There are approximately 280 larval species in this important and worldwide genus, in two subgenera Leptus and Amaroptus (with only one species: L. (Amaroptus) vuki Haitlinger, 2000 (Southcott 1992; Haitlinger 2000; Beron 2008; Mąkol & Wohltmann 2012, 2013). Leptus larvae are ectoparasites of different arthropods specially insect orders e.g. Orthoptera, Coleoptera, and Lepidoptera (Welbourn, 1983) but their potential in biological control has not been investigated.

Mites of the genus Leptus are poorly studied in Iran. So far only six species have been described from Iran as follows: L. (L.) fathipeuri Haitlinger & Saboori, 1996; L. (L.) zhangi Saboori & Atamehr, 1999; L. (L.) esmailii Saboori & Ostovan, 2000; L. (L.) kamalii Karimi Iravanlou & Saboori, 2001; Leptus (Leptus) eslamizadehi Saboori, 2002; and L. (L.) delijanensis Khademi, Saboori & Hakimitabar, 2015 (Mąkol & Wohltmann, 2012; Khademi et al., 2015). In this paper, we describe the larva of L. (L.) tridentatus Saboori, Hakimitabar & Khademi sp. nov. from Damavand mountain, Tehran Province, Iran. Also, the first and second authors re-examained some species in private Haitlinger's collection and amend some of their meristic data or give new meristic data.

Larvae of L. (L.) tridentatus Saboori, Hakimitabar & Khademi n. sp. were collected from Damavand mountain, Tehran province, Iran, on 3 July 2009, by Masoud Hakimitabar. Specimens were collected from under a stone (off host) by minute brush. They were preserved in 70% ethanol, cleared in Nesbitt's fluid and mounted using Faure medium on microscope slides (Walter & Krantz, 2009). Figures were drawn and measurements were made using a BX51 Olympus microscope equipped with a drawing tube. The terminology and abbreviations used in the description are adapted from Haitlinger (2013) and Wohltmann et al. (2007). All measurements are given in micrometers (μm).

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Diagnosis — With three denticles on dorsal part of palpal tibial claw; palpal femur with one and palpal genu with two setae; fn Fe = 3-3-2; $im$30–44 setae between coxae II & III; Ti III < 225.

Description — Larva (N = 4) — Idiosoma oval in shape, and with $im$170–204 barbed setae. Scutum longer than or equal with wide, punctate, with two pairs of sensilla and two pairs of scutalae, anterior border deeply concave (Fig. 1), ASens and PSens barbed on distal 1/3; cuticular lines around bases of PSens, and parallel conjunct to posterolateral borders, also narrow cuticular lines beyond bases of ASens (Fig. 1A); AL longer than PL. One eye on each side of scutum, both circular in shape and 24–30 across.

Ventral surface of idiosoma with barbed sternalae; 2 barbed sternalae between coxae I, 6–7 barbed sternalae between coxae II; $im$30–44 barbed intercoxalae between coxae II and III and $im$46–56 barbed setae behind coxae III. Sternalae 1a longer than other sternalae (Fig. 1B). Coxae I-III each with one seta, coxa I with a peg-like supracoxal seta; coxalae 1b about twice the length of coxalae 2b; coxalae 3b longer than coxalae 2b; all coxalae barbed (Fig. 2). NDV = $im$272–287.

Gnathosoma narrow and cone-shaped, 173–210 long with barbed and thick galealae (Ga) and two pairs of hypostomalae, anterior hypostomalae (aHy) smooth, small and peg-like, posterior hypostomalae (pHy) thicker, stronger and barbed. Palpal femur with one and palpal genu with two barbed setae. Palpal tibia with three barbed setae, palpal tibial claw with 3 small denticles on dorsal side (Fig. 1C). Palpal tarsus with 8 setae including 4 barbed and 2 nude setae, a solenidion, and an eupathidium. Palpal setal formula: fPp= 0-B-BB-BBB-4B2Nωζ (Fig. 3). Supracoxal seta of palp (eP) peg-like, 5 long. Chelicerae, subcapitulum and palps with punctation.Length of legs I-III 723‒769, 637‒660 and 802‒848, respectively. IP = 1944–2239.Measurements are given in Table 1.

Leg segmentation formula: 7–7–7. Leg setal formula: Leg Ι: Ta– 1ω, 1ε, 2ζ, 27–28B; Ti– 2φ, 1κ, 14B; Ge– 1σ, 1κ, 8B; TFe– 5B; BFe– 3B; Tr– 1B; Cx– 1B (Figs. 2 A, 3A).

