A Survey of the Brazilian Dicranocentrus Schött (Collembola, Orchesellidae, Heteromurini) with the Description of a New Species and Notes on the Genus

Abstract

Dicranocentrus Schött is the most diverse and widespread taxon of Neotropical Orchesellidae. In Brazil, the genus is represented by 11 species found in humid forested areas of Atlantic and Amazon forests domains. Here we describe in detail Dicranocentrus abestado sp. nov. from Chapada Diamantina, Caatinga domain, Brazil. The new species belongs to the marias group sensu Mari-Mutt, due to the absence of most posterior macrochaetae on the dorsal head, and resembles other Neotropical species with 3, 2 and 2 central macrochaetae on abdominal segments I–III. However, the new species is unique especially by its reduced colour pattern combined with its empodial complex morphology. We compare Dicranocentrus abestado sp. nov. with 27 other taxa from the New and Old World, including all species with 3 macrochaetae on the first abdominal segment; provide notes and details on the morphology of the compared species plus identification keys to Brazilian and all species of the genus with similar abdominal chaetotaxy. We also discuss the current taxonomical knowledge on Brazilian Dicranocentrus and provide notes on its chaetotaxy and Heteromurinae systematics.

A mitogenomic phylogeny of the Entomobryoidea (Collembola): A comparative perspective

“…Apparently, the use of mitogenomes lacks resolution to such analysis due to their faster rate of mutation compared to nuclear genes, and so mitogenomes are more suitable to estimate a more recent evolution (Havird & Sloan, 2016). It is unlikely that the taxa considered as Heteromurinae emerged more than once within the Orchesellidae, since they share an overall reduction of trunk dorsal macrochaetae (versus polymacrochaetotic chaetotaxy among the unscaled Orchesellidae), scales (absent in the other Orchesellidae) and a reduced and stable S‐chaetotaxy formula on thorax II to abdomen III: 2, 2|1, 3, 3 (otherwise among the other Orchesellidae), with just few variations on abdomen V (Bellini et al., 2020; Nunes et al., 2020; Zhang et al., 2019, 2020). For instance, a recent molecular phylogeny showed Sinodicranocentrus , Dicranocentrus , Alloscopus and Heteromurus all related and inside Heteromurinae, data which is also in agreement with morphological evidence (Zhang et al., 2020).…”

Hexapoda Yearbook (Arthropoda: Mandibulata: Pancrustacea) Brazil 2020: the first annual production survey of new Brazilian species

“…A total of 680 new Brazilian species of Hexapoda were described in 2020, which are distributed among 245 genera, 112 families and 18 orders. These new species were published in a total of 219 papers (alencar & aZevedo 2020;almeida et al 2020aalvarado 2020;alveS et al 2020;ament et al 2020;amorim et al 2020;antuneS & takiya 2020;araujo & bravo 2020;Ávila Júnior et al 2020;baker & Haraty 2020;barboSa et al 2020;barbut 2020;barroS et al 2020abravo et al 2020;bellini et al 2020abenetti et al 2020abevilaqua & fonSeca 2020;biffi 2020biffi , biffi & GeiSer 2020braGa & ferreira-jr 2020;brown et al 2020;buSanello et al 2020;camacHo et al 2020;camarGo et al 2020;camarGoS et al 2020;camPaner & will 2020;camPoS et al 2020;caron et al 2020;carvalHo et al 2020;caSadei-ferreira et al 2020;caStro-HuertaS et al 2020;caStro-SouZa et al 2020acaterino & tiSHecHkin 2020;ceGolin et al 2020;cHaul 2020;ciPola et al 2020;clarkSon et al 2020;conStantini et al 2020;coSta et al 2020;curletti 2020;…”

The Puzzling Falcomurus Mandal (Collembola, Orchesellidae, Heteromurinae): A Review

“…The upper a5 mac marked by the author could represent the a1 mac seen in scaleless Orchesellidae, like Orchesella [ 32 ] (p. 152). However, since the a1 mic in the new species occurs near to the pseudopore, next to m1 , a feature seen in several other Heteromurini [ 3 , 8 , 27 , 33 , 34 ], we disregarded Mandal’s representation of this mac, considering it as a doubtful feature. On the Abd.…”

“…Regarding other characteristics, in Ant. IV we disregarded the presence of the antennal bulb, as noted by [ 8 ], but considered the left side structure as a pin projection (see [ 15 ] (p. 79, Figure 5) and [ 27 ] (p. 4, Figure 2B)). Mandal’s description noted his species had all legs scaled; however, the author did not remark on the presence or absence of scales on any particular segment of the legs.…”

“…The chaetotaxy terminology used in this study mainly follows Fjellberg [ 24 ] for labial palp papillae; Gisin [ 25 ] for labial chaetotaxy, with additions of Zhang and Pan [ 26 ] and using Bellini et al [ 27 ] as a model; Cipola et al [ 28 ] for labral chaetotaxy; Mari-Mutt [ 29 ] for dorsal head chaetotaxy, with additions of Soto-Adames [ 30 ] and Zhang et al [ 8 ]; Szeptycki [ 31 ] and Zhang and Deharveng [ 1 ] for S-chaetotaxy; and Szeptycki [ 32 ] for dorsal chaetotaxy, with additions and modifications provided by Soto-Adames [ 30 ], Cipola et al [ 33 ] and Zhang et al [ 3 , 8 , 34 ], using also Bellini et al [ 27 ] as a model.…”