Eutrombicula nerudai, 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 : 3-6

Eutrombicula nerudai sp. nov.

(Figs. 1, 2)

Diagnosis. SIF = 7 BS-N- 2 -3111.1000; fsp = 7.7.7; fCx = 1.1.1; fSt = 2.2; fPp = B/N/NNB; fSc: PL> AM> AL; Ip = 972–1091; fD = 2 H-[(10–11)-(4–5)]-(10–13)-(9–11)-…; DS = 43–52; VS = 31–38; NDV = 77–85. Standard measurements of holotype: AW 81, PW 92, SB 38, ASB 29, PSB 27, SD 56, P-PL 22, AP 27, AM 41, AL 36, PL 47, S 67, H 49, D min 33, D max 44, V min 34, V max 41, pa 342, pm 302, pp 342, Ip 986, DS 50, VS 31, NDV 81, TaIIIL 97, TaIIIW 15, m-t 0.352. Standard measurements of type series given in Table 1.

Note: The exact two-sided p-values of the Wilcoxon Mann-Whitney rank sum test for the difference between two samples are given. Values lesser than 0.05 are indicated by *.

Description (larva). IDIOSOMA. Eyes 2 + 2, on ocular plate, anterior larger. One pair of humeral setae, 41– 50 moderately barbed dorsal idiosomal setae, 1 st row of dorsal setae double, in holotype fD = 2 H-[10 - 4]- 12 - 10 - 4-5 - 3; 4 sternal setae; 31–38 ventral setae; total number of idiosomal setae excluding coxal and sternal 77–85.

GNATHOSOMA. Cheliceral blade with tricuspid cap; cheliceral base with dense puncta in proximal part; gnathobase with transverse striations, few large and many small puncta; palpal femur with few puncta; gnathobase with 1 pair of branched setae; galeala nude; palpal claw with 2 short subequal prongs separated from each other by shallow cleft; seta on palpal femur branched; seta on palpal genu nude; 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, dense puncta of moderate size on whole surface and very small inconspicuous puncta in anterior and central part; AM base at level of ALs; SB anterior to level of PLs (PSB—P-PL = 4–8; mean value 5.4); PL> AM> AL; flagelliform sensilla with about 5–6 branches of moderate length 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 (1 B); trochanter 1 B; basifemur 1 B; telofemur 5 B; genu 4 B, 3 genualae, microgenuala; tibia 8 B, 2 tibialae, microtibiala; tarsus 22 B, tarsala 16–17 long, microtarsala distal to tarsala, subterminala, parasubterminala, pretarsala. Leg II: coxa 1 B; trochanter 1 B; basifemur 2 B; telofemur 4 B; genu 3 B, genuala; tibia 6 B, 2 tibialae; tarsus 16 B, tarsala thin, 17 long, microtarsala proximal to tarsala, pretarsala. Leg III: coxa 1 B; trochanter 1 B; basifemur 2 B; telofemur 3 B; genu 3 B, genuala; tibia 6 B, tibiala; tarsus 14 B, nude mastitarsala.

Hosts. Liolaemus nitidus (Wiegmann) and L. platei Werner ( Squamata : Liolaemidae ).

Type material. Holotype larva ( ZIN collection No. 8492, T-Tr.- 66) ex Liolaemus nitidus No. IV 466 (28), CHILE: Atacama Region, Llanos de Challe National Park, 21 March 2011, coll. D. González-Acuña & S. Muñoz- Leal; 8 larvae paratypes (8491, 8493– 8499) with same data; 6 larvae paratypes (8500–8505) ex Liolaemus platei No. IV 175 (29), 23 March 2011, other data same.

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

Etymology. The species named after the great Chilean poet Pablo Neruda, the Nobel laureate of 1971 for Literature.

Remarks. The new species is similar to Eutrombicula macropus ( Womersley, 1936) and E. rioi ( Gunther, 1939) in the large number of idiosomal setae and fPp=B/N/NNB, but differs in the shape of palpal claw with subequal prongs separated by a shallow cleft (vs. prongs clearly different by size and separated by a deep cleft) and in the shape of scutum with SB closer to the level of PLs and the posterior margin less prominent.

Tables

TABLE 1. Standard measurements of Eutrombicula nerudai sp. nov. and E. mistrali sp. nov.

Variable	Eutrombicula nerudai		Eutrombicula mistrali		p-value
	Range Mean	Sample size	Range Mean	Sample size
AW	77–87 81	9	81–90 85	6	0.068
PW	90–97 94	9	92–103 97	6	0.13
SB	32–40 37	9	36–41 39	6	0.041*
ASB	27–32 29	9	25–31 27	6	0.12
PSB	27–29 28	9	23–26 25	6	0.00020*
SD	54–60 56	9	51–54 53	6	0.00080*
P-PL	20–25 22	9	18–22 20	6	0.024*
AP	23–30 26	9	24–27 26	6	1.00
AM	36–45 41	7	34–36 35	6	0.0023*
AL	34–41 38	9	30–34 32	6	0.00080*
PL	46–56 49	9	45–48 47	6	0.030*
S	61–67 65	4	64–68 66	2	0.67
H	47–53 51	9	45–50 48	6	0.050*
D min	28–36 32	8	25–31 28	6	0.014*
D max	42–52 46	8	41–45 43	6	0.037*
V min	28–37 33	8	23–29 27	6	0.0037*
V max	40–50 45	8	38–45 42	6	0.12
pa	337–374 351	9	337–360 342	6	0.37
pm	301–338 313	9	292–319 302	6	0.091
pp	335–378 354	9	333–349 338	6	0.020*
Ip	972–1091 1017	9	961–1028 982	6	0.062
DS	43–52 48	9	65–86 75	6	0.00040*
VS	31–38 33	9	45–50 47	6	0.00040*
NDV	77–85 81	9	112–131 122	6	0.00020*
TaIIIL	97–105 100	9	86–93 91	6	0.00040*
TaIIIW	15–16 15	9	15–19 16	6	0.78
m-t	0.333–0.368 0.347	9	0.330–0.394 0.360	6	0.28