Galerucinae, Latreille, 1802

Galerucinae View in CoL

Galerucinae Latreille, 1802 View in CoL are the most diverse group of Chrysomelidae View in CoL with approximately 15,000 species worldwide, with the greatest diversity in tropical regions ( Nadein and Bezděk 2014, Nie et al. 2017b). In Brazil, 1,916 species in 202 genera, representing 31.5% of the Chrysomelidae View in CoL fauna, are registered.

The relationship of Galerucinae View in CoL s. str. (‘true’ galerucines) and Alticini View in CoL / Alticinae is an active research area since they were considered traditionally as distinct subfamilies ( Seeno and Wilcox 1982, Furth and Suzuki 1998). This classification was based mainly on the metafemoral spring, which gives to alticines the jumping ability (and the name “flea beetles”). However, Ge et al. (2011) evaluated this structure as susceptible to rapid diversification and convergent evolution. The question of whether Alticinae are a subfamily distinct from Galerucinae View in CoL within the Chrysomelidae View in CoL has been explored using morphological, molecular and larval characters with studies by Furth and Suzuki (1998), Biondi and D’Alessandro (2010), Ge et al. (2012) and Nie et al. (2020) recovering a monophyletic Alticinae , whereas Lingafelter and Konstantinov (1999), Gómez-Zurita et al.(2008), Nadein and Bezdĕk (2014), Nie et al. (2017a) and Douglas et al. (2023) recover alticines as a tribe of Galerucinae View in CoL .

Nie et al. (2017b) summarized that Galerucinae s. str. has 7,145 species (7,132 recent, 13 fossils) and 192 subspecies from 543 genera (542 recent, 1 fossil); Viswajyothi and Clark (2022) updated this number to 544 genera and 7,318 species. Galerucinae s. str. does not have cosmopolitan genera and in the Neotropical region there are 98 recorded genera – 52 of them endemic ( Viswajyothi and Clark 2022); this group consists of five tribes: Oidini, Hylaspini , Galerucini, Metacyclini and Luperini – the last three occurring in Brazil, totaling 503 species included in 58 genera. Luperini includes the most species-rich genera of the Neotropical Region: Diabrotica Chevrolat, 1836 with 370 species (138 of these occur in Brazil), Isotes Weise, 1922 with 181 species (38 Brazilian taxa), Acalymma Barber, 1947 with 72 species (13 species listed for Brazil), and Paranapiacaba Bechyně, 1958 with 58 species (20 recorded for Brazil) ( Nie et al. 2017b). The main authors that described Brazilian taxa were the same of Alticini except Gerard Scherer (see below), with addition of Frederick C. Bowditch (1853–1825), Doris H. Blake, Jan K. Bechyně and John Avery Wilcox (1921–2003). Wilcox (e.g., 1971, 1972, 1973, 1975) published the catalog of world Galerucinae s. str. species known.

The tribe Alticini comprises about 10,000 species and over 601 genera worldwide ( Douglas et al. 2023). Alticines, or flea-beetles, are mostly represented by small or medium-sized leaf beetles distributed worldwide (with exceptions of Antarctica and some oceanic islands), reaching its highest diversity in the Neotropical Region ( Damaška 2017). They are generally recognized by the enlarged hind femora containing the metafemoral spring. The adults and larvae are herbivorous, and most of them show host plant specialization being mono- or oligophagous (Jolivet 1988).

The Brazilian Alticini fauna is composed of 1,413 species across 144 genera. The main researchers on this group in Brazil were Jan Bechyně and Bohumila Bechyně whit together described 43.9% of the species and 41.1% of the Alticini genera. Hamlet Clark also was an important researcher, having described 31 genera and 246 species (17.4%). Other significant contributors include Martin Jacoby with 126 described species, Joseph S. Baly with 64 species, Edgar Harold (1830–1886) described 63 species, and Gerard Scherer (1929–2012) who described 50 species in the 1960s ( Scherer 1960), and published the only key to Neotropical Alticini genera ( Scherer 1962, 1983). These seven authors are responsible for describing 82.8% of the Brazilian Alticini fauna. The most recently described Alticini species have been discovered by sampling moss and leaf litter, habitats that had never been investigated before in Brazil ( Linzmeier and Konstantinov 2009, Oliveira et al. 2021). More recently, several studies on ecology ( Linzmeier et al. 2006, Rech and Linzmeier 2019), natural history and biology of Alticini have been published (e.g., Del-Claro 1991, Linzmeier et al. 2007, Begha et al. 2021, Antonio et al. 2022). However, much still remains to be explored for this taxon and all other chrysomelid groups.