Plutomurus jordanai Barjadze & Soto-Adames, 2020

Barjadze, Shalva, Giordano, Rosanna & Soto-Adames, Felipe, 2020, Description of a new species of Plutomurus Yosii (Collembola: Tomoceridae) from Georgia, Caucasus and notes on the morphology of Plutomurus birsteini Djanashvili & Barjadze, Zootaxa 4790 (2), pp. 375-386 : 377-383

publication ID	https://doi.org/ 10.11646/zootaxa.4790.2.11
publication LSID	lsid:zoobank.org:pub:4D7A9C7C-AAD3-4C2B-8A46-A7AB229D13B0
DOI	https://doi.org/10.5281/zenodo.10564116
persistent identifier	https://treatment.plazi.org/id/5630E96F-FFD0-FFA8-04DA-F97CFE510B82
treatment provided by	Plazi
scientific name	Plutomurus jordanai Barjadze & Soto-Adames
status	sp. nov.

Treatment

Plutomurus jordanai Barjadze & Soto-Adames sp. nov.

( Figs 4–19 View FIGURE 4 View FIGURES 5–6 View FIGURES 7–9 View FIGURE 10 View FIGURE 11–18 View FIGURES 19–20 )

Type locality. GEORGIA, Imereti region, Tskaltubo district, near Zeda Kvilishori village, Sataplia-Tskaltubo karst massif, Zeda Kvilishori Cave , 4221’39.49”N, 4237’54.91”E, 249 m alt .

Type material. Holotype,male on slide:twilight zone, 23.vii.2017, leg.G.Nebieridze(code GEOZQV20170723- 01). Paratypes (same data as holotype): three males on slides, leg. G. Nebieridze (code GEOZQV20170723-02, 03 and 04). One specimen mounted on SEM stub, leg. G. Nebieridze (GEOZQV20170723-05) .

Repository. Holotype GEOZQV20170723-01 and paratype GEOZQV20170723-02 are deposited at FSCA and paratypes GEOZQV20170723-03, 04 and 05 are deposited at ISIZU.

Description. Body length up to 3.00 mm, excluding antennae and furcula.

Colour. Body grey, habitus as in Fig. 4 View FIGURE 4 .

Scale Distribution. Scales are present dorsally on Ant. I–II, head, body, all leg segments, both faces of collophore and ventral face of furcula. Postlabial region of head with few or no scales.

Head. Ratio body length to antennae length up to 1.05. Eye number difficult to ascertain under compound microscope, apparently varying from 1 to 5, cornea poorly differentiated, vestigial ( Fig. 7 View FIGURES 7–9 ). Head dorsally with 1 unpaired (A 0), and 6 paired Mc: 2 anterior (A 2, A 3), 2 interocular (S 1, S 4) and 2 postocular (Pa 3, Pa 5) distributed as in Fig. 7 View FIGURES 7–9 . Posterior margin of head with a row of evenly size mesochaetae. Prelabral and labral chaetae smooth ( Fig. 5 View FIGURES 5–6 ): prelabral chaetae 6 (3+3); labrum with 554 papillate chaetae as typical for genus; distal margin of labrum with 4 elongate, thin-walled, flexible papillae ( Fig. 5 View FIGURES 5–6 ). Sclerotized head of maxilla with 2 large and 2 or 3 small teeth; maxillary lamellas as in Plutomurus shurubumuensis Barjadze, Jordana & Soto-Adames in Barjadze et al. 2018 . Outer maxillary lobe trifurcate, basal chaetae shorter than apical process; sublobal plate with 4 chaeta-like processes, one chaeta-like process is distinctly reduced and shorter than others (arrow in Fig. 19 View FIGURES 19–20 ).

Body. Dorsal bothriotrichal formula 2,1/0,0,1,2,0 ( Figs 8–10 View FIGURES 7–9 View FIGURE 10 ). Dorsal Mc formula 5,1/3,3,4,2,3 ( Figs 8–10 View FIGURES 7–9 View FIGURE 10 ). Thorax macrochaetotaxy as in Fig. 8 View FIGURES 7–9 : Th. II with 3 anterior and 2 posterior Mc; Th. III with 1 posterior Mc. Abdominal macrochaetotaxy as in Figs 9 View FIGURES 7–9 and 10 View FIGURE 10 : Abd. I–II each with 3 posterior Mc; Abd. III with 2 anterior and 2 posterior Mc as typical for genus; Abd. IV with 9 or 10 differentiated elements along posterior margin (labelled as 1–9 in Fig. 9 View FIGURES 7–9 ), element 9 always a large Mc, element 6 developed into a small Mc, all other elements always have small mesochaeta-like sockets; Abd. V with 3 posterior Mc, 1 additional lateral Mc always present, but often hidden by slide mounting induced deformation of cuticle, and segment may appear as having only 3 Mc ( Fig. 10 View FIGURE 10 ).

