New species and new records of chigger mites (Acariformes, Trombiculidae) from Cambodia Author Antonovskaia, Anastasia A. 0000-0001-8638-7151 Zoological Institute of the Russian Academy of Sciences, Universitetskaya embankment 1, Saint Petersburg 199034, Russia; Author Morand, Serge 0000-0003-3986-7659 Author Stekolnikov, Alexandr A. Zoological Institute of the Russian Academy of Sciences, Universitetskaya embankment 1, Saint Petersburg 199034, Russia; text Zootaxa 2024 2024-02-05 5406 2 343 358 http://dx.doi.org/10.11646/zootaxa.5406.2.7 journal article 10.11646/zootaxa.5406.2.7 1175-5326 10618283 F65BF05F-CE34-466C-97F7-7AA29806FDF7 Leptotrombidium mondulkiri sp. nov. ( Figs. 1A, B , 2 , 3 ) Diagnosis. SIF = 7B-B-3-2111.0000; fPp = N/N/BNB; fSc: AM> PL ≥ AL; SB-PL; fCx = 1.1.1; fSt = 2.2; Ip = 686–764; fD = (5–7)H-(16–21)-(12–16)-(9–18)-(2–10)-(2–9)-(2–7)-(1–5)-(0–3)-2(0); DS = 63–83; V = 48–71; NDV = 120–147. Standard measurements are in Table 1 . TABLE 1. Standard measurements of Leptotrombidium mondulkiri sp. nov. (for AL n = 9, for S n = 2, for other variables n = 10).

Range	Mean	Holotype
AW	64–70	67	64
PW	78–85	82	79
SB	32–36	34	32
ASB	25–31	27	26
PSB	11–13	12	12
SD	37–42	39	38
AP	23–29	26	27
P-PL	9–14	11	12
AM	46–58	51	46
AL	34–42	40	42
PL	39–45	42	41
S	66–67	67	67
H	35–45	40	37–41
D min	31–35	32	31
D max	37–41	40	37
V min	18–24	21	22
V max	32–38	34	32
pa	236–267	247	236
pm	204–232	212	205
pp	237–265	249	246
Ip	686–764	708	687
TaIIIL	58–65	62	62
TaIIIW	12–14	13	12
DS	63–83	72	74
V	48–71	60	57
NDV	120–147	132	131

Description (larva). IDIOSOMA ( Figs. 1A, B , 2B–G ). Eyes 2+2, on ocular plate; 63–83 heavily barbed dorsal idiosomal setae, including 5–7 humeral setae; separation of humeral and post-humeral setae sometimes unclear; 16–21 setae in 1 st post-humeral row (C excluding humeral setae), 12–16 setae in 2 nd row (D), 9–18 setae in 3 rd row (E); 4 sternal setae and 48–71 ventral setae; total number of idiosomal setae excluding coxal and sternal 120–147. FIGURE 1. Leptotrombidium mondulkiri sp. nov. , holotype. A —anterior part of idiosoma, dorsal aspect; B —sternal area, ventral aspect. Leptotrombidium pilosum cambodiensis subsp. nov. , paratype ZIN 14251. C —anterior part of idiosoma, dorsal aspect; D —sternal area. Scale bars: 100 µm. GNATHOSOMA ( Figs. 3A, B ). Cheliceral blade with tricuspid cap; gnathobase and palpal femur moderately covered with puncta; gnathobase with one pair of branched gnathocoxal (tritorostral) setae; galeal (deutorostral) seta heavily branched; palpal claw with three prongs; dorsal and ventral palpal tibial setae branched, other palpal setae nude; palpal tarsus with seven branched setae and basal tarsala ( ω ). SCUTUM ( Figs. 1A , 2A ). Rectangular, moderately covered with puncta, with posterior margin straight or slightly concave in center; areas near bases of setae lack of puncta; AM base posterior to level of ALs; SB nearly at level of PLs (P-PL – PSB = –3–3, mean 0); AM> PL ≥ AL; scutal setae barbed similarly to dorsal idiosomal setae; flagelliform sensilla (trichobothria) with 8–10 branches in distal half. LEGS ( Figs. 3C–E ). All 7-segmented, with a 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, 2 genualae ( σ ), microgenuala ( κ ); tibia 8B, 2 tibialae ( φ ), microtibiala ( κ ); tarsus 22B, tarsala ( ω ) (18 long), microtarsala (famulus, ε ) distal of tarsala, subterminala ( ζ ), parasubterminala ( z ), pretarsala ( ζ ). Leg II: coxa 1B; trochanter 1B; basifemur 2B; telofemur 4B; genu 3B, genuala ( σ ); tibia 6B, 2 tibialae ( φ ); tarsus 16B, tarsala ( ω ) (14 long), microtarsala (famulus, ε ) behind tarsala, pretarsala ( ζ ). Leg III: coxa 1B; trochanter 1B; basifemur 2B; telofemur 3B; genu 3B, genuala ( σ ); tibia 6B, tibiala ( φ ); tarsus 15B. Type material. Larval holotype ( ZIN 14237 , L-521) ex B. savilei No. C 0683, CAMBODIA , Mondulkiri Province , Keo Seima , 23 November 2009 ; nine larval paratypes ( ZIN 14196 , 14206 , 14215 , 14224 , 14242 , 14246– 14248 , 14250 ) with same data . FIGURE 2. Leptotrombidium mondulkiri sp. nov. , holotype (A–E), paratype ZIN 14250 (F, G). A —scutum; B —humeral seta; C —dorsal idiosomal seta; D —postanal seta; E —preanal seta; F —arrangement of ventral idiosomal setae; G —arrangement of dorsal idiosomal setae. Abbreviations: AM—anteromedian seta; AL—anterolateral seta; H—humeral setae; PL—posterolateral seta; S—sensillum (trichobothrium). Scale bars: 50 µm (A–E), 100 µm (F, G). Etymology. The species name derived from the name of province, where the type locality is situated. Differential diagnosis. The new species is similar to Leptotrombidium macacum (Womersley, 1952) , belonging to the binbium species group ( Vercammen-Grandjean & Langston 1976 ; Stekolnikov 2013 ), and differs from the latter in having 5–7 humeral setae vs. 2 (in L. macacum ), more numerous idiosomal setae (NDV = 120–147 vs. 94; 16–21 setae in 1 st post-humeral row vs. 10; 12–16 setae in 2 nd row vs. 10), relatively wider scutum (AW 64–70 vs. 60–64, PW 78–85 vs. 72–76, and SB 32–36 vs. 30–31), and slightly shorter setae (H 35–45 vs. 45–47, D min 31–35 vs. 33–43, D max 37–41 vs. 42–58, V min 18–24 vs. 22–31, and V max 32–38 vs. 38–49).