Penthalodes caucasicus, Khaustov & Kravchenko, 2023

Khaustov, Alexander A. & Kravchenko, Sergey V., 2023, First record of the genus Penthalodes (Acari: Eupodoidea: Penthalodidae) from Russia, with description of a new species, Persian Journal of Acarology 12 (2), pp. 161-172 : 162-167

publication ID	https://doi.org/ 10.22073/pja.v12i2.80042
publication LSID	lsid:zoobank.org:pub:A409FD21-52AA-488D-8170-746ECCF9A179
persistent identifier	https://treatment.plazi.org/id/03E9EC0C-FFF3-913E-FE5C-ACBBCEC1F7AC
treatment provided by	Felipe
scientific name	Penthalodes caucasicus
status	sp. nov.

Treatment

Penthalodes caucasicus sp. nov. ( Figs. 1–7 View Figure 1 View Figure 2 View Figure 3 View Figure 4 View Figure 5 View Figure 6 View Figure 7 )

http://zoobank.org/ urn:lsid:zoobank.org:act:A7F6E478-5D29-45F9-8404-AFD18E7E49B3

Description (female, n = 6)

Idiosoma – Ovate, egg-shaped ( Fig. 5F View Figure 5 ). Length of idiosoma including epirostrum 480 (445– 490), greatest width 350 (330–370). Dorsum of idiosoma with characteristic Y-shaped impression ( Fig. 4A View Figure 4 ). Dorsal integument with numerous pointed and hooked distally cuticular projections usually forming polygonal ornamentation ( Figs. 4B, C View Figure 4 ; 5A View Figure 5 ). Naso small, ovate, located far from anterior margin of idiosoma and densely covered by tiny cuticular projections ( Figs. 4B–D View Figure 4 ); in specimens mounted on slides naso usually hided under anterior part of prodorsum ( Fig. 1A View Figure 1 ). Eyes ovoid, covered with numerous cuticular projections and located posteromesad setae sc2 ( Fig. 4B View Figure 4 ). Epirostrum trilobed, with numerous cuticular projections as on dorsal idiosoma ( Fig. 4E View Figure 4 ); lateral lobes more than half as long as median one ( Fig. 1A View Figure 1 ), in some specimens poorly visible; median lobe subtriangular in shape, with rounded distal end. Setae v1 very small 5 (4–6), smooth and pointed, located on naso ( Fig. 4D View Figure 4 ); their bases widely separated; trichobothria sc1 59 (59) pilose in basal part and with long sparsely distributed projections in distal part ( Fig. 5A View Figure 5 ); setae v2, sc2, c1, c2, d1, e1, f1, f2, h1, and h2 subequal (25–30), of complex shape, pilose in basal half and with 3–4 long and pointed branches ( Figs. 4B, C View Figure 4 , 5B, C View Figure 5 ). Lyrifissures ia, im, ip, and ih long, slit-like; ia located posterolaterad setae c1, im posterolaterad setae d1, ip anterolaterad f1, and ih anterolaterad ps3. Ventral idiosoma with short, simple cuticular projections ( Figs. 5B, E, F View Figure 5 ). All ventral setae plumose. Genital valves with nine pairs of genital setae, one of which located laterally ( Fig. 5E View Figure 5 ); 10 pairs of aggenital setae and one pair of pseudanal setae. Primary genital opening with seven pairs of pilose eugenital setae and two pairs of large genital papillae ( Fig. 5E View Figure 5 ). Epimeral formula: 2(1b, 1с) –1(2b) –2(3b, 3c) –2(4b, 4c); three pairs of intercoxal setae (1a, 3a, 4a). Coxisternal fields I with characteristic tubercles.

Gnathosoma ( Figs. 2 View Figure 2 , 6A–C View Figure 6 ) – Chelicerae without setae; dorsal surface with numerous tiny cuticular projections, ventral surface smooth; fixed digit bifid distally; movable digit (dm) strongly sclerotized and characteristically bent ( Figs. 2A View Figure 2 , 6A View Figure 6 ). Subcapitulum with short, smooth adoral setae or 1 and or 2, located subterminally on membranous malae ( Figs. 6B, C View Figure 6 ); subcapitular setae sbc1 and sbc2 subequal, plumose. Palp ( Figs. 2B View Figure 2 , 6C View Figure 6 ) 155 (145–160) long; number of setae and solenidia on palp segments: 0–2–3–9(1); setae p’, p” and acm of palptarsus pilose in basal half and with spoon-like distal half ( Fig. 2B View Figure 2 ), other palpal setae plumose; solenidion ω 5 (4–5) on palptarsus located in depression ( Fig. 6C View Figure 6 ); palptarsus about twice longer than its width. Palptibia with spiniform ventrodistal process. Coxal supracoxal seta not evident.

