Typhlodromus (Anthoseius) mathieui Kreiter and Chatti, 2017

Chatti, A., Kreiter, S., Lebdi-Grissa, K. & Ksantini, M., 2017, Phytophagous and predatory mites on olive trees in Tunisia. Catalogue, description of one new species and key for identification (Acari, Eriophyidae, Tetranychidae, Tenuipalpidae and Phytoseiidae), Acarologia 57 (2), pp. 233-254 : 242-246

Typhlodromus (Anthoseius) mathieui Kreiter and Chatti n. sp.

Zoobank: 445F995C-A657-4114-9E7B-AF7755087D69

Material examined — Sfax: Cap Bon: Grambalia (36°36’46.35"N, 10° 31’30.59"E), April 2009, March 2010 and October 2011, 4 ♀♀ on Arbequina and Koroneiki varieties in a very high density olive orchard. The four females were collected from foliage of olive tree infested with eriophyid mites .

Diagnose — This species has five solenostomes, all dorsal setae smooth except Z5, peritreme extending between j1 and j3, two setae inserted on the sternal shield, one on a metasternal shield and one on the membrane, four setae on the ventrianal shield with no preanal solenostome, 3 macrosetae slightly knobbed, a spermatheca pocular, 3 teeth on the fixed digit and 2 teeth on the movable digit of the chelicara. This is a unique combination of characters which clearly distinguish this species from all other species within the genus Typhlodromus subgenus Anthoseius . This new species is more close to T. (A.) aestivalis Athias-Henriot, 1960 but this latter species has setae with different length, setae St4 on a small metasternal shield (not for the new species), three knobbed macrosetae but with STiIV and SGeIV more than 40 µm and the shape of the spermathecal is very different. It resembles also to T. (A.) clairathiaseae Wainstein & Arutunjan, 1967 but setae have different length, setae St4 on a small metasternal shield (not for the new species), this species has only knobbed macrosetae on the basitarsus IV and the shape of the spermatheca is very different. The new species is also closed to T. (A.) maspalomensis Ferragut & Peaea-Estévez, 2003 but setae lengths are very different, setae St4 on a small metasternal shield (not for the new species), ventrianal shield and spermatheca with different shape and only two pairs of macrosetae knobbed on the three pairs present in this species. Finally, it resembles also to T. (A.) macrum Ke & Xin, 1983 and to T. (A.) rapidus Wainstein & Arutunjan, 1968 but these two species have pores on the ventrianal shield, only one macroseta on leg IV and a spermatheca with a totally different shape.

Description of the adult female (n= 4) ( Figs. 1- 3 )

Dorsum ( Fig. 1 ) — Dorsal shield 377 (352 – 402) long and 179 (178 – 180) wide, slightly reticulated anteriorly, with five solenostomes (gd2, gd4, gd6, gd8 and gd9), 11 pairs of poroids, 18 pairs of dorsal setae and two pairs of sub-lateral setae: j1 27 (26 – 28), j3 29 (28 – 30), j4 15, j5 16 (15 – 17), j6 18 (16 – 20), J2 24 (23 – 25), J5 9 (8 – 10), z2 19 (18 – 21), z3 24 (23 – 25), z4 23 (22 – 24), z5 16 (15 – 18), Z4 45 (43 – 47), Z5 60 (50 – 70), s4 27 (26 – 28), s6 29 (28 – 30), S2 35 (33 – 37), S4 34 (33 – 37), S5 22 (20 – 25), r3 26 (25 – 28), R1 25. All setae smooth except Z5 which is slightly serrated.

Peritreme ( Fig. 1 ) — Extending between j1 and j3.

Venter ( Fig. 2 ) — All shields slightly reticulated. Sternal shield with two pairs of setae and two pairs of pores; one pair of sternal setae on a small metasternal shield and one pair on the membrane; posterior margin convex. Distances between st1-st3 70, st2-st2 60, st5-st5 53 (52 – 54). Two pairs of metapodal shields 28 long and 8 wide for the larger and 17 long and 3 wide for the slender shield. Ventri-anal shield with four pairs of preanal setae (JV1, JV2, JV3 and ZV2), and no pre-anal solenostome but small pores very close in the center. Membrane surrounding ventri-anal shield with four pairs of setae (ZV1, ZV3, JV4 and JV5), and five pairs of round to oblong poroids; ventri-anal shield 116 (113 – 120) long, 103 wide at level of anterior corners (ZV2), and 90 wide at level of anus. JV5 52 (50 – 53) long.

Chelicera ( Fig. 3 a ) — Fixed digit 33 long with 3 teeth; and movable digit 30 long with 2 teeth. Pilus dentilis visible on all chelicerae of the four females.

Spermatheca ( Fig. 3 b ) — Spermatheca pocular ( Denmark et al. 1999), with an elongate cervix 22 long and 15 wide, a small neck at the basis of the cervix and an atrium at the end of this small neck. Visible ducti minor and major.

Legs ( Fig. 3 c ) — Legs IV with three macrosetae slightly knobbed on the basitarsus, tibia and genu. SGeIV 27 (26 – 28), STiIV 27 (26 – 28), STIV 59 (58 – 60). Genu II and III with 7 setae each. Chaetotactic formula of genu II: 0-2/1, 2/0-2; genu III: 1-1/0, 2/1-2. Length of leg I: 320 (315 – 325), II: 267 (263 – 270), III: 276 (274 – 278), IV: 383 (353 – 313).

Type material — the holotype female and two paratype females deposited in Montpellier SupAgro – INRA Acarology collection, Montpellier, France ; one paratype female deposited in the mite reference collection of the entomology laboratory of Institut de l’Olivier (Sfax, Tunisia) .

Etymology — The name " mathieui " refers to the son of Serge Kreiter, Mathieu Kreiter.

Remarks — The combination of characters of this new species clearly distinguishes it from the other species in the genus Typhlodromus , subgenus Anthoseius . However, it relates very well with a species that Athias Henriot (1960a) described based on a single male from Algeria collected from Ranunculus sp. As males lack in our samples, we obviously could not confirm if the species presently described resembles the latter and we therefore decided to describe it as a new species. A search for males on olive trees will continue in the hope to find males and more females to ensure the identity of the presently described species and perhaps consequently the status of the species described by Athias-Henriot based on only one male.

Figures

FIGURE 1: Dorsal shield and peritreme of the female of Typhlodromus (Anthoseius) mathieui n. sp.

FIGURE 2: Ventral shields of the female of Typhlodromus (Anthoseius) mathieui n. sp.

FIGURE 3: Calyx of the spermatheca (a), Chelicera (b) and Macrosetae on leg IV (c) of the female of Typhlodromus (Anthoseius) mathieui n. sp.