Leg ΙΙ: Ta– 1ω, 1ε, 2ζ, 25–26B; Ti– 2φ, 1κ, 15B; Ge–1σ, 1κ, 8B; TFe– 5B; BFe– 3B; Tr– 1B, Cx– 1B (Figs. 2B, 3B).

Leg ΙΙΙ: Ta– 1ζ, 25–26B; Ti– 1φ, 15B; Ge– 8B; TFe– 5B; BFe– 2B; Tr– 1B; Cx– 1B (Figs. 2C, 3C). Coxa III abnormally with two setae on left side. Tarsal claws slender, anterior and middle pointed, posterior with long onychotrichs.

Etymology — Name of the new species is derived from three small denticles on palpal tibial claw.

Type material — The holotype larva (ARS–20090703–1a) and paratype larvae (ARS–20090703–1b, 1c, 1d) were collected by Masoud Hakimitabar, under the stones (off host) from Damavand Mountain, Tehran Province, Iran, 9 July 2009. The specimens are deposited in Acarological Collection, Jalal Afshar Zoological Museum, Faculty of Agriculture, University of Tehran, Karaj, Iran.

Remarks — Leptus (L.) tridentatus Saboori, Hakimitabar & Khademi n. sp. is unique in having 3 denticles on dorsal side of palpal tibial claw. Also, it is unique in having the following combination of characters: palpal femur with one and palpal genu with two setae and basifemoral setae formula 3‒3‒2. There is one species, L. (L.) maldonadoicus with the basifemoral setae formula 3‒3‒2. It differs from L. (L.) maldonadoicus in the number of setae on palpal femur (1 vs. 2), number of setae between coxae I-II (6 vs. 0), number of setae between coxae II-III ($im$30–44 vs. 6), number of setae behind coxae III ($im$46–56 vs. 22), longer SD (109–126 vs. 64–$im$76), W (109–116 vs. $im$84–86), AW (87–94 vs. 74–76), PW (97–109 vs. 76), ISD (47–57 vs. 40–42), Ti I (144–180 vs. 106–112), Ti II (116–124 vs. 82–94), Ti III (188–215 vs. 130–134), leg I (723–769 vs. 484–502), leg II (637–660 vs. 394–406), and leg III (802–848 vs. 502–520). It is closely related to L. (L.) dubius (Paoli, 1937), L. (L.) pyrenaeus André, 1953, L. (L.) josifovi Beron, 1975, L. (L.) guus Haitlinger, 1990, L. (L.) mogadoranus Haitlinger, 1990, L. (L.) ogazulacus Haitlinger, 1990, L. (L.) pasopaicus Haitlinger, 1990, L. (L.) comosus Southcott, 1991, L. (L.) bertoldi Haitlinger, 1993, and L. (L.) batoricus Haitlinger, 1998, according to the setal counts on palpal genu and palpal femur. It differs L. (L.) dubius in the number of setae between coxae II (6–7 vs. 2), number of setae between coxae II & III ($im$30–44 vs. 8–10), shape of scutum, SD (109–126 vs. 90), W (109–116 vs. 90), AW (87–94 vs. 74), PW (97–109 vs. 81), Ti I (144–180 vs. 128), Ti II (116–131 vs. 96), and Ti III (188–215 vs. 154); from L. (L.) pyrenaeus in the number of setae between coxae II (6–7 vs. 2), number of setae between coxae II & III ($im$30–44 vs. 14–16), SD (109–126 vs. 57), W (109–116 vs. 83), AW (87–94 vs. 64), PW (97–109 vs. 79), AL (45–54 vs. 25), PL (42–47 vs. 25), 1b (60–64 vs. 110), 2b (22–30 vs. 80), and 3b (27–35 vs. 80); from L. (L.) josifovi in the number of setae between coxae II (6–7 vs. 2), number of setae between coxae II & III ($im$30–44 vs. 15), AL (45–54 vs. 63), 3b (27–35 vs. 45), and shape of scutum; from L. (L.) guus in the number of setae between coxae II & III ($im$30–44 vs. 20), SD (109–126 vs. 100–102), W (109–116 vs. 142–154), AW (87–94 vs. 124–132), PW (97–109 vs. 136–146), GL (176–210 vs. 244–288), Ti I (144–180 vs. 210), Ti II (116–131 vs. 186–192), and Ti III (188–215 vs. 324); from L. (L.) mogadoranus in the number of setae between coxae II (6–7 vs. 2), number of setae between coxae II & III ($im$30–44 vs. $im$20), shape of scutum, SD (109–126 vs. 82–92), W (109–116 vs. 134–146), AW (87–94 vs. 110–118), PW (97–109 vs. 122–130), Ti I (144–180 vs. 312), Ti II (116–131 vs. 254), and Ti III (188–215 vs. 362); from L. (L.) ogazulacus in the number of setae between coxae II (6–7 vs. 2), number of setae between coxae II & III ($im$30–44 vs. 22), shape of scutum, SD (109–126 vs. 80–82), W (109–116 vs. 100–102), AL (45–54 vs. 64–72), and PL (42–47 vs. 52–56); from L. (L.) pasopaicus in the number of setae between coxae II (6–7 vs. 2), number of setae between coxae II & III ($im$30–44 vs. 16), shape of scutum, SD (109–126 vs. 72), W (109–116 vs. 94), GL (176–210 vs. 142), ASens (47–52 vs. 40), and PSens (74–92 vs. 64); from L. (L.) comosus in the number of normal setae on basifemora (3-3-2 vs. 3-2-2), number of solenidia on TFe I (0 vs. 3), on TFe II (0 vs. 4), on Ge II (1 vs. 4–5), on TFe III (0 vs. 6–7), on Ge III (0 vs. 6), longer leg I (723–769 vs. 590), leg II (637–669 vs. 540), and leg III (802–848 vs. 600); from L. (L.) bertoldi in the number of setae between coxae II (6–7 vs. 2), shape of scutum, SD (109–126 vs. 66–68), SD ≥ W in L. (L.) tridentatus Saboori, Hakimitabar & Khademi n. sp. (vs. SD < W in L. (L.) bertoldi), AL (45–54 vs. 70), PL (42–47 vs. 60–62), 1b (60–64 vs. 90), GL (176–210 vs. 244), Ti I (144–180 vs. 332), Ti II (116–131 vs. 258–264), and Ti III (188–215 vs. 384); from L. (L.) batoricus in the number of setae between coxae II (6–7 vs. 2), number of setae between coxae II & III ($im$ 30–44 vs. $im$18), Ti I (144–180 vs. 114), Ti II (116–131 vs. 100), and Ti III (188–215 vs. 150), fD ($im$170–204 vs. 86), number of setae behind coxae III ($im$46–56 vs. $im$32).