Legs. Hind legs ( Fig. 11 View FIGURE 11–18 ) with well-developed trochanteral (30 chaetae) and femoral (24 chaetae) organs (holotype); posterior face of tibiotarsus with 1 outstanding inner, basal spine-like chaeta, (arrow in Fig. 17 View FIGURE 11–18 ) resulting in a 001 tibiotarsal spine formula. Tenent hair acuminated ( Fig. 16 View FIGURE 11–18 ). Ratio hind unguis: unguiculus: tenent hair as 1.95–2.73: 1.55–2.10: 1 (n=3). Inner edge of unguis on all legs with one characteristically minute proximal unpaired tooth (a in Fig. 16 View FIGURE 11–18 ), and 1–3 larger distal unpaired teeth (b–d in Fig. 16 View FIGURE 11–18 ). Unguis III with lateral teeth 0.25–0.61 as long as length of inner edge (n=4). Unguiculus lanceolate, tapered, with 2 internal lamellae bearing 0–4 teeth ( Figs 6 View FIGURES 5–6 and 16 View FIGURE 11–18 ).

Collophore. Anterior, posterior and lateral faces with 19, about 50 and 47 smooth chaetae respectively ( Fig. 14 View FIGURE 11–18 ).

Tenaculum. Corpus with one smooth chaeta; rami with 4 + 4 teeth ( Fig. 12 View FIGURE 11–18 ).

Furcula. Ratio manubrium: dens: mucro as 4.03–4.61: 7.84–9.56: 1 (n=3 including holotype). Outer margin of basal segment of dens with 2–4 apically acuminate macrochaetae, distal macrochaeta largest, proximal shortest. Inner edge of dens basally with well differentiated spine-like chaetae ( Fig. 18 View FIGURE 11–18 ); spines on basal segment of dens forming 2–3 short and poorly organized rows, upper row usually formed by 2 large, well-differentiated spines; spines on distal segment of dens forming a single row extending between 0.34–0.37 of length of distal segment of dens; spines on proximal portion of distal segment of dens always small, terminal spine always largest in row; long spines intercalated between short spines. Total dental spines number ( Fig. 18 View FIGURE 11–18 ) as 6–10 II–III / 9–13 III–VI (Arabic numbers represent small spines; Roman numerals in bold Italics represent large spines, on proximal/distal segments of dens). Dental spines have minute spinules on basal third ( Fig. 15 View FIGURE 11–18 ). Mucro with 2 basal and 2 distal teeth (202 formula) ( Fig. 13 View FIGURE 11–18 ).

Variation. The vestigial condition of most eyes makes it difficult to determine the number of corneas on slide mounted specimens. The number of teeth on the inner lamellae of the unguiculus varies from 0 to 4 and the number of teeth on the unguis varies between 2 to 4.

Discussion. The new species is the only member of Plutomurus with 3+3 prelabral chaetae, acuminate tenent hair, 001 tibiotarsal spine-like chaeta, an evidently reduced process on the sublobal plate of the outer maxillary lobe and five dorsal macrochaetae on Th II. Only two other species ( Plutomurus kelasuricus Martynova, 1969 , and P. eristoi Barjadze, Baquero, Soto-Adames, Giordano & Jordana, 2016 ) share with the new species the acuminate tenent hair, 3+3 prelabral chaetae and tibiotarsi with 001 outstanding spine-like chaeta. From P. kelasuricus the new species differs in having minute empodial teeth (large in P. kelasuricus ), and in having one chaeta-like process on the sublobal plate of the outer maxillary lobe much reduced (arrow in Fig. 19 View FIGURES 19–20 ) (normally developed in P. kelasuricus from type locality‒ ‒Kelasuri Cave (Tsebelda karst massif, Gulripshi Municipality, Abkhazia, Georgia) ( Fig. 20 View FIGURES 19–20 ). In addition to the fact that they occupy different, isolated cave massifs, the new species is found in the Sataplia-Tskaltubo karst massif, whereas P. kelasuricus inhabits the Tsebelda karst massif, located nearly 140 km away.

The new species differs from P. eristoi by the presence of five Mc on Th. II, while P. eristoi lacks Mc on Th. II; and by the presence of two posterior Mc on Abd. IV, whereas P. eristoi carries only 1 posterior Mc.

Etymology. The species is named after Prof. Rafael Jordana (University of Navarra, Spain), in recognition of his contributions disentangling the Gordian Knot of species level taxonomy in Plutomurus , and in gratitude for his work on the springtail fauna of Georgia.

Ecology. The body and eye patch pigmentation, together with the thick, toothed unguis suggest that this is a troglophilous species.