Rogeracarus extraordinarius Stekolnikov, 2025

Rogeracarus extraordinarius Stekolnikov , sp. nov.

( Figs. 17A–C View FIGURE 17 , 18 View FIGURE 18 )

Diagnosis. SIF = 4B-N-3-1000.3100; fPp = B/B/NNB; fCx = 1.1.1; fSt = 2.2; fsp = 7.7.7; fD = 2H-6-6-6-6-2+(2–5), DS = 29–33, V = 21–49, NDV = 50–81; Ip = 443–504; eyes 1 + 1; scutum nearly trapezoidal, with small sparse puncta, its anteroir and posterior margins concave; ALs inserted on projected scutal corners; AM posterior to level of ALs; PLs extrascutal; sensillary bases at equal distances from ALs and PLs and much closer to lateral scutal margins than to each other; AM = PL> AL; sensilla clavate, densely covered with setules; microtarsala I ( ε) distal to tarsala I ( ω); microtarsala II ( ε) at level of tarsala II ( ω). Measurements are given in Table 7.

Description of larva. IDIOSOMA ( Figs. 17A–C View FIGURE 17 , 18A–F View FIGURE 18 ). Eyes 1 + 1; 29–33 short, densely barbed dorsal idiosomal setae, distribution by rows 2H-6-6-6-6-2+(2–5); two sternal setae between coxae I and II and two between coxae III; 21–49 ventral setae; NDV = 50–81.

GNATHOSOMA ( Fig. 18G–I View FIGURE 18 ). Cheliceral blade with tricuspid cap and one dorsal tooth; gnathobase (infracapitulum) with sparse small puncta, bears one pair of branched tritorostral setae; galeal (deutorostral) seta nude; palpal claw (odontus) with three prongs; palpal femoral and genual setae branched; dorsal and lateral palpal tibial setae nude, ventral seta branched; palpal tarsus with four unspecialized setae, branched or apparently nude, and tarsala ( ω).

SCUTUM ( Figs. 17C View FIGURE 17 , 18A View FIGURE 18 ). Nearly trapezoidal, with small sparse puncta, its anteroir and posterior margins concave; ALs inserted on projected scutal corners; AM posterior to level of ALs; PLs extrascutal; sensillary bases at equal distances from ALs and PLs and much closer to lateral scutal margins than to each other, surrounded by crests and cuticular striations; AM = PL> AL; sensilla clavate, densely covered with setules; all scutal setae barbed similarly to dorsal idiosomal setae.

LEGS ( Fig. 18J–L View FIGURE 18 ). All seven-segmented (with divided femur), with one pair of claws and claw-like empodium. Sensory setae: Leg I: 1 genuala ( σ), long setiform microgenuala ( κ), 2 rod-like tibialae ( φ) and setiform microtibiala ( κ) longer than tibialae, in distal part of segment, tarsala ( ω), famulus ( ε) distal to tarsala, subterminala ( ζ), nude parasubterminala ( z), pretarsala ( ζ). Leg II: 1 tibiala ( φ) in proximal part of segment, very thin tarsala ( ω), long setiform famulus ( ε) at level of tarsala, pretarsala ( ζ). Leg III: sensory setae absent. Unspecialized setae (leg I, II, III): coxa 1, 1, 1; trochanter 1, 1, 1; basifemur 1, 2, 2; telofemur 5, 4, 3; genu 4, 3, 3; tibia 8, 6, 6 (including one nude mastitibiala); tarsus 22, 14–15, 13 (including three nude mastitarsalae).

Type material. Holotype: larva ( ZIN 18436 View Materials ), ex Micaelamys namaquensis ( No. MfMn 24), South Africa, Western Cape, Matjesfontein Farm, near Ceres, Succulent Karoo , 24 October 2023, coll. Alyssa Little. Paratypes: eight larvae ( ZIN 18418–18423 View Materials , 18426 View Materials , 18429 View Materials ) ex M. namaquensis (Nos MfMn3, 6, 7, and 13), same locality, date, and collector ; four larvae ( ZIN 18348–18351 View Materials ) ex Otomys unisulcatus (Nos. ObOu05 and ObOu 12), South Africa, Western Cape, Ouberg Private Nature Reserve, near Montagu , Succulent Karoo , 7 and 9 November 2023, coll. Jessica Kipling ; one larva ( ZIN 18394 View Materials ) ex M. namaquensis ( No. ObMn 15), same locality, 6 November 2023, coll. Alyssa Little.

Etymology. The specific epithet extraordinarius (extraordinary) refers to the chaetotactic traits in this species, which are unique in chigger mites, such as the presence of only one tibiala II and microtibiala I longer than tibialae.