The Camponotus subgenus Myrmosaga subgen. rev. from the Malagasy region is revised based on analysis of both qualitative morphological characters and morphometric traits. The multivariate analysis used the Nest Centroid (NC)-clustering method to generate species hypotheses based on 19 continuous morphological traits of minor workers. The proposed species hypotheses were confirmed by cumulative Linear Discriminant Analysis (LDA). Morphometric ratios for the subsets of minor and major workers were used in species descriptions and redefinitions. The present study places the subgenus Myrmopytia syn. nov. in synonymy to Myrmosaga . It recognizes 38 species, of which 19 are newly described: C. aina sp. nov. , C. aro sp. nov. , C. asara sp. nov. , C. atimo sp. nov. , C. bemaheva sp. nov. , C. bozaka sp. nov. , C. daraina sp. nov. , C. harenarum sp. nov. , C. joany sp. nov. , C. karsti sp. nov. , C. kelimaso sp. nov. , C. lokobe sp. nov. , C. mahafaly sp. nov. , C. niavo sp. nov. , C. rotrae sp. nov. , C. sambiranoensis sp. nov. , C. tapia sp. nov. , C. tendryi sp. nov. , C. vano sp. nov. Eleven species are redescribed: C. aurosus Roger, C. cervicalis Roger, C. dufouri Forel, C. gibber Forel, C. hagensii Forel, C. hova Forel, C. hovahovoides Forel, C. immaculatus Forel, C. quadrimaculatus Forel, C. roeseli Forel, C. strangulatus Santschi. The following are raised to species and redescribed: C. becki Santschi stat. nov. , C. boivini Forel stat. rev. , C. cemeryi Özdikmen stat. rev. , C. mixtellus Forel stat. nov. , C. radamae Forel stat. nov. Camponotus maculatus st. fairmairei Santschi syn. nov. , is synonymized under C. boivini . The following are synonymized under C. cervicalis : Camponotus cervicalis gaullei Santschi, syn. nov. ; Camponotus perroti Forel, syn. nov. ; Camponotus perroti aeschylus Forel, syn. nov. ; Camponotus gerberti Donisthorpe, syn. nov. Camponotus dufouri imerinensis Forel, syn. nov. is a synonym of C. dufouri , Camponotus hova var. obscuratus Emery, syn. nov. is a synonym of C. hova , Camponotus quadrimaculatus opacata Emery, syn. nov. is a synonym of C. immaculatus , Camponotus maculatus st. legionarium Santschi, syn. nov. is a synonym of C. roeseli , Camponotus hova maculatoides Emery, syn. nov. is a synonym of C. strangulatus . The following are synonymized under C. quadrimaculatus : Camponotus kelleri Forel, syn. nov. , Camponotus kelleri var. invalidus Forel, syn. nov. , Camponotus quadrimaculatus sellaris Emery, syn. nov. As C. imitator Forel, C. liandia Rakotonirina & Fisher, and C. lubbocki Forel have been recently described and redescribed, only diagnoses and taxonomic discussions are provided. This revision also includes an illustrated species identification key, taxonomic discussions, images, and distribution maps for each species superimposed on the ecoregions of Madagascar.
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Taxonomic revision of the Malagasy Aphaenogaster swammerdami group (Hymenoptera: Formicidae)
Background Madagascar is famous for its extremely rich biodiversity; the island harbors predominantly endemic and threatened communities meriting special attention from biodiversity scientists. Continuing ongoing efforts to inventory the Malagasy ant fauna, we revise the species currently placed in the myrmicine genus Aphaenogaster Mayr. One species described from Madagascar, Aphaenogaster friederichsi Forel, is synonymized with the Palearctic A. subterranea Latreille syn. nov. This species is considered neither native to Madagascar nor established in the region. This revision focuses on the balance of species in the A. swammerdami group which are all endemic to Madagascar. Methods The diversity of the Malagasy Aphaenogaster fauna was assessed via application of multiple lines of evidence involving quantitative morphometric, qualitative morphological, and DNA sequence data. (1) Morphometric investigation was based on hypothesis-free Nest Centroid clustering (NC-clustering) combined with PArtitioning based on Recursive Thresholding (PART) to estimate the number of morphological clusters and determine the most probable boundaries between them. This protocol provides a repeatable and testable approach to find patterns in continuous morphometric data. Species boundaries and the reliability of morphological clusters recognized by these exploratory analyses were tested via confirmatory Linear Discriminant Analysis (LDA). (2) Qualitative, external morphological characteristics (e.g., shape, coloration patterns, setae number) were subjectively evaluated in order to create a priori grouping hypotheses, and confirm and improve species delimitation. (3) Species delimitation analyses based on mitochondrial DNA sequences from cytochrome oxidase I (COI) gene fragments were carried out to test the putative species previously delimited by morphological and morphometric analyses. Results Five species can be inferred based on the integrated evaluation of multiple lines of evidence; of these, three are new to science: Aphaenogaster bressleri sp. n ., A. gonacantha (Emery, 1899), A. makay sp. n. , A. sahafina sp. n. , and A. swammerdami Forel, 1886. In addition, three new synonymies were found for A. swammerdami Forel, 1886 ( A. swammerdami clara Santschi, 1915 syn. n. , A. swammerdami curta Forel, 1891 syn. n. and A. swammerdami spinipes Santschi, 1911 syn. n. ). Descriptions and redefinitions for each taxon and an identification key for their worker castes using qualitative traits and morphometric data are given. Geographic maps depicting species distributions and biological information regarding nesting habits for the species are also provided.
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- Award ID(s):
- 1655076
- NSF-PAR ID:
- 10219014
- Date Published:
- Journal Name:
- PeerJ
- Volume:
- 9
- ISSN:
- 2167-8359
- Page Range / eLocation ID:
- e10900
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- https://doi.org/10.7717/peerj.10900
