Micronetinae, Hull, 1920

Silva-Moreira, Thiago Da, Kulkarni, Siddharth & Hormiga, Gustavo, 2025, A total evidence phylogenetic analysis of the spider family Linyphiidae (Araneae, Araneoidea), Zootaxa 5685 (1), pp. 1-78 : 55

“ Micronetinae ”

Micronetinae Hull, 1920 was circumscribed by Saaristo &Tanasevitch (1996) and diagnosed based on their complex embolic division (which they described in detail) and the presence of the outward pointing suprategular apophysis just below the tip of the cymbium in the unexpanded palp. Among their genitalic features, micronetines have an enlarged U-shaped paracymbium, with pockets and an enlargement of the seminal duct prior to the entrance on the embolus proper (Fickert’s gland). Although these diagnostic characters were carefully described and illustrated, Saaristo & Tanasevitch (1996) did not provide a phylogenetic justification to their concept of Micronetinae .

None of our analyses support the monophyly of Micronetinae sensu Saaristo and Tanasevitch (1996) (see T able 5). In that respect, our results are consistent with previous studies (e.g., Arnedo et al. 2009; Wang et al. 2015; Zhao and Li 2017). No phylogenetic analysis with a sufficient taxon sample has ever supported the monophyly of micronetines. The “micronetine” representatives in our analyses are placed across four different lineages: Centromerus clade, Lepthyphantinae , Agyneta clade, and Microneta clade, in addition to the isolated Allomengea lineage. All those clades, except for the Microneta clade, were recovered with full support in all our large and small datasets analyses. The Centromerus clade (clade F in Wang et al. 2015) and the Lepthyphantinae (Clade A in Arnedo et al. 2009, and Clade A in Wang et al. 2015) are the first of the “micronetine branches” of Clade B ( Fig. 7 ).

Centromerus clade ( Fig. 7 )

The Centromerus clade is a small lineage composed of only three genera: Centromerus Dahl ; Saaristoa Millidge ; and Doenitzius Oi. Both Saaristoa and Doenitzius are small genera (five and two species, respectively) and (with the exception of S. sammamish (Levi & Levi)) restricted to the Palearctic and Sino-Japanese regions (sensu Holt et al. 2013). After the original descriptive work, few studies have addressed these genera. While there is no formal taxonomic revision of Centromerus , there have been occasional species transfers and nomenclatural acts concerning the species of the genus. Millidge (1977) placed Centromerus within his Lepthyphantes group based on the conformation of the seminal ducts.

Figures

FIGURE 7. Partial tree from the preferred hypothesis for linyphioids (M4_MB). Clade B (part). Turinyphia clairi, Centromerus clade, and Lepthyphantinae. Black arrow points to Wubanoides placement, Black-colored squares represent nodes with posterior probability =1; gray-colored squares represent nodes with posterior probability between 0.95 and 0.99.