Charimachilis petrophilus Kaplin, 2022

Kaplin, V. G. & Martynov, V. V., 2022, A new species of the bristletail genus Charimachilis Wygodzinsky, 1939 (Microcorypha: Machilidae) from Eastern Ukraine, Far Eastern Entomologist 449, pp. 1-8 : 3-8

Charimachilis petrophilus Kaplin , sp. n.

http://zoobank.org/NomenclaturalActs/ 102AEA04-F2FC-441A-A0CA-23557FE47991

Figs 1–14

TYPE MATERIAL. Holotype – ♀, Ukraine: Donetsk region, near Dmitrievka ,

47°56ʹ03ʹʹ N, 38°56ʹ15ʹʹ E, 50 m, petrophytic steppe, under stones, 23.III 2020, leg.

V. Martynov ( VIZR) (in slides). Paratypes: 5♀, same locality, data and collector as for holotype ( VIZR) (2♀ in slides; 3♀ in 75% ethanol) .

DESCRIPTION. Female. Body length 7.6–9.2 mm; body width 2.2–2.3 mm;

antennal length 5.0– 5.6 mm; cercal length 2.9–3.3 mm; total eyes width 0.89–0.94

mm, eye length 0.43–0.46 mm; paired ocelli width 0.39–0.41 mm, length 0.14–0.16

mm. Coxal styli length 0.51–0.54 mm. Ovipositor length 1.4–1.5 mm.

General body color whitish, with purple-brown hypodermal pigment of faint or medium intensity only on antennal base, frons, gena, labrum, mandible, stipes and galea of maxilla, first article of maxillary palpus, coxa. Color of scales on upper and lower surface of the body brown. Antennae shorter than body. Distal chains of flagellum divided into 6–12 annuli ( Fig. 1 ). Cercus 0.32–0.39 times as long as body length. Apex of cercus with one large and one lateral easily broken spike ( Fig. 2 ).

Divisions of cerci, except for apical three, with 1–3 colorless supporting macrochaetae on inner side.

Compound eyes black. Ratio of length to width of compound eye about 0.90–

0.94; ratio of contact line length to eye length 0.42–0.47. Paired ocelli shoe-shaped,

dark brown with white rim, located in front of eyes. Distance between inner margins of ocelli about 0.14–0.15 and between their outer margins 0.80–0.86 total width of compound eyes ( Fig. 3 ).

Apical article of maxillary palpus 0.96–1.04 times as long as preceding one.

Dorsal surface of 7th, 6th, and 5th articles of maxillary palpus with 13, 11, and 5

hyaline spines, respectively ( Fig. 4 ). Apical article of labial palpus triangularly oval,

2.5–2.7 times as long as wide ( Fig. 5 ). Mandibles with four distal teeth ( Fig. 6 ).

Fore and middle femur and tibia widened. Ratios of lengths to widths of femur,

tibia and tarsus as shown in Table 1. Ratio of length of 3rd tarsomere to total length of tarsus 0.32–0.34. Pretarsus with well developed claws and with two support pro-

trusions ( Fig. 7 ). Ventral surface of femora, tibiae and tarsi with spine-like chaetae as shown in Table 2. Middle and hind legs with coxal styli ( Fig. 8 ). Ratio of styli length to width of middle and hind coxae about 1.6–1.8.

Abdominal segments I–VII with 1 + 1 eversible vesicles. Posterior angle of urosternites sharp, about 60–80°. Ratios of lengths of urosternite and urocoxite II–

VI 0.65–0.70; urostylus (without apical spine) and urocoxite II–VII 0.46–0.55, VIII

– 0.86, IX – 0.50; apical spine and urostylus (without apical spine) II–VIII 0.44–

0.46, IX – 0.31 ( Figs 9–13 ). Inner posterior lobes of urocoxites VII protruding;

ratio of length to width of one lobe about 0.66 ( Fig. 10 ).

