Geophilus pygmaeus Latzel, 1880

Peretti, Emiliano & Bonato, Lucio, 2016, Geophilus pygmaeus (Chilopoda: Geophilidae): clarifying morphology, variation and geographic distribution, Zootaxa 4139 (4), pp. 499-514 : 500-510

Geophilus pygmaeus Latzel, 1880

Figs 1 , 2

Geophilus pygmaeus Latzel 1880: 182 , fig. 65; 1885: 39. Haase 1881: 83.? Daday 1889: 87. Attems 1895: 165; 1903: 222; 1926: 245, 343; 1929a: 174; 1929b: 280, 285, 287, 297; 1947: 111;? 1949: 86, 108; 1954: 292; 1959: 308. Verhoeff 1895: 353; 1896: 87; 1906: 207; 1908: 297; 1925: 618, 632, 634, 659;? 1934a: 116; 1938: 348.? Kimakowicz 1897: 99. Lucas 1898: 1062.? Diem 1903: 342.? Lignau 1905: 198. Depoli 1907: 87. Brolemann 1930: 34, 180. Schubart 1934: 80. Takakuwa 1940: 3. Folkmanová 1952: 182. Dobroruka 1961: 35. Matic 1966: 13. Würmli 1972: 3. Minelli 1978a: 303; 1981: 90; 1982: 133; 1992: 169. Koren 1986: 25; 1999: 520. Minelli & Iovane 1987: 24, 31. Zapparoli 1989: 560, 579, 580, 581. Kos 1992a: 355; 1992b: 139; 1996a: 639; 1996b: 148.? Minelli & Zapparoli, 1992: 227. Foddai et al. 1995: 10. Christian 1996: 110. Stoev 1997: 103.? Wytwer 1997: 265, 267;? 2008: 331, 333.? Simaiakis et al. 2004: 403.? Spelda 2005: 104.? Tuf & Laška 2005: 149. Iorio & Berg 2007: 35.? Tuf & Tufová 2008: 38. Geoffroy & Iorio 2009: 689. Ilie et al. 2009: 8. Stöckli 2009: 651. Danyi 2010: 20. Voigtländer et al. 2011: 104. Reip et al. 2012: 52, 55, 62, 78. Iorio 2014: 50. Bonato & Minelli 2014: 11, 33, 38, 39, 40, 45, 47, 86, 114. Moretto et al. 2015: 3.

Geophilus pusillus pygmaeus— Verhoeff 1898: 346; 1902: 91.? Vališ 1902: 23;? 1904: 5.

Geophilus larii Verhoeff 1934b: 14 . Minelli 1978b: 157. Moritz & Fischer 1979: 345. Synonymy by Verhoeff (1938: 348).

Geophilus pygmaeus pygmaeus— Kaczmarek 1980: 21.

Geophilus cf. larii— Grgič & Kos 2003: 240.

non Geophilus pygmaeus var. silesiacus Haase 1881: 83 .

non Geophilus pygmaeus styricus Verhoeff 1895: 353 ; 1896: 87. Lucas 1898: 1062. Attems 1929a: 174. Moritz & Fischer 1979: 350. Kos 1992b: 139.

non Geophilus pygmaeus— Attems 1902: 572. Verhoeff 1940: 8.

Type localities. Two localities: Trnovski gozd (= Trnovo Forest Plateau), Slovenia ; an uncertain locality in Carinthia, probably Loiblthal, Austria .

The first type locality is indicated both in the original description ( Latzel 1880: "Tarnowaner Wald bei Görz" = Trnovo Forest Plateau, near Gorica; also reported as "Küstenlande" = Eastern Adriatic coastal region) and in the label associated with two syntypes (“Tarnowaner Wald”). The second type locality is indicated in the original description ( Latzel 1880) only as " Kärnten " (= Carinthia), but a single locality "Loiblthal" is indicated by the same author when treating the fauna of Carinthia ( Latzel 1885).

Type material. A total of 18 syntypes were mentioned in the original description ( Latzel 1880), including 6 adults of both sexes and 12 juveniles reported to have been found together with a female of Dicellophilus carniolensis (C.L. Koch) . As far as we know, only 2 of the adults, one male and one female, are still in existence, in the Naturhistorisches Museum of Vienna ( Ilie et al. 2009).

Specimens examined. Syntype: ♀, 15.3 mm long, with 43 leg-bearing segments; Trnovski gozd, northern Dinarides; date and collector unknown; in ethanol, not dissected; NHMW 262 .

