Eurygeophilus Verhoeff, 1899

Bonato, Lucio, Barber, Anthony & Minelli, Alessandro, 2006, The European centipedes hitherto referred to Eurygeophilus, Mesogeophilus, and Chalandea (Chilopoda, Geophilomorpha): taxonomy, distribution, and geographical variation in segment number, Journal of Natural History 40 (7 - 8), pp. 415-438 : 417-419

Eurygeophilus Verhoeff, 1899

Geophilus (Eurygeophilus) Verhoeff, 1899

5 Geophilus (Mesogeophilus) Verhoeff, 1901 (n. syn.)

5 Chalandea Brölemann, 1909 (n. syn.)

Geophilus (Eurygeophilus) Verhoeff 1899, p 366 (original description); 1901a, p 418; 1902– 25, p 284 (diagnosis), 285, 295, 581 (in key); 1928, p 267 (in key); Attems 1903, p 170, 217 (in key), 240 (diagnosis).

Eurygeophilus: Attems 1926, p 328 , 359, 361 (in key); 1929, p 211 (diagnosis); 1947, p 107 (in key); Brolemann 1926b, p 233, 236; 1930, p 35, 52, 186, 187 (diagnosis), 190; Verhoeff 1938, p 346, 351; 1940, p 19; Eason 1951, p 264; Machado 1952, p 84; 1953, p 82; Demange 1981, p 212.

Geophilus (Mesogeophilus) Verhoeff 1901b, p 681 (original description); 1902–25, p 284 (diagnosis), 285, 295, 580 (in key); 1928, p 266 (in key); 1938, p 346; 1941, p 89; Attems 1903, p 170, 217 (in key), 240 (diagnosis).

Mesogeophilus: Attems 1929, p 159 (in key), 194 (diagnosis, key to species); 1947, p 109 (in key), 124; Minelli 1978, p 158; Foddai et al. 1995, p 31 (validity doubted); Turcato et al. 1995, p 198, 208; Pereira et al. 1997, p 79.

Not Mesogeophilus: Attems 1938, p 191 ; Shinohara 1999, p 698 (in key), 707.

Chalandea Brölemann 1909a, p 330 , 331, 338 (original description); 1930, p 35, 52, 186, 190 (diagnosis); Attems 1926, p 260, 359, 361 (in key); 1929, p 210 (diagnosis); 1947, p 107 (in key), 127 (key to species); 1952a, p 50 (also Chalandes [sic] on p 50); Verhoeff 1938, p 352 (diagnosis); 1940, p 19; 1943, p 5; Würmli 1972, p 4; Minelli 1978, p 158; 1992, p 170, 188; Demange 1981, p 212; Minelli and Zapparoli 1985, p 381; Koren 1986, p 36 (diagnosis); Salinas 1990, p 3; Foddai et al. 1995, p 10, 31; Turcato et al. 1995, p 198, 208.

Geophilus (Chalandea) : Verhoeff 1902 –25, p 581.

Diagnosis

Head shield convex, slightly wider than long; lateral margins distinctly curved, convergent anteriorly; posterior margin truncate, slightly concave; no frontal line. Antennae 2.2–3.6 times as long as the head width. Clypeus with a pair of non-areolate semicircular areas along the posterior margin. Labrum mid-part with a few round-tipped teeth; side-pieces well delimited, each bearing a fringe of slender projections. Mandibles and maxillae as typical of geophilids; two pairs of lateral lappets on the first maxillae; claw of the second maxillae quite long but round-tipped. Forcipular segment stout; coxosternum two to three times wider than long, with lateral margins sinuous, without distinct chitin-lines; forcipular tergum with lateral margins convergent anteriorly, only slightly narrower than the following tergum; no teeth on the internal side of forcipules; basal article of forcipules shorter than wide; tarsungulum strongly narrowed close to the base, slender and flattened. Sternal pores in a narrow transverse band on the posterior part of each sternum from the first to the penultimate leg-bearing segment; no median sockets on the anterior margin of sterna. Praetergum of last leg-bearing segment not separated from pleurites. Last pair of legs distinctly swollen and bearing additional dense setae on the ventral side in the male, slender and without additional setae in the females; claw present. Gonopods as typical of geophilids.

Type species. Geophilus (Eurygeophilus) multistiliger Verhoeff, 1899 by monotypy.

Included species. Eurygeophilus multistiliger ( Verhoeff, 1899) ; Eurygeophilus pinguis (Brölemann, 1898) (n. comb.).

Taxonomic and nomenclatural remarks

Mesogeophilus was described by Verhoeff (1901b) as a subgenus of Geophilus to include the only species Geophilus (Mesogeophilus) baldensis Verhoeff, 1901 , which is its type species by monotypy. Mesogeophilus was then elevated to genus rank by Attems (1929), followed by most other authors, but the diagnosis of this nominal genus remained very vague indeed (Minelli 1992; Foddai et al. 1995). Mesogeophilus Verhoeff, 1901 is here synonymised with Eurygeophilus Verhoeff, 1899 since we recognize the type species of the former as a junior synonym of Geophilus pinguis Brölemann, 1898 (see remarks under E. pinguis ) and we include this latter species in the genus Eurygeophilus (see below).

