Tetranychus palmidectes, Flechtmann, 2010

Flechtmann, C. H. W., 2010, Description Of Two New Tetranychoid Mite Species (Acari, Prostigmata) From Guadeloupe, French Antilles, Acarologia 50 (1), pp. 5-11 : 8-11

Tetranychus palmidectes n. sp.

( Figures 3 and 4 )

Diagnosis — Female with dorso hysterosomal striae longitudinal between members of the third and the fourth pairs of dorsocentral setae setae, forming a diamond shaped pattern; tarsus I with one tactile seta proximal to and three tactile setae in line with proximal duplex setae; empodium with a large dorsomedian spur, more than half as long as proximoventral hairs; area immediately anterior to genital cover devoid of striae.

Male — aedeagus with ventral margin evenly curved dorsad, the terminal knob slightly wider than its stem and with anterior and posterior angulations acute.

Female — (n = 10). Gnathosoma: peritremes strongly hooked ( Figure 4D ); palp tarsus with terminal sensillum (spinneret) thick, about as long as broad ( Figure 3E ); stylophore rounded anteriorly; buccal cone with anterior adoral setae spinelike; second pair conspicuous, blade shaped; third pair minute, barely noticeable, probably due to its more dorsal insertion ( Figure 3F ). Dorsal body setae finely serrate, long; lengths: V2 68-75, 68-75 apart; Sc1 131-143, 86-94 apart; Sc2 90-98; c1 113-124, 60- 71 apart; c2 105-124; c3 109-120; d1 113-124, 94-101 apart; d2 120-128; e1 113-120, 30-49 apart; e2 113- 124; f1 90-101, 26-49 apart; f2 75-79; h1 38-45, h2 38-45. Dorsal integumental striae longitudinal between members of setae e1 and members of setae f1 (third and fourth pairs of dorsocentral setae), forming a diamond shaped pattern. Area immediately anterior to genital area smooth, devoid of striae ( Figure 3G ). Leg chaetotaxy, solenidia in parentheses, alternative count in brackets, from coxae to tarsi: I — 2-1-9[10]-5-9(1)-13(1) + 2 duplexes; II — 2-1-6-5-7-13(1) + 1 duplex; III — 1-1-4-6-9[10](1); IV — 1-1-4-4-7-10(1). Tarsus I with one tactile seta proximal to proximal duplex setae and three tactile setae almost in line with proximal duplex setae ( Figure 3A ); empodium split into three pairs of proximoventral hairs and with a dorsomedian spur, longer than half the length of proximoventral hairs ( Figure 3C ); tarsus II with three tactile setae and one solenidion proximal to duplex seta and one tactile seta near duplex setae ( Figure 3B ); empodium similar to empodium I, as well as III and IV.

Idiosoma 326-412, body including rostrum 420-

Flechtmann C.H.W.

506; widest shortly behind level of setae c3, 244-319 wide.

Male — (holotype and 6 paratypes). Gnathosoma: palpus with terminal sensillum (spinneret) short, slightly conical, smaller than that of female

( Figure 4C ).

Leg chaetotaxy, solenidia in parentheses, from coxae to tarsi: I — 2-1-9-5-8(4)-12(4) + 2 duplexes; II — 2-1-6-5-7-14(1) + 1 duplex; III — 1-1-4-4-6-9(1); IV — 1-1-4-4-7-10(1). Tarsus I with two solenidia and two tactile setae situated proximal to proximal duplex setae, one solenidion and one tactile seta almost in line with proximal duplex setae ( Figure 4A ); empodium I a robust trifid plate with a well developed mediodorsal spur ( Figure 4A ). Tarsus II with one solenidion and four tactile setae proximal to duplex setae ( Figure 4B ); empodia II-IV split into three pairs of proximoventral hairs and with a well developed dorsomedian spur ( Figure 4B ). Aedeagus with broad shaft, curved evenly dorsad, the terminal knob slightly wider than stem and with anterior and posterior angulations acute ( Figure 4E ).

Etymology — the specific designation palmidectes is derived from palm tree plus the Greek dektes, dektikos, meaning able to bite, that is, palm leaf puncturing, feeding.

Type material — holotype male, 6 male and 19 female paratypes, from leaves of the ruffled fan palm, Licuala grandis H. Wendl. (Arecaceae) , Lamentin, Ravine Chaude, Guadeloupe, coll. J. Étienne, 19 October 2007, on 19 microscopic preparations in the collection of Departamento de Entomologia e Acarologia, Escola Superior de Agricultura "Luiz de Queiroz", Piracicaba, SP, Brazil.

Remarks — T. palmidectes n. sp. is to be placed in group 6 of Tetranychus species as defined by Flechtmann and Knihinicki (2002). The host plant is an ornamental palm originating from Vanuatu ( New Hebrides) and New Guinea and is cultivated mainly in umbrofilous environments.

Together with this spider mite, specimens of a predacious mite, Neoseiulus longispinus (Evans, 1952) ( Mesostigmata : Phytoseiidae ) were collected. Species identified by Gilberto J. de Moraes who reported it previously from Guadeloupe ( Moraes et al., 2000).

Figures

FIGURE 3: Tetranychus palmidectes n. sp. Female. A - tibia and tarsus I; B - tibia and tarsus II; C - ambulacrum tarsus I; D - ambulacrum tarsus IV; E - palp; F - buccal cone, ventral; G - area anterior to genital coverflap, ag - ag genital seta; g1 - genital setae 1.

FIGURE 4: Tetranychus palmidectes n. sp. Male. A - tibia and tarsus I, ambulacrum enlarged; B - tibia and tarsus II, ambulacrum enlarged; C - palp; D - peritreme; E - aedeagi, left of holotype.