Examination of type specimens showed that some meristic data provided in the descriptions of Haitlinger (1986) and Haitlinger & Saboori (1996) should be amended and completed.

Abrolophus khanjanii was described by Haitlinger & Saboori (1996) based on a single specimen. We re-examined the holotype and present amended data as follows: Leg setal formula: Leg Ι: Ta– 1ω, 1ε, 2ζ, 1Cp, 22B; Ti– 2φ, 1κ, 13B; Ge– 1κ, 1σ, 11B; TFe– 8B; BFe– 4B; Tr– 2B; Cx– 1B.

Leg ΙΙ: Ta– 1ω, 2ζ, 1Cp, 19B; Ti– 2φ, 13B; Ge– 1κ, 1σ, 9B; TFe– 5B; BFe– 4B; Tr– 2B, Cx– 1B .

Leg ΙΙΙ: Ta– 1ζ, 20B; Ti–13B; Ge– 1σ, 9B; TFe– 5B; BFe– 4B; Tr– 2B; Cx– 1B.

Palpal tarsus with 8 setae and gnathosoma with two pairs of hypostomalae and one pair of galealae. Palpal femur with one projection whereas in figure 18 of original description, the projection was shown on palpal genu.

It was described by Haitlinger in 1986 and redescribed by Haitlinger & Sundic (2015). We checked the holotype and present amended data in the redescription here.

Leg setal formula: Leg Ι: Ta– 1ω, 1ε, 1Cp, 2ζ, 25B; Ti– 1Cp, 2φ, 1κ, 13B; Ge– 1κ, 1σ, 11B; TFe– 7B; BFe– 4B; Tr– 2B; Cx– 1B.

Leg ΙΙ: Ta– 1ω, 1Cp, 2ζ, 20B; Ti– 2φ, 12/13B; Ge– 1κ, 1σ, 9B; TFe– 5B; BFe– 4B; Tr– 2B, Cx– 1B.

Leg ΙΙΙ: Ta– 1ζ, 20B; Ti–13B; Ge– 1σ, 9B; TFe– 5B; BFe– 4B; Tr– 2B; Cx– 1B.

Palpal tarsus with 8 setae and gnathosoma with two pairs of hypostomalae and one pair of galealae.

ASens bases in level with AL bases.

The authors are thankful to Prof. Ryszard Haitlinger for providing type specimens and to Prof. Joanna Mąkol for her kind help during our stay in Poland. The project (Invited Collaborative Research Program) on which this paper was based was supported by a grant (No. 1724) from the “Center for International Scientific Studies and Collaboration”, Ministry of Science, Research and Technology of Iran which is greatly appreciated.

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