Leucogeorgia gioi, Antić & Reip, 2020

Antić, Dragan Ž. & Reip, Hans S., 2020, The millipede genus Leucogeorgia Verhoeff, 1930 in the Caucasus, with descriptions of eleven new species, erection of a new monotypic genus and notes on the tribe Leucogeorgiini (Diplopoda: Julida: Julidae), European Journal of Taxonomy 713, pp. 1-106 : 33-37

Leucogeorgia gioi sp. nov.

urn:lsid:zoobank.org:act:A102B926-4299-4931-A6D7-F026A81CDE57

Figs 1C , 19–21 , 56 , 58

Diagnosis

This species belongs to the group of Leucogeorgia spp. without modified mouthparts and with teeth on the mesomeral claw (vs absent from L. golovatchi sp. nov., L. lobata sp. nov. and L. prometheus sp. nov.). Leucogeorgia gioi sp. nov. differs from both L. abchasica and L. satunini by having a more slender mesomeral claw with just a few teeth (vs a more robust, more or less strongly denticulate mesomeral claw in L. abchasica and L. satunini ) and a strongly serrate mesomeral lamella (vs mesomeral lamella not too strongly serrate in L. abchasica and L. satunini ). Leucogeorgia gioi sp. nov. differs from L. borealis sp. nov. and L. oculata sp. nov. by having an elongate and erect mesomeral claw with a few teeth (vs a stout mesomeral claw strongly denticulate in L. borealis sp. nov. and L. oculata sp. nov.).

Etymology

The new species is dedicated to its collector, Giorgi Gio Nebieridze from Georgia. Noun in the genitive case.

Material examined

Holotype

CENTRAL-WEST GEORGIA – Chiatura District • ♂; village Gundaeti, Sachinkia Cave ; 42.23° N, 43.32° E; 2 Mar. 2018; G. Nebieridze leg.; IZISU.

Paratypes

CENTRAL-WEST GEORGIA – Chiatura District • 1 ♂, 1 ♀, 1 juv.; same collection data as for holotype; IZISU .

Other material

CENTRAL-WEST GEORGIA – Chiatura District • 2 ♂♂, 4 ♀♀, 3 juvs; Rgani to Vachevi, Kokozouri Cave ; 42.32° N, 43.22° E; 21 Nov. 2017; G. Nebieridze and S. Barjadze leg.; IZISU • 1 ♀; same collection data as for preceding but 15 Jun. 2019; H. Reip leg.; SMNG • 1 ♂; village Sveri, Kotias Cave ; 42.21° N, 43.32° E; Nov. 2018; G. Nebieridze leg.; IZISU • 1 ♂; Shvilobisa Cave ; 42.32° N, 43.26° E; Nov. 2018; G. Nebieridze leg.; IZISU • 1 ♀; Devis Khvreli Cave ; 42.31° N, 43.24° E; Nov. 2018; G. Nebieridze leg.; IZISU .

Description

SIZE AND NUMBER OF BODY RINGS. Holotype male 22 mm long, vertical diameter of largest body ring 1.3 mm, body with 50 podous rings + 4 apodous rings + telson. Paratype male 32 mm long, vertical diameter of largest body ring 1.6 mm, body with 67 podous rings + 0 apodous rings + telson. Females 27–31 mm long, vertical diameter of largest body rings 1.4–1.7, body with 58–62 podous rings + 1–3 apodous rings + telson.

COLOUR ( Figs 1C , 19 ). Live colouration yellowish white. Greyish white in alcohol.

HEAD ( Fig. 19B ). Without ommatidia. Frontal setae absent. Labrum with three labral teeth, four supralabral setae and 18 labral setae. Gnathochilarium with rhomboid promentum; lamellae linguales with 4+4 setae in one row; stipites with 3+3 distolateral and 2+3 medial setae. Antennae 2 mm long in holotype male, their length ca 150% of vertical diameter of largest body ring. Lengths of antennomeres I–VIII (in mm): 0.14 (I), 0.43 (II), 0.34 (III), 0.34 (IV), 0.42 (V), 0.2 (VI), 0.1 (VII) and 0.03 (VIII). Length/width ratio of antennomeres I–VII: 0.9 (I), 3.3 (II), 3 (III), 2.5 (IV), 2.5 (V), 1.3 (VI) and 0.8 (VII). Antennomeres V and VI each with a terminal corolla of large sensilla basiconica bacilliformia; antennomere VII with a terminal corolla of small sensilla basiconica bacilliformia.