Specimens of a representative population: 43 specimens of both sexes, 4.8–19.3 mm long, with 41–45 legbearing segments; Ponte dei Ross, Val del Grisol, Zoldo Dolomites (46.26024°N; 12.20623°E); 5 Jun.–25 Sept. 2015, leg. E. Peretti; in ethanol, some of them dissected; PD5350, 5353, 5360, 5361, 5364, 5369, 5377, 5379, 5394, 5395, 5410, 5444–5446, 5448, 5451, 5453, 5454, 5456, 5482–5490, 5492, 5494, 5495, 5498, 5552, 5553, 5555, 5559–5561, 5564–5566, 5571, 5911.

Other specimens from other localities: see Table 1.

Diagnosis. A Geophilus species less than 20 mm long; usually 43 or 45 pairs of legs in the female, 41 or 43 pairs of legs in the male; head slightly longer than wide (length/width = ca. 1.1); antennae ca. 2 times as long as the head; no distinct clypeal areas; pretarsus of second maxillae subconic, curved, apically pointed (length/width = ca. 3); forcipular coxosternite relatively long (length/width of the exposed part = ca. 0.8); coxopleural sutures distinctly diverging forwards for the entire length; chitin-lines incomplete and pointing lateral to the condyles; basal denticle on the tarsungulum distinctly straight and pointed, about as long as wide; pore-fields well developed only in the anterior part of the trunk; carpophagus pits present; ultimate leg-bearing segment with entire pleuropretergite; in the adult, coxopleuron with usually 3 ventral pores opening separately, close to the margin of the metasternite, and a single smaller and isolated pore in the middle of the coxopleuron, positioned anteriorly with respect to the most posterior of the other pores; legs of the ultimate pair with well-developed curved claws.

Among the other species of Geophilus living in Europe ( Bonato & Minelli 2014), G. pygmaeus most closely resembles G. flavus , from which it differs mainly in some features of the antennae, the trunk metasternites and the coxal pores ( Table 2 ).

Adult female morphology. Description of an adult female (PD5451). See also Figs 1A–C , 2A–C .

GENERAL FEATURES. Body relatively stout, ca. 12.7 mm long, reaching a maximum width of ca. 0.7 mm in legbearing segments 18–23, only slightly narrowing anteriorly and posteriorly, the first leg-bearing segment being ca. 0.5 mm and the ultimate ca. 0.3 mm wide. Most legs uniformly ca. 0.5 mm long, those of the most anterior pairs decreasing gradually anteriorly, the legs of the first pair being ca. 0.3 mm long. Color (in ethanol) almost uniformly brownish-yellow, only the forcipular segment and the head slightly darker.

CEPHALIC CAPSULE. Cephalic plate subrectangular, ca. 1.1 times as long as wide, ca. 0.9 times as wide as the forcipular tergite, the lateral margins moderately convex; frontal line absent. Clypeus uniformly areolate, without clypeal areas and without plagulae; lateral margins complete; a total of 8 setae on the antero-medial part, arranged in 1 anterior pair, 1 intermediate pair, 2 posterior pairs in a transverse row. Labrum bearing two medial short tubercles distinctly sclerotized and lateral rows of bristles.

ANTENNAE. Ca. 2.0 times as long as the head. Intermediate articles up to ca. 1.2 times as long as wide. Article XIV ca. 2.2 times as long as wide, ca. 2.3 times as long as article XIII. Apical sensilla ca. 12–15 µm long, spearlike, without projections, only gently narrowing at about the mid-length. Club-like sensilla ca. 10 µm long, only on article XIV, grouped on the distal parts of both the internal and external sides. A single sensillum, similar to the apical ones, shorter than 10 µm long, close to the distal margin of articles V, IX and XIII, on both the dorso-external and the ventro-internal sides.

MANDIBLES. A single pectinate lamella on each mandible.

TABLE]. Publisheđ anđ new recorđs of Geophilus pygmaeus , incluđing publisheđ recorđs that we consiđeređ uncertain. The localities are orđeređ approximately West to East. Reasons for uncertainty: đoubt. = đoubts on the species iđentity were expresseđ by the same author/s; geogr. = the locality is outsiđe the known range of G. pygmaeus as đocumenteđ by other reliable recorđs, anđ no information is given in support of the species iđentity (criteria, sources anđ characters consiđeređ for iđentification); taxon. = the taxonomic concept of G. pygmaeus followeđ by the author/s was broađer than reviseđ here, encompassing possibly other species.

