Eutrombicula picunche, Stekolnikov, Alexandr A. & González-Acuña, Daniel, 2015

Stekolnikov, Alexandr A. & González-Acuña, Daniel, 2015, A review of Chilean chiggers (Acari: Trombiculidae), with the description of a new genus and ten new species, Zootaxa 3964 (1), pp. 1-43 : 9-11

Eutrombicula picunche sp. nov.

(Figs. 5, 6)

Diagnosis. SIF = 7BS-N-2-3111.1000; fsp = 7.7.7; fCx = 1.1.1; fSt = 2.2; fPp = B/B/NNB; fSc: PL> AM = AL; Ip = 720; fD = 2H-6-6-4-2; fV = 6-2-2-2; DS = 20; VS = 12; NDV = 32. Standard measurements of holotype: AW 61, PW 72, SB 31, ASB 32, PSB 22, SD 53, P-PL 17, AP 23, AM 23, AL 23, PL 35, S 54, H 38, D min 24, D max 34, V min 29, V max 36, pa 248, pm 225, pp 247, TaIIIL 65, TaIIIW 13, m-t 0.333.

Description (larva). IDIOSOMA. Eyes 2 + 2, on ocular plate. One pair of humeral setae, 18 thin, moderately barbed dorsal idiosomal setae, fD = 2H-6-6-4-2; 4 sternal setae; 12 ventral setae; total number of idiosomal setae excluding coxal and sternal 32.

FIGURE 5. Eutrombicula picunche sp. nov. (holotype). A, scutum and eyes; B, dorsal idiosomal seta of 1st row; C, preanal ventral idiosomal seta; D, arrangement of ventral idiosomal setae; E, arrangement of dorsal idiosomal setae. Scale bars: 50 Μm (A), 20 Μm (B, C), 100 Μm (D, E).

GNATHOSOMA. Cheliceral blade with tricuspid cap; cheliceral base with dense puncta in proximal part; gnathobase with transverse striations and sparse puncta; palpal femur with few puncta; gnathobase with 1 pair of branched setae; galeala nude; palpal claw with 2 subequal prongs separated from each other by shallow cleft; seta on palpal femur branched; seta on palpal genu branched; dorsal and lateral palpal tibial setae nude, ventral palpal tibial seta branched; palpal tarsus with 7 branched setae, nude subterminala, and tarsala.

SCUTUM. Nearly pentagonal, with broadly rounded posterior margin, covered by sparse puncta of varying size; AM base posterior to level of ALs; SB anterior to level of PLs (PSB—P-PL = 5); PL> AM = AL; flagelliform sensilla with 8 rather long branches in distal half.

LEGS. All 7-segmented, with 1 pair of claws and claw-like empodium. Leg I: coxa with 1 non-specialized branched seta (1B); trochanter 1B; basifemur 1B; telofemur 5B; genu 4B, 3 genualae, microgenuala; tibia 8B, 2 tibialae, microtibiala; tarsus 22B, tarsala 12 long, microtarsala distal to tarsala, subterminala, parasubterminala, pretarsala. Leg II: coxa 1B; trochanter 1B; basifemur 2B; telofemur 4B; genu 3B, genuala; tibia 6B, 2 tibialae; tarsus 16B, tarsala thin, 13 long, microtarsala proximal to tarsala, pretarsala. Leg III: coxa 1B; trochanter 1B; basifemur 2B; telofemur 3B; genu 3B, genuala; tibia 6B, tibiala; tarsus 14B, mastitarsala with 3 cilia.

Host. Liolaemus fuscus Boulenger ( Squamata : Liolaemidae ).

Type material. Holotype larva ( ZIN collection No. 8506, T-Tr.-68) ex Liolaemus fuscus No. 52, CHILE: Valparaíso Region, Quillota Province, La Campana National Park, 5 March 2013, coll. D. González-Acuña.

Etymology. The species is named after Picunche people, an ethnic group which inhabited the territory where the type locality is situated prior to extinction during the colonial period.

Remarks. The new species is very close to Eutrombicula paula Stekolnikov and González-Acuña, 2010 and differs from it in the presence of 3 genuala on leg I vs. 2 genualae I, prongs of palpal claw separated by shallow (vs. deep) cleft, a somewhat longer scutum (ASB = 32 vs. 22, SD = 53 vs. 41), and in longer posterior scutal and idiosomal setae (PL = 35, H = 38, D min = 24, D max = 34, V min = 29, and V max = 36 vs. 26, 27, 17, 25, 23, and 29, respectively).