On the mysterious Seychellois endemic spider genus Cenemus (Araneae, Pholcidae) Author Huber, Bernhard A. https://orcid.org/0000-0002-7566-5424 Zoological Research Museum Alexander Koenig, LIB, Bonn, Germany b.huber@leibniz-lib.de Author Meng, Guanliang https://orcid.org/0000-0002-6488-1527 Zoological Research Museum Alexander Koenig, LIB, Bonn, Germany text Arthropod Systematics & amp; Phylogeny 2023 2023-02-10 81 179 200 http://dx.doi.org/10.3897/asp.81.e86793 journal article http://dx.doi.org/10.3897/asp.81.e86793 1864-8312-81-179 17BF91115551410B97030B0F3AAE867E 1659D2F369E1554691270129ED1C2B56 3.2.1. Genus Cenemus Saaristo, 2001 (Family Pholcidae C.L. Koch, 1850) Cenemus Saaristo, 2001: 19 (type species: Holocnemus culiculus Simon, 1898). Description. The three species currently included in this genus are extremely similar to each other. The redescription of the type species below thus covers the genus except for some minor details of the genitalia (cf. Saaristo 2001 , 2002 ). Diagnosis. Large, long-legged pholcids with deep carapace pit and cylindrical abdomen; distinguished from similar Smeringopinae (especially Smeringopus ; also Holocnemus and Smeringopina Kraus, 1957) by the combination of: (1) male gonopore with six epiandrous spigots (Fig. 31 ; only two in Smeringopus and Smeringopina ); (2) ALS with only two spigots each (Fig. 63 ; seven to eight in Smeringopus and Smeringopina ); (3) male chelicerae with one pair of apophyses, each with one conical hair at tip (Fig. 33 ; two or more hairs in certain Holocnemus and other Smeringopinae ; some Smeringopinae without conical hairs); (4) male and female chelicerae with distinct stridulatory files (Figs 36 , 49 ; absent in Smeringopus and Smeringopina ); (5) palpal tarsus without macrotrichia (Figs 9-11 ; often present in Smeringopus and Smeringopina ); (6) procursus tip without ventral spine (Fig. 20 ; present in most other Smeringopinae ); (7) male anterior femora without spines (present in Holocnemus , Crossopriza , Stygopholcus , and Hoplopholcus ); (8) prolateral trichobothrium of tibia 1 absent (present in Smeringopus and Smeringopina ); (9) tarsal pseudosegments distinct (Fig. 56 ; indistinct in all other Smeringopinae ); (10) leg tarsal organs oval, with indentation in proximal median part of rim (Figs 58-61 ; round and without indentation in all other Smeringopinae ). Natural history. Nothing has been published about the biology of Cenemus before. Given the high general similarity of the three known species, the basic observations on C. culiculus below are probably valid for all of them. Relationships. Cenemus is part of the northern group of Smeringopinae . Its sister group remains unclear (see Discussion). Composition and distribution. Three species endemic to the Seychelles (Fig. 2 ): Cenemus culiculus (Simon, 1898) ( Mahe and Silhouette); C. silhouette Saaristo, 2001 (Silhouette); and C. mikehilli Saaristo, 2002 (La Digue and Marianne). All available evidence suggests that Cenemus is indeed restricted to the Granitic Seychelles. Given the size of the spider and the easily visible large webs, it seems very unlikely that Cenemus has been overlooked in other regions. Figure 2. Known distributions of the northern and southern groups of Smeringopinae and of Cenemus . Excluded from this map are three widely distributed synanthropic species: Holocnemus pluchei (Scopoli, 1763); Crossopriza lyoni (Blackwall, 1867); and Smeringopus pallidus (Blackwall, 1858). Also excluded are Australian records of Smeringopus natalensis Lawrence, 1947. Note that the southern group ranges into the southern Arabian Peninsula but the respective blue dots are covered by orange dots. Figures 3-4. Typical habitat of Cenemus culiculus (Simon, 1898) on Mahe , Casse Dent (arrow points at preferred microhabitat of adults), and web of C. culiculus ( Mahe , Bel Ombre).