Paratrombicula philippii, 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 : 18-19

Paratrombicula philippii sp. nov.

(Figs. 10, 11)

Diagnosis. SIF = 7B-N-3-2111.1000; fsp = 7.7.7; fCx = 1.1.1; fSt = 2.2; fPp = B/B/BNB; fSc: PL = AM = AL; Ip = 700–716; fD = 2H-8(9)-8(9)-7(9)-4(7)-…; DS = 37–38; VS = 30; NDV = 67–68. Standard measurements of holotype and paratype (in parentheses): AW 59 (59), PW 77 (81), SB 23 (27), ASB 23 (23), PSB 27 (31), SD 50 (54), P-PL 22 (22), AP 29 (30), AM 27 (32), AL 36 (33), PL 29 (32), S (63), H 34 (37), D min 27 (29), D max 35 (36), V min 26 (23), V max 32 (35), pa 254 (243), pm 218 (220), pp 245 (238), Ip 716 (700), DS 37 (38), VS 30 (30), NDV 67 (68), TaIIIL 62 (59), TaIIIW 14 (14), m-t 0.348 (-).

FIGURE 10. Paratrombicula philippii sp. nov. A, dorsal idiosomal setae of 1st row (holotype); B, preanal ventral idiosomal seta (holotype); C, scutum and eyes (holotype); D, arrangement of dorsal idiosomal setae (paratype); E, arrangement of ventral idiosomal setae (paratype). Scale bars: 20 Μm (A, B), 50 Μm (C), 100 Μm (D, E).

Description (larva). IDIOSOMA. Eyes 2 + 2, on ocular plate. One pair of humeral setae, 35–36 dorsal idiosomal setae covered with rather long barbs, fD = 2H-8-8-7-4-6-2 (holotype), 2H-9-9-9-7-2 (paratype); 4 sternal setae; 30 ventral setae; total number of idiosomal setae excluding coxal and sternal 67–68.

GNATHOSOMA. Cheliceral blade with tricuspid cap; gnathobase sparsely covered with large puncta and bears one pair of branched setae; galeala nude; palpal claw with 3 prongs; seta on palpal femur branched; seta on palpal genu with one branch; dorsal palpal tibial seta branched; lateral palpal tibial seta nude; ventral palpal tibial seta branched; palpal tarsus with 7 branched setae and basal tarsala.

SCUTUM. Pentagonal, with angulated posterior margin, densely covered with small puncta; AM base slightly posterior to level of ALs; SB clearly anterior to level of PLs (PSB—P-PL = 5–9); all scutal setae of about same length (PL = AM = AL); flagelliform sensilla with about 8 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, 2 genualae, microgenuala; tibia 8B, 2 tibialae, microtibiala; tarsus 22B, tarsala 14 long, microtarsala near and slightly proximal 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, 16 long, microtarsala behind tarsala, pretarsala. Leg III: coxa 1B; trochanter 1B; basifemur 2B; telofemur 3B; genu 3B, genuala; tibia 6B, tibiala; tarsus 14B, mastitarsala with numerous long cilia.

Host. Liolaemus nigromaculatus (Wiegmann) .

Type material. Holotype larva ( ZIN collection No. 8445, T-Tr.-71) ex Liolaemus nigromaculatus No. 31, CHILE: Coquimbo Region, Limarí Province, Fray Jorge National Park, 10 December 2010, coll. D. González- Acuña & S. Muñoz-Leal; paratype larva (8444) with same data.

Etymology. The species is named after Rodolfo Amando Philippi, a German and Chilean naturalist who made a valuable contribution to the knowledge of Chilean nature.

Remarks. Paratrombicula philippii sp. nov. is the first known Paratrombicula species having mastitarsala. However, this seta is ciliated in P. philippii and therefore can be regarded as a typical tactile seta. By the presence of 2 genualae I, P. philippii differs from all other Paratrombicula (having only 1 genuala I) except P. goff i Stekolnikov and González-Acuña, 2012, in which some part of examined specimens has 2 or 1/2 genualae I. Moreover, the new species is very close to P. goffi by the measurable characters and differs from it in the presence of 7–9 setae in 2nd and 3rd rows of dorsal idiosomal setae vs. 6, larger number of idiosomal setae (DS = 37–38 vs. 28–32, VS = 30 vs. 20–26, NDV = 67–68 vs. 50–57), and in slightly shorter legs (Ip = 700–716 vs. 725–765).