Urocoxites IX with 1–2 + 1–2 outer and 5–7 + 5–7 inner sublateral, VIII with 2–

3 + 2–3, VII with 1–2 + 1–2 sublateral spines ( Figs 9, 11, 12 ). Urocoxites I–VI without sublateral spines.

(1, 3). 1 – chain of distal part of flagellum; 2 – apex of cercus; 3 – compound eyes and paired ocelli (front view); 4 – maxillary palpus; 5 – labium (part) and labial palpus; 6 – distal part of mandible; 7 – pretarsus; 8 – hind leg. Scale bars = 0.1 mm.

urocoxites VII (part); 10 – stylus of urocoxite VII; 11 – coxite VIII with anterior gonapophysis; 12 – coxite IX; 13 – stylus of urocoxite IX; 14 – posterior gonapophysis. Scale bars = 0.1 mm.

Ovipositor weakly sclerotized, thickened, completely concealed by urocoxites

IX, typical of genus Charimachilis . Anterior and posterior gonapophyses with respectively 16 and 17 divisions ( Figs 11, 14 ). Ultimate division of anterior gonapophysis with preapical spine and 2 small apical lateral projections, one of which is pointed and sclerotized. Apical spines as long as 2 apical divisions combined.

Anterior gonapophysis with 4 or 5 lateral digging spikes. Posterior gonapophyses with well developed, sclerotized curved apical horn and preapical spine, as long as 3

or 4 apical divisions combined. Distribution of sensory and simple chaetae on divisions of anterior and posterior gonapophyses as in Figs 11 and 14 .

Male. Unknown.

Pair of legs

Segments

fore middle hind

1st 4 6 8–10

Tarsomeres 2nd 8 7–8 9–11

3rd 0 0 0

Tibia 2–3 5–6 10–12 Femur 0–1 1 2–4

DIFFERENTIAL DIAGNOSIS. Charimachilis petrophilus sp. n. most closely resembles C. taurica and C. rostoviensis in ratio of lengths of apical article of maxillary palpus and the preceding one; posterior angle of urosternites II–V; ratio of lengths of stylus (without apical spine) and urocoxite II–VII; number of inner sublateral spines on urocoxite IX; divisions and lateral digging spikes on anterior gonapophyses ( Table 3). New species differs from C. taurica and C. rostoviensis by the ratio of contact line length to eye length; number of hyaline spines on dorsal surface of 5th, 6th and 7th articles of maxillary palpus; ratio of lengths of stylus

(without apical spine) and urocoxites VIII and IX; number of divisions in posterior gonapophysis. C. petrophilus sp. n. differs from C. ukrainensis and C. wahrmani by the ratios of contact line to eye length, distance between inner margins of ocelli to total width of compound eyes, lengths of stylus (without apical spine) and urocoxite

IX; and from C. wahrmani in the number of divisions in gonapophyses VIII and IX

( Table 3). The new species is probably parthenogenetic, similar to most its congeners.

ETYMOLOGY. The new species is named after the predominant habitat type.

Kaplin, V.G. 2019. A review of the distribution and phylogenetic relationships of bristletails of the genus Charimachilis Wygodz. (Archaeognatha, Machilidae) with descriptions of larvae of Ch. caucasica Kapl. and of a new species from Belgorod Province. Entmological

Review, 99(1): 91–115. DOI: 10.1134/S0013873819010135

Kaplin, V.G. 2021. A new species of bristletails of the genus Charimachilis (Microcoryphia:

Machilidae ) from Crimea. Russian Entomological Journal, 30(2): 123–128.

Kaplin, V.G. & Martynov, V.V. 2020. Three new species of bristletails of the families Meiner-

tellidae and Machilidae (Archaeognatha) from Ukraine and Southern Russia. Acta Ento-

mologica Musei Nationalis Pragae, 60(2): 463–474. DOI: 10.37520/aemnp.2020.30.

Figures

Figs 1–8. Charimachilis petrophilus Kaplin, sp. n., holotype ♀ (2, 4–8) and paratype ♀

Figs 9–14. Charimachilis petrophilus Kaplin, sp. n., holotype ♀. 9 – urosternite and