……continued on the next page TABLE]. (Continueđ) TABLE]. (Continueđ)

code locality published source examined reliability reasons for uncertainty

specimen/s

51 ̎ Steiermark: Bachern bei Marburg̎ = Pohorje near Maribor Attems 1895: 165 - yes - ( Slovenia)

52 ̎Zảgrảb̎ = Zagreb (Croatia) Dađay 1889: 87 - uncertain geogr., taxon.

53 ̎okolo boskovského [...] Pođ hrađem̎ = nearby the castle of Vališ 1902: 23 (as G. - uncertain geogr. Boskovice ( Czech Republic); also reporteđ by Vališ (1904) as pusillus pygmaeus )

̎Boskovicich̎ = Boskovice.

54 ̎Simonfa̎ (Hungary); also reporteđ by Attems (1929a) as Dađay 1889: 87 - uncertain geogr., taxon. ̎Somogy̎ = Somogy County

55 ̎Simontornya̎ (Hungary); also reporteđ by Attems (1929a) as Dađay 1889: 87 - uncertain geogr., taxon. ̎Tolna̎ = Tolna County

56 ̎Szerencs̎ ( Hungary); also reporteđ by Attems (1929a) as Dađay 1889: 87 - uncertain geogr., taxon. ̎Comitaten Zemplén̎ = Borsođ-Abaủj-Zemplén County

57 ̎K.-Azar̎ = Malé Ozorovce ( Slovakia) Dađay 1889: 87 - uncertain geogr., taxon.

58 ̎Czéke̎= Cejkov (Slovakia) Dađay 1889: 87 - uncertain geogr., taxon.

59 ̎Nagy-Mihảly̎ = Michalovce (Slovakia) Dađay 1889: 87 - uncertain geogr., taxon.

60 ̎Peér̎ = Pir (Romania); also reporteđ by Attems (1929a) as Dađay 1889: 87 - uncertain đoubt., geogr., taxon. ̎Szilagy̎ = Satu Mare

61 ̎Irakleio: Agia Eirini̎ = Heraklion: Agia Irini [Ηρόκλειο: Αγία Simaiakis et al. 2004: 403 - uncertain geogr. Ειρήνη], in Crete (Greece)

- ̎SO - Alpen̎ = South-Eastern Alps; also reporteđ by Moritz & Verhoeff 1934b: 14 (as G. - yes - Fischer (1979) as ̎ Friaul ̎ = Friuli ( Italy) larii )

- ̎ganzen Süđostalpen vom Brescianergebiet im Westen bis nach Verhoeff 1938: 348 - yes - Krain im Osten̎ = entire South-Eastern Alps between the

surrounđings of Brescia in the West anđ the Carniola in the East

(Italy, Austria, Slovenia)

- ̎alle spalle đi Vittorio Veneto (Treviso)̎ = north of Vittorio Minelli 1982: 133 PD5923 anđ others yes - Veneto ( Italy)

- ̎ Istria ̎ ( Slovenia or Croatia) Depoli 1907: 87 - yes -

- ̎ Krim ̎ = Crimea ( Ukraine) Lignau 1905: 198 - uncertain đoubt.

FIRST MAXILLAE. Coxosternite entire, without mid-longitudinal sulcus, without setae. Coxal projection subtriangular, longer than wide. Telopodite composed of two articles, the basal one without setae, the distal one with 2–3 setae and ca. 2 spine-like sensilla. Coxosternal lappets short, telopodital lappets elongate.

SECOND MAXILLAE. Coxosternite entire; anterior margin widely concave; no sclerotized ridges; some small setae close to the anterior margin. Telopodite composed of three articles, slightly narrowing towards the tip; pretarsus in shape of a long claw, ca. 3 times as long as wide, subconic, only slightly bent towards the tip, and with a small dorsal bulge close to the tip.

FORCIPULAR SEGMENT. Tergite subtrapezoid, with lateral margins evidently converging anteriorly, ca. 2.2 times as wide as long, posteriorly almost as wide as the subsequent metatergite. Exposed part of the coxosternite ca. 1.2–1.3 times as wide as long, without denticles; coxopleural sutures complete, entirely ventral, only slightly sinuous; chitin-lines incomplete and pointing lateral to the condyles. Trochanteroprefemur ca. 1.1 times as long as wide, without denticles. Intermediate articles distinct, without denticles, each with a shallow bulge only. Tarsungulum 2.8–2.9 times as long as wide, uniformly curved both internally and externally; a basal subconic tubercle, about as long as wide at the basis, distinctly straight and pointed; internal margin not crenulate. Poison calyx subspherical, between the trochanteroprefemur and the first intermediate article.