Chalandea was described by Brölemann (1909a) to include only the species Geophilus pinguis Brölemann, 1898 , which is its type species by monotypy. Chalandea was regarded as a genus by most authors; only Verhoeff treated it as a subgenus of Geophilus in one of his major works ( Verhoeff 1902 –25). Chalandea Brölemann, 1909 is here synonymised with Eurygeophilus Verhoeff, 1899 because the type species of both nominal taxa share some major characters which differentiate them from all other geophilids such as to justify their inclusion in the same genus. Among these characters are the general body shape and the unusual shape of the forcipular segment. Despite the fact that the phylogenetic relationships within the geophilids are still unresolved ( Foddai and Minelli 1999, 2000; Edgecombe and Giribet 2004) and thus the current taxonomic arrangement of this group remains in need of a thorough revision, some of the peculiar characters shared by these two species are very probably synapomorphic. All previous authors had indeed acknowledged that Eurygeophilus and Chalandea are closely related: Attems assigned G. pinguis to the subgenus Eurygeophilus in one of his earliest papers ( Attems 1903) and Brolemann (1930) introduced the tribe Eurygeophilini to include Eurygeophilus and Chalandea .

Published diagnoses of Chalandea and Mesogeophilus are widely congruent, only differing in respect to the chitin-lines, which have been described as present and complete in the type species of Chalandea ( Brölemann 1909a, 1930), absent in Mesogeophilus ( Verhoeff 1901b, 1902 –25). This putative difference has been reported uncritically by subsequent authors (e.g. Attems 1929) even though some inconsistency has been highlighted ( Verhoeff 1938; Koren 1986). Attems (1929, 1947) indeed introduced another putative difference in relation to the trunk sterna, which he described as provided with tubercles in Chalandea but lacking any tubercle in Mesogeophilus . However, our examination of specimens from throughout the geographic range of E. pinguis , including some representing G. (M.) baldensis , revealed that chitin-lines are invariantly weakly evident and the sternal tubercles invariantly present (see also remarks under E. pinguis ). Attems (1929, 1947) also considered Chalandea as having anterior sternal sockets, but we did not find such sockets in any specimen.

According to the diagnoses of Eurygeophilus previously published ( Verhoeff 1899, 1902 – 25; Attems 1903, 1929; Brolemann 1930), the poison calyx is characteristically composed of an anterior swollen part and a posterior slender part and the forcipular coxosternum is provided with shortened chitin-lines. However, direct examination of the holotype of G. (E.) multistiliger has revealed that these diagnoses were incorrect in respect of both points (see remarks under E. multistiliger ). Chitin-lines, in particular, are only weakly marked and their appearance is therefore similar to what is observed in E. pinguis ( Figure 3 ).

Three other species were included in Mesogeophilus by Attems (1929), namely Zelanophilus wheeleri Chamberlin, 1920 , Zelanophilus kapiti Archey, 1922 , and Geophilus monoporus Takakuwa, 1934 . A further species was described by Attems (1947) under this genus, namely Mesogeophilus plusioporus Attems, 1947 . In a later paper ( Attems 1959), two other species are apparently moved to Mesogeophilus , namely Geophilus ormanyensis Attems, 1903 and Geophilus xylophagus Attems, 1903 , but this was probably only a misprint for Nesogeophilus Verhoeff, 1924 . In any case, all these six species are obviously unrelated to G. (M.) baldensis and thus have to be removed from Mesogeophilus as has already been observed ( Foddai et al. 1995; Pereira et al. 1997). Zelanophilus Chamberlin, 1920 was considered a synonym of Geophilus (Mesogeophilus) Verhoeff, 1901 by Attems (1929), but we reject this opinion since the type species of the two taxa, namely Zelanophilus wheeleri Chamberlin, 1920 and Geophilus (Mesogeophilus) baldensis Verhoeff, 1901 , are obviously unrelated.

Figures

Figures 1–4. (1–3) Eurygeophilus pinguis (Brölemann, 1898), female, 33 mm long, M. La Marzola (near Trento, Alps). (1) Distal articles of the left antenna, ventral. (2) Left claw of the second maxillae, ventral. (3) Right part of the forcipular coxosternum, ventral. (4) Geophilus linearis C. L. Koch, 1835, male, 34 mm long, Cologna Veneta (near Verona, Italy): right part of the forcipular coxosternum, ventral. Arrows indicate the putative position of the forcipular chitin-lines. Micrographs from ESEM Philips XL30. Scale bars: 20 Mm (1, 2); 50 Mm (3, 4).