Haplothrips acaciae, Mound & Minaei, 2007

Mound, Laurence A. & Minaei, Kambiz, 2007, Australian thrips of the Haplothrips lineage (Insecta: Thysanoptera), Journal of Natural History 41 (45 - 48), pp. 2919-2978 : 2944-2945

Haplothrips acaciae sp. nov.

Female macroptera. Body colour light brown to brown, mid and hind tarsi brownish yellow, fore tarsi and basal half of antennal segment III yellow; major setae weakly shaded, fore wing shaded at base, then pale but variably shaded medially and distally. Head as broad as long, maxillary stylets wide apart, retracted to postocular setae, maxillary bridge complete ( Figure 9 ); postocular setae capitate, extending beyond posterior margin of compound eyes. Antennal segments III–IV each with two sensoria; segment VIII distinctly constricted at base (Figure 16). Pronotum with five pairs of long, capitate setae. Metanotum reticulate medially, median setae arise on anterior half of sclerite. Mesopresternum transversely boatshaped but slender medially. Fore tarsal tooth small, acute, directed forwards. Fore wing with about five duplicated cilia, sub-basal setae capitate. Tergite II ( Figure 11 ) with wingretaining setae weak, III–VII with anterior pair weaker than posterior pair; posteromarginal setae S1 long and capitate on tergites II–VII, but shorter on VIII; tergite IX setae S1 bluntly pointed, S2 finely acute.

Measurements of holotype female (in M m). Body length 1520. Head, length 145; median width 155; postocular setae 30. Pronotum, length 110; width 200; major setae am 30, aa 24, ml 36, epim 48, pa 42. Fore wing length 560; sub-basal setae 34, 40, 52. Tergite IX setae S1 55, S2 75, S3?. Tube length 100; basal width 55; anal setae 120. Antennal segments III–VIII length 24, 42, 44, 40, 36, 24.

Male macroptera. Similar to female, fore tarsal tooth slightly larger; tergite IX setae S2 short and stout; apex of pseudovirga narrowly spoon-shaped.

Measurements of paratype male (in M m). Body length 1300. Head, length 140; median width 130; postocular setae 25. Pronotum, length 100; width 175; major setae am 25, aa 30, ml 35, epim 44, pa 40. Fore wing length 400; sub-basal setae 30, 35, 45. Tergite IX setae S1 40, S2 20, S3 75. Tube length 75; basal width 40; anal setae 90. Antennal segments III– VIII length 30, 30, 40, 38, 35, 30.

Material examined

Holotype ♀ macroptera: South Australia, Middleback , 30 km NW of Whyalla, from Acacia papyrocarpa phyllodes webbed by spider, 18 March 1996 (LAM 3008) . Paratypes: 8♀, 1 „ collected with holotype; 7♀, 1 „ same locality, 29 December 1997 ; 5♀, 5 „ with larvae, same locality, 4 May 1995. Western Australia, 108 km S of Newman , 6♀, 4 „ with larvae, in phyllodes webbed by?Lepidoptera larvae, 21 April 1997. New South Wales, Baldranald 20 km W, 1 „ in old gall, 6 May 1995; 10 km N of Peak Hill , 2♀ from Callitris , 8 December 2001. Queensland, Aramac 37 km NE , 2♀, 1 „ from old spider nest of phyllodes on Acacia microcephala , 31 April 1998.

Comments

On four occasions colonies of this species have been taken from webbed phyllodes of Acacia species , and at three of these sites the webbing was certainly produced by spiders not by Lepidoptera (for the fourth sample the field notes remain equivocal). Despite this association, it is not known if the species is predatory or phytophagous. It is one of only two known species in Haplothrips with two sensoria on both the third and fourth antennal segments.

Haplothrips anceps Hood

Haplothrips anceps Hood 1918, p 129 .

Haplothrips angustus Hood 1919, p 77 . syn. n.

No consistent differences have been found between specimens, including type specimens, identified as H. anceps and as H. angustus , despite the statement by the original author that the latter species has longer antennal segments. Pitkin (1973) suggested that there was a difference in the length/width ratio of the third antennal segment (1.3–1.8 in anceps , but 1.8–2.2 in angustus ), but this does not appear to be a satisfactory discriminant because of the variation within individual field samples. Moreover, it does not correlate satisfactorily with any other structural differences, such as the form of setal apices, and the male genitalia of the two forms are identical. Although treated here as one species, specimens from northern Australia commonly have the third antennal segment rather shorter ( anceps -form) than specimens from southern Australia ( angustus -form), but some genetic differences are to be expected between populations spread over an area from Adelaide to Cape York. In structure this species is closely similar to H. victoriensis , and the male pseudovirga of these species cannot be distinguished satisfactorily. This group of common thrips requires more detailed study, with particular attention to the host plants on which breeding occurs. In southern Australia H. anceps appears to be associated with flowering sedges such as Eleocharis (Cyperaceae) , but samples are often taken from various Poaceae . The host records from northern Australia are less clear.

Recognition

Body and legs dark brown, mid and hind tarsi brownish yellow, fore tarsi and apex of fore tibiae yellow, at least basal half of antennal segment III yellow, IV light brown; pronotal major setae weakly shaded; fore wings pale except at base. Head with maxillary stylets about one-third of head width apart ( Figure 10 ). Antennal segment III with one sensorium, IV with four. Pronotum with five pairs of capitate setae, am setae short; mesopresternum transverse and boat-shaped. Fore tarsal tooth in female minute but variably large in male. Metanotum weakly reticulate medially, median setal pair arising on anterior half; fore wing sub-basal setae S1 and S2 capitate, S3 capitate or pointed; about eight duplicated cilia present. Pelta triangular ( Figure 12 ); tergite IX setae S1 and S2 blunt. Male pseudovirga with apex spoon-shaped (Figure 29).

Measurements of one female (in M m) (Northern Territory, Daly River, May 2002). Body length 1980. Head, length 165; median width 155; postocular setae 28. Pronotum, length 130; width 240; major setae am 22, aa 18, ml 18, epim 38, pa 30. Fore wing length 700; subbasal setae 28, 28, 40. Tergite IX setae S1 62, S2 70, S3 90. Tube length 105; basal width 55; anal setae 145. Antennal segments III–VIII length 38, 44, 40, 34, 32, 20.

Figures

Figures 1–15. (1) Bagnalliella nigricoxae, holotype. (2) Dyothrips pallescens, pronotum. (3) Dolichothrips reuteri, mouth cone. (4) Androthrips monsterae, fore femora. (5) Priesneria peronis, antenna. (6) Karnyothrips melaleucus, head, pronotum, and fore legs. (7) Euoplothrips bagnalli, fore legs of small and large males. (8) Mesothrips jordani, head. (9) Haplothrips acaciae, head and pronotum. (10) H. anceps, head, pronotum, and right fore leg. (11) H. acaciae, pelta. (12) H. anceps pelta. (13) H. angusi pelta. (14) H. avius, head. (15) H. angusi, prosternites.