Synaptothrips paradoxus (Bagnall, 1919)

Thripinae, Thripidae, Terebrantia, Thysanoptera

Figures

Fig. 1: Pedicel and segments III and IV with forked sense cone, 9-segmented antenna
Fig. 2: Head dorsal with ocellar triangle
Fig. 3: Pronotum
Fig. 4: Meso- and metanotum
Fig. 5: Meso- and metasternum
Fig. 6: Fore wing and fore wing distal region
Fig. 7: Tergites I and II
Fig. 8: Sternites VI and VII
Fig. 9: Tergites VII and VIII
Fig. 10: Tergites VII-XI
Fig. 11: Tergites VIII and IX

Synaptothrips paradoxus breeds in the flowers of certain Protea species (sugar bushes). Female macropterous. Body color mainly brown; fore femora distally, fore tibia and all tarsi yellowish; antennal segments I & II brown, III-IX shaded yellow-brown; fore wings light brown. Antennae 9-segmented; segment VI with apex separated by complete suture; III & IV with forked sense cone (Fig. 1). Head slightly wider than long; without sculpture between eyes; 3 pairs of ocellar setae present, pair III arising on anterior margin of ocellar triangle posterior to first ocellus, pair III as long as side of ocellar triangle, pair I & II not as long as side of ocellar triangle, pair II arising almost lateral to first ocellus; postocular setae in a single row and about as long as hind ocellus (Fig. 2). Pronotum with many discal setae and 2 pairs of long posteroangular setae; posterior margin with 4-5 pairs of setae (Fig. 3). Metanotum closely striate, transverse at anterior and longitudinal at posterior; median setae short and arising close to posterior margin; campaniform sensilla present (Fig. 4). Mesofurca with spinula (Fig. 5). Mid and hind tarsi 2-segmented. Fore wing first and second vein with complete row of setae (Fig. 6). Tergite VIII with group of microtrichia anteromesad to spiracle, but no posteromarginal comb (Fig. 9); tergite X with median dorsal setae stout and thorn-like (Fig. 10 and 11). Sternite II with 1 discal seta medially, remaining sternites without discal setae; sternite II with 3 or 4 pairs of marginal setae, III-VI with 4 or 5 pairs, VII with 3 pairs of which pair S1 arises in front of margin (Fig. 8).
Male unknown.

The genus Synaptothrips Trybom, 1910
This genus includes 11 species, all from southern Africa (Mound 1968). A first description is given by Trybom (1910). They have been collected mainly within Cape Province, and are possibly all associated with members of the flowering plant family Proteaceae. Members of the genus have 7-9 antennal segments (depending on a partial or complete suture of antennal segment VI), antennal segments III & IