxus based on the 133 examined specimens reveals slightly different distribution patterns for the two species (Fig.
We thank Bryan N. Danforth (Cornell University) for providing us access to the specimens deposited in the Cornell University Insect Collection and Werner Strumpher (South African National Collection of Insects) for help in locating the type specimens. We thank the reviewers and the editorial team of African Invertebrates for their constructive feedback on the manuscript. This work was supported by U.S. National Science Foundation grants DEB-2127744 and DEB-0814544.
Multiple sequence alignment of the examined species of Scrapter
Data type: multiple sequence alignment
Explanation note: Multiple sequence alignment of the Scrapter heterodoxus and Scrapter peringueyi sequences analyzed in the present study. The alignment file is in Fasta format.
Specimen metadata
Data type: occurences
Explanation note: Specimen metadata for the 133 examined specimens in Darwin Core format.