Species diversity of Strigamia Gray, 1843 (Chilopoda: Linotaeniidae): a preliminary synthesis

Abstract

The centipede genus Strigamia Gray (Chilopoda: Geophilomorpha: Linotaeniidae) is revised with regards to morphological diagnosis, composition in known species, taxonomic nomenclature, major characters differentiating species, and geographical distribution. Published information has been integrated and reinterpreted after direct examination of more than half of the known species. The genus Strigamia is distinguished from similar genera (Agathothus Bollman, Araucania Chamberlin, Damothus Chamberlin, Zantaenia Chamberlin) mainly by the conspicuous basal denticle of the forcipular tarsungulum, the paired ventral pore areas on the posterior part of trunk segments, and the remarkably swollen ultimate pair of legs in adult males. At least 32 distinct species are known and another 12 are recognized provisionally, whereas 21 names are rejected as synonyms. Of all other nominal species that have been referred to Strigamia or its synonyms in the past, 16 are shown not to actually belong to Strigamia and another 4 remain uncertain as to their generic assignment. Species of Strigamia differ mainly in the shape of the forcipular tarsungulum and denticle, average number of legs (overall range from 31 to 83 pairs, possibly to 91), aspect of pleuropretergite and shape of metasternite of the ultimate leg-bearing segment, and the arrangement of coxal pores. Strigamia as a whole inhabits the most part of the temperate Holarctic, but reaches southwards to the Indochinese region. The following new synonymies are introduced:

The first geophilid centipedes from Malesia: a new genus with two new species from Sumatra (Chilopoda, Geophilidae)

“…Around Sumatra, the closest undisputable records of Geophilidae are from the Himalayas ( Geophilus intermissus Silvestri, 1935) and from Bismark and Solomon Islands ( Tuoba sydneyensis (Pocock, 1891)) (Silvestri 1935, 1936, Jones 1998). However, records of Linotaeniidae, which are morphologically distinct but most probably derived within the Geophilidae (Bonato et al 2014), are known from northern Laos and Vietnam (species of Strigamia Gray, 1843; Attems 1953, Bonato et al 2012, Maruzzo and Bonato 2014) and apparently also from Java ( Javaenia bataviana Chamberlin, 1944; Chamberlin 1944; Würmli 1972). …”

Millipede and centipede assemblages on the northern and southern slopes of the lowland Altais, southwestern Siberia, Russia (Diplopoda, Chilopoda)

“…It has been doubtfully reported from Sakhalin (Russia), Japan and Taiwan (Bonato et al 2012) and recently found in the Rostov-on-Don Area, south of European Russia (Zuev and Evsyukov 2016). …”

“…Central-Palearctic temperate range: widespread from Central Europe and the Caucasus, S. pusilla is found in the Urals, SW and central Siberia and N Mongolia (Bonato et al 2012; Poloczek et al 2016; Nefediev et al 2017c, d). …”

Evolution of Strigamia centipedes (Chilopoda): a first molecular assessment of phylogeny and divergence times

“…At least 30 morphologically distinct species are known within Strigamia (Bonato et al . ). Most of these species inhabit North America, Europe and nearby Western Asia, whereas only seven species have been described from Eastern Asia, besides another four nominal taxa of uncertain validity (Murakami ; Shinohara ).…”

“…Indeed, phylogenetic inference from morphology is discouraged by the fact that all species of Strigamia are very similar and they are usually distinguished only for very few anatomical characters: above all, the number of body segments (Bonato et al . ), the shape of the so‐called forcipules (i.e. the poison fangs; Maruzzo & Bonato ) and the arrangement of the so‐called coxal organs (i.e.…”