Legs ( Figs. 3 View Figure 3 , 6C–F View Figure 6 , 7 View Figure 7 ) – Integument on leg segments with relatively big and tiny cuticular projections ( Figs. 6C–F View Figure 6 , 7A–F View Figure 7 ). Relative lengths of legs: I> IV> III> II. Lengths of legs: I 350 (345–355), II 270 (265–275), III 280 (275–285), IV 335 (330–340). Femora not divided. Leg I ( Figs. 3A, B View Figure 3 , 6C–F View Figure 6 , 7A, F View Figure 7 ): supracoxal seta el smooth, setiform, hardly visible dorsally posteriad trochanter; setal formula: Tr–1 (v’), Fe–9 (d, l’, l”, v’, v”, bv”, d1, v1’, l1’), Ge–5(1+1 k) (d, l’, l”, v’, v”, 1 σ, 1 k), Ti–6(2+1) (d, l’, l”, v’, v”, v1’, 2 φ, 1 k), Ta–23(3+1) (pd, ft’, ft”, tc’, tc”, it’, it”, p’, p”, u’, u”, pv’, pv”, pl’, pl”, v1’, v1”, v2’, v2”, v3’, v3”, v4’, v4”, 3 ω, 1 ε). Famulus ε 4 (3–4) smooth, short, blunt-tipped, located in depression anterolaterad setae ft” ( Figs. 6C, E View Figure 6 ); famulus k on tibia very small, spiniform, located in depression together with solenidion φ1 ( Fig. 7A View Figure 7 ); famulus k on genu very short, spiniform, located dorsally near distal margin of segment; solenidia φ2 9 (8–9) on tibia and σ 12 (11–12) on genu short, baculiform. Rhagidial organ I consist of three semierect solenidia arranged in longitudinal line in one shallow depression ( Figs. 6C, D View Figure 6 ); lengths of solenidia: ω1 9 (8–10), ω2 10 (8–10), ω3 10 (8–10). All setae of trochanter and femur, as well as setae l’ and (v) of genu pointed, plumose in basal half and smooth in distal half ( Fig. 7F View Figure 7 ); other leg setae plumose with short smooth blunt-ended tip ( Fig. 6C View Figure 6 ). Leg II ( Figs. 3C, D View Figure 3 , 7B–E View Figure 7 ): setal formula: Tr– 1 (v’), Fe–8(d, l’, l”, v’, bv”, d1, v1’, l1’), Ge–5(1+1) (d, l’, l”, v’, v”, 1 σ, 1 k), Ti–6(2) (d, l’, l”, v’, v”, v1’, 2 φ), Ta–16(3+1) (pd, ft’, tc’, tc”, it’, it”, p’, p”, u’, u”, pv’, pv”, v1’, v1”, v2’, v2”, 3 ω, 1 ε). Famulus ε 3 (3) smooth, short, blunt-tipped, semierect, located laterad solenidion ω1 ( Figs. 7B, C View Figure 7 ); famulus k on genu very short, spiniform, located dorsally near distal margin of segment; solenidion φ1 on tibia situated in depression ( Figs. 7D, E View Figure 7 ); solenidia φ2 9 (8–9) on tibia and σ 10 (9–10) on genu short, baculiform. Rhagidial organ II consist of three semierect solenidia arranged in longitudinal line in one shallow depression ( Figs. 7B, C View Figure 7 ); lengths of solenidia: ω1 10 (8–10), ω2 9 (8–19), ω3 9 (8–10). All setae of trochanter and femur, as well as setae l’ and (v) of genu pointed, plumose in basal half and smooth in distal half; other leg setae plumose with short smooth blunt-ended tip ( Fig. 6C View Figure 6 ). Leg III setal formula: Tr–1 (v’), Fe–6(d, l’, v’, ev’, d1, l1’), Ge–5(1) (d, l’, l”, v’, v”, 1 σ), Ti–6(1) (d, l’, l”, v’, v”, v1’, φ), Ta–15 (ft’, tc’, tc”, it’, it”, p’, p”, u’, u”, pv’, pv”, v1’, v1”, v2’, v2”). Solenidia φ 8 (7–9) on tibia and σ 9 (8–9) on genu short, baculiform. All setae of trochanter and femur, as well as setae l’ and (v) of genu pointed, plumose in basal half and smooth in distal half; other leg setae plumose with short smooth blunt-ended tip. Leg IV ( Figs. 3G, H View Figure 3 ): setal formula: Tr–1 (v’), Fe–4(d, v’, ev’, d1), Ge–4(1) (d, l’, v’, v”, 1 σ), Ti–6(1) (d, l’, l”, v’, v”, v1’, φ), Ta–15 (ft’, tc’, tc”, it’, it”, p’, p”, u’, u”, pv’, pv”, v1’, v1”, v2’, v2”). Solenidia φ 9 (8–9) on tibia and σ 10 (8–10) on genu short, baculiform. All setae of trochanter and femur, as well as most setae of genu (except d) pointed, plumose in basal half and smooth in distal half; setae (it), (p) and (u) widened distally, plumose; other leg setae plumose.

Male and immatures unknown.

Type material

Female holotype, slide ZISP T-Eup-1, Russia, Krasnodar Krai, vicinity of Sochi, Khosta District, moss near the Agura River , 43° 32' 38" N, 39° 48' 26" E, 3 December 2022, coll. S. V. Kravchenko GoogleMaps ; paratypes: 16 females, same data GoogleMaps .

Type deposition

The holotype and four female paratypes are deposited in the acarological collection of the Zoological Institute of RAS, Saint Petersburg, Russia ; other paratypes are deposited in the collection of the Tyumen State University Museum of Zoology , Tyumen, Russia .

Differential diagnosis

The new species is most similar to P. polonicus in having all dorsal setae of similar complex shape with 3–4 long and pointed branches. In other described species at least setae f1, f2 and h1 pilose, without long branches. The new species differs from P. polonicus in having three solenidia in rhagidial organ I (vs. two in P. polonicus ); bases of setae v1 widely separated (vs. bases of setae v1 almost contiguous in P. polonicus ); and femoral formula 9–8–6–4 (vs. 9–7– 5–7 in P. polonicus ). The new species is also similar to P. ovalis sensu Kaluz, 2000 in having same chaetotaxy of legs (except tarsi) and similar shape of setae v2, sc2 and c2. The new species differs from P. ovalis by the shape of opisthosomal setae being multibranched (vs. plumose with fine distal filament in P. ovalis as illustrated in Fig. 10(d) in Baker (1990)); in having three solenidia in rhagidial organ I (vs. two in P. ovalis ); and tarsal formula 23–16–15–15 (vs. 20–14–14– 14 in P. ovalis ).

Etymology

The name of the new species refers to its geographical distribution in Caucasus.