LEG- BEARING SEGMENTS. A total of 45 leg-bearing segments. Metasternites of the anterior third of the trunk distinctly wider than long, the remaining metasternites at least as long as wide. Metasternites of some anterior segments with a very shallow, bilobed socket ( carpophagus pit) on the anterior margin, particularly evident in metasternites 7–12, ca. 0.7 times as wide as the margin of the metasternite. Pore fields well developed only on the metasternites 1–14, where they resemble a transverse band, close to the posterior margin of the metasternite. Leg claws simple, uniformly bent; a pair of accessory spines, reaching approximately one third of the length of the pretarsus, the anterior spine slightly longer than the posterior one.

ULTIMATE LEG- BEARING SEGMENT. Pleuropretergite entire, lacking sutures or sulci or notches. Metasternite subtrapezoid, ca. 1.3–1.4 times as wide as long, anteriorly ca. 1.6–1.7 times as wide as posteriorly, lateral margins slightly convex, posterior margin almost straight; only 4 long setae and some additionally shorter setae. Coxal organs opening through 4 independent pores on the ventral side of each coxopleuron: 3 pores aligned along the lateral margin of the metasternite and covered by the latter; a distinctly smaller pore isolated approximately in the central part of the coxopleuron, anteriorly with respect to the most posterior of the other pores. Another coxal organ opens at the anterior tip of the coxopleuron, hardly detectable. On the left coxopleuron only, a smaller additional pore is present, close to the most anterior pore. Telopodite ca. 9 times as long as wide, ca. 1.4–1.5 times as long and 1.3 times as wide as the penultimate telopodite; 6 articles, covered with sparse long setae and rare ventral shorter setae. Pretarsus in shape of a pointed claw, similar to that of the preceding legs but slightly shorter and less sclerotized, with two accessory spines.

POSTPEDAL SEGMENTS. Genital pleurosternite entire. Gonopods in shape of a short lamina. Anal pores exposed.

Adult male morphology. Description of an adult male (PD5566). See also Fig. 1 D.

Same as the female, to the exclusion of the following characters.

GENERAL FEATURES. Body 9.1 mm long.

LEG- BEARING SEGMENTS. A total of 43 leg-bearing segments. Carpophagus pits weakly evident, on metasternites 6–10.

ULTIMATE LEG- BEARING SEGMENT. Coxal pores like in the female specimen, but no additional coxal organs detected at the tips of the coxopleura and without any unilateral pore. Telopodite ca. 6 times as long as wide, ca. 1.6 times as wide as the penultimate. In addition to sparse long setae, many distinctly denser and shorter setae on the ventral side of the most posterior part of the coxopleuron and of all the articles of the telopodite.

POSTPEDAL SEGMENTS. Complete sutures between the genital sternite and the pleurites, converging anteriorly. Gonopods biarticulated, well separated, covered with setae, with a subconic penis in between.

Variability between individuals. Variation in a representative population (n=43).

GENERAL FEATURES. Maximum body length in females 19.3 mm, in males 13.4 mm.

LEG- BEARING SEGMENTS. Number of leg-bearing segments in females 43 or 45, more frequently 45 (84%, n=19), in males 41 or 43 or 45, more frequently 43 (87%, n=15).

ULTIMATE LEG- BEARING SEGMENT. Number of coxal pores increasing with body size, through at least three recognizable conditions ( Fig. 3 ):

(i) a single pore approximately in the middle of the ventral surface of each coxopleuron. This condition was found in specimens up to 5.6 mm long, all without gonopods;

(ii) 3 pores on each coxopleuron: 2 pores along the lateral margin of the metasternite, similar in size; another pore more external, about halfway between the other pores, similar in size or slightly smaller than the other pores. This condition was found in specimens 5.5–5.9 mm long, either without gonopods or with female gonopod anlagen;

(iii) 4–5 (occasionally 6) pores on each coxopleuron: 3 larger pores approximately aligned along the lateral margin of the metasternite, the most anterior pore often covered by the presternite and sometimes difficult to detect; a smaller pore more external, anteriorly with respect to the most posterior of the other pores; sometimes another pore on the tip on the coxopleuron; rarely, an additional smaller anterior pore. This condition was found in specimens more than 6.4 mm long, with partially or fully developed gonopods. The additional pore on the tip of the coxopleuron was detected on both sides in 6 specimens and at least on one side in another 2 specimens, whereas it was apparently absent in another 23 specimens, but it was not possible to rule out the presence of hidden pores.