BODY RINGS ( Fig. 19D ). Entire metazonal area with longitudinal striations. Length of midbody setae ca 6% of vertical diameter of rings.

TELSON ( Fig. 19C ). Epiproct with a very short and blunt preanal process, covered with dorsal and lateral setae. Paraprocts rounded, with numerous setae. Hypoproct without any modifications.

LEGS IN MALES. First pair of legs modified, hook-shaped ( Fig. 21 E–F), with three podomeres; coxa with one seta; prefemur with five setae; femora, postfemora, and tibiotarsi coalesced; femur with 3–4 setae; postfemur with one seta. Tibiotarsal part with a small distal lobe (tarsal remnant). Tip tuberculated. Postfemoral and tibial ventral pads well developed on anterior legs, then gradually disappearing towards posterior legs.

PENES ( Fig. 21D ). In form of a short trapezoid, apically with two small subtriangular lobes.

VENTRAL MARGIN OF MALE BODY RING 7 ( Fig. 19E ). Well-developed, subtriangular in lateral view.

GONOPODS ( Figs 20 , 21 A–C). Promere (p) long and slender, with a flagellum (f); apical part spatulate, with denticulate margins; basal half with two developed ridges. Mesomere (m) with a slender mesomeral claw (mc) with just a few teeth; mesomeral lamella (ml) with a strongly serrate distal margin, posterior part finely fimbriate. Opisthomere (o) bipartite. Anterior branch of o with a solenomere (s) with a long tip significantly exceeding posterior part of lamella in height, and a well-developed and fimbriate velum (v). Posterior branch of o in form of a shield-like protective lamella (pl). Mesomere and opisthomere connected basally with an accessory membrane (am).

Distribution

Known only from four caves in the Chiatura district ( Fig. 58 , green triangles).

Remarks

In the Kotias Cave, this species lives in sympatry with L. longipes , which has modified mouthparts; these two species represent the southeasternmost records of the genus Leucogeorgia .

Figures

Fig. 1. Leucogeorgia Verhoeff, 1930 species in situ. A. L. abchasica (Lohmander, 1936) comb. nov., ♂ from Abraskila Cave (photo: Ilya Turbanov). B. L. caudata sp. nov., type ♂ from Novoafonskaya Cave (photo: Olga Chervyatsova). C. L. gioi sp. nov., paratype ♀ (SMNG) (photo: Hans Reip). D. L. lobata sp. nov., specimens from Motena Cave (photo: Hans Reip). E. L. prometheus sp. nov., specimen from Prometheus Cave (photo: Hans Reip). F. L. profunda sp. nov., non-type ♀ from Veryovkina Cave (photo: Sergei Ivanov). G. L. turbanovi sp. nov., non-type ♂ from Krubera Cave (photo: Ilya Turbanov).

Fig. 19. Leucogeorgia gioi sp. nov., types from Sachinkia Cave (IZISU). A. Holotype ♂, habitus, dorsal view. B. Paratype ♀, anterior part of body, lateral view. C. Holotype, posterior part of body, lateral view. D. Paratype ♂, midbody rings, lateral view. E. Paratype ♂, body ring 7, lateral view. Arrows indicate metazonal setae. Scale bars: A = 5 mm; B–E = 1 mm.

Fig. 20. Leucogeorgia gioi sp. nov., gonopods, lateral views (IZISU). A. ♂ from Kotias Cave. B. ♂ from Shvilobisa Cave.

Fig. 21. Leucogeorgia gioi sp. nov., holotype ♂ from Sachinkia Cave (IZISU). A. Right gonopods, mesal view. B. Left gonopods, lateral view. C. Left promere, lateral view. D. Penes, posterior view. E. Right leg 1, lateral view. F. Leg-pair 1, anterior view. Abbreviations: am = accessory membrane; f = flagellum; m = mesomere; mc = mesomeral claw; ml = mesomeral lamella; o = opisthomere; p = promere; pl = protective lamella; s = solenomere; v = velum. Scale bar: 0.3 mm.

Fig. 56. General distribution of the Caucasian leucogeorgiinines. The white dashed line hypothetically indicates the boundary between the northwestern and southeastern groups of species of the genus Leucogeorgia Verhoeff, 1930.

Fig. 58. Distribution of the southeastern group of the genus Leucogeorgia Verhoeff, 1930 and the species Martvilia parva gen. et sp. nov.