Phylogeny of the flea beetles (Galerucinae: Alticini) and the position of Aulacothorax elucidated through anchored phylogenomics (Coleoptera: Chrysomelidae: Alticini)

Abstract

The Alticini comprise 601 genera and 10,000 species, including plant pests. Their phylogeny remains largely unresolved, inhibiting taxonomic stability, specimen identification and biological understanding. Here, we generated a genomic dataset using Anchored Hybrid Enrichment (AHE) for 54 genera of Alticini, 16 of Galerucini, and 40 of other Chrysomelidae to test the monophyly of Alticini, and its genus groups, and to examine the utility of established diagnostic characters. Maximum likelihood and coalescent phylogenetic analyses produced resolved and overall congruent topologies. Synetinae was sister to Cassidinae + Eumolpinae + Lamprosomatinae + Cryptocephalinae, supporting its recognition as valid. Within Galerucinae, Aulacothorax Boheman was found as sister to Galerucini + Alticini (each monophyletic). Tribe Serraticollini White stat. rev. is reinstated as valid, as the oldest available name for the higher lineage containing Aulacothorax. We extend Crowson's classification, with Alticini, Galerucini, and Serraticollini united under Galerucinae. We transfer genera Chalaenosoma Jacoby, Demarchus Jacoby, and Mandarella Duvivier from Alticini to Galerucini incertae sedis, and confirm prior transfers of Hespera Weise, Luperomorpha Weise and Nonarthra Baly from Alticini to Galerucini incertae sedis. Galerucini and Alticini are reciprocally monophyletic following these transfers. Our work recovered multiple evolutionary origins of jumping hind legs in Galerucinae, hindering straightforward morphological diagnosis of tribes. We provide diagnoses for Alticini, Galerucini and Galerucinae, but these require dissection of female genitalia. We achieved some phylogenetic resolution within Alticini, but found few adult morphological characters to define subclades. Our results indicate that with future denser taxon sampling, AHE phylogenomics could provide a robust basis for subtribal classifications.

Giant Sex Chromosomes in Omophoita Species (Coleoptera, Chrysomelidae): Structural and Evolutionary Relationships Revealed by Zoo-FISH and Comparative Genomic Hybridization (CGH)

“…Nevertheless, the sex chromosomes of all species showed conservation of their general genomic composition, with minor species-specific regions. Although not including all Omophoita species that were investigated here, previous molecular phylogenetic reconstructions of flea beetles suggest that the Oedionychina group has diverged in the middle Cretaceous (~100 mya) [ 29 ] even though Omophoita is considered the most derived genus [ 48 ]; this age can also be deduced as the origin of this giant sex chromosome system since it is shared by all subtribe members [ 26 ]. Older achiasmatic sex chromosome systems are observed in other Arthropods, such as Hemiptera true bugs [ 49 , 50 ], while for the fly Drosophila albomicans , the switch from chiasmatic to achiasmatic is dated to 0.55 mya [ 51 ].…”

Up and down from North to South: Latitudinal Distribution of Flea Beetle Genera in Continental Africa (Coleoptera, Chrysomelidae, Galerucinae, Alticini)

“…Species-level data may be affected by taxonomic uncertainties and potential misidentifications [47], while genera are comparatively stable taxonomic entities, especially in areas where faunal knowledge is still very partial. Although some authors have recently attributed the genera Hespera and Luperomorpha to the "Galerucini incerta sedis" group [24,48], in this work, they were considered Alticini, pending a definite taxonomic collocation.…”

“…Alticini, defined as "flea beetles" due to their ability to jump, are the largest and most diverse tribe of leaf beetles in the subfamily Galerucinae, which also includes pests and alien species [18][19][20][21][22][23]. They occur worldwide, except in the polar regions, with 601 genera and about 10,000 species [24]. Most are highly specialized phytophagous insects that are primarily associated with herbaceous plants and, to a lesser extent, shrubs and trees.…”

Argopistes Motschulsky from Madagascar with descriptions of six new species (Coleoptera, Chrysomelidae, Galerucinae, Alticini)

“… Nadein (2015) , through a morphological-based cladistic analysis, attributed Argopistes to the subtribe Diboliina with Dibolia Latreille, Megistops Boheman, and Paradibolia Baly. More recent papers based on the use of molecular data considered Argopistes closely related to Apteropeda Chevrolat ( Hlaka et al 2022 ), Dibolia , and Apteropeda ( Letsch and Beran 2023 ), or Dibolia and Sphaeroderma Stephens ( Douglas et al 2023 ). Nevertheless, all authors agreed that additional molecular data and denser taxon sampling are required to provide a robust basis for establishing internal relationships among Alticini and possible subtribal classifications.…”