POSTPEDAL SEGMENTS. Among females, the gonopodal lamina was detected in all and only the specimens longer than 6.7 mm. Among males, at least partially developed gonopods were found in all specimens longer than 6.4 mm and fully developed gonopods in all specimens longer than 7.5 mm.

Geographical distribution. Based on all reliable published records and new records obtained from specimens directly examined by us (Table 1; Fig. 4 ), the presence of G. pygmaeus resulted well documented in the South– Eastern Alps, at least between the Como Lake in the West and the Slovene Prealps in the East, and in the most northern reaches of the Dinarides. In particular, populations of G. pygmaeus were ascertained in all the following sections of the Alps (as defined in the SOIUSA; Marazzi 2005): Bergamasque Alps and Prealps, Southern Rhaetian Alps, Brescia and Garda Prealps, Venetian Prealps, Dolomites, Carnic and Gailtal Alps, Julian Alps and Prealps, Carinthian–Slovenian Alps and Slovene Prealps. Most records are from the most marginal mountain massifs and plateaus, with a few records in some inner part of the Alps (Val di Tovel, code 18, Mt. Antelao, 27; Fig. 4 ).

Published records of G. pygmaeus exist also for a couple of more western localities along the Prealps (codes 1, 2) and a few more northern localities in the Alps (7, 26, 43), but they need confirmation (Table 1). Other putative records of the species have been reported for other regions North and East of the Alps, i.e. either the Lower Bavarian Hills or the Bavarian Forest (38), the Drahany Highlands in Moravia (53), the area between the northern Dinarides and the Transdanubian Hills (52, 54, 55) and the Western Carpathians (56–60), but they all date before the mid-20th century and have not been confirmed more recently (Table 1). G. pygmaeus has also been reported twice for Crete, first by Attems (1902) and more recently by Simaiakis et al. (2004), but probably because of the misidentification of a similar species (Table1; see also Discussion).

Figures

FIGURE 3. Relation between the number of coxal pores and the maximum width of the metasternite of the ultimate legbearing segment, taken as a proxy of body size, in a single population of Geophilus pygmaeus (n = 43). The size of the symbols is proportional to the number of specimens. The icons represent the ventral arrangement of the coxal pores.

FIGURE 4. Geographical distribution of Geophilus pygmaeus. A. General distribution in Europe. B. Detailed distribution in the Alps and northern Dinarides. Codes refer to Table 1. Records from imprecisely defined localities are not mapped. Background of panel A from Earthstar Geographics SIO. Background of panel B from SRTM.

FIGURE 1. A – C. Geophilus pygmaeus, adult ♀ (PD 5451). A. Head without antennae, ventral view; areolation partially omitted. B. Forcipular segment, ventral view; photo (left) and interpretative drawing (right); setae omitted. C. Ultimate legbearing segment and postpedal segments, ventral view. D. Geophilus pygmaeus, adult Ƌ (PD 5566): ultimate leg-bearing segment and postpedal segments, ventral view.

FIGURE 2. A – C. Geophilus pygmaeus, adult ♀ (PD 5451). A. Head without left antenna, dorsal view. B. Leg-bearing segment 10, ventral view. C. Ultimate leg-bearing segment and postpedal segments, without ultimate legs, ventral view. D – E. Geophilus pygmaeus, syntype, ♀ (NHMW 262). D. Forcipular segment, ventral view. E. Ultimate leg-bearing segment and postpedal segments, without ultimate legs, ventral view.

Tables

TABLE 2. Major differential characters between Geophilus pygmaeus and G. flavus. Published data on G. flavus (e. g., Brolemann 1930, Barber 2009) were integrated through the direct examination of representative specimens.

character	G. pygmaeus	G. flavus
Body: maximum length	20 mm	45 mm
Body: length/width	ca. 18	ca. 30
Antenna/head length	ca. 2	ca. 5
Antenna: intermediate articles: length/width	<1.2	> 1.5
Clypeal area: presence	no	yes
Coxopleural sutures: relative position	distinctly diverging also in the anterior part	about subparallel in their anterior part
Leg-bearing segments: number	♀ 43–45, rarely 47 Ƌ 41–43, rarely 45	♀ 49–57, rarely 4 7–59 Ƌ 45–57, rarely 43
Carpophagus pits: presence	yes	no
Coxopleuron (adult): smaller isolated pore in the middle of the ventral side: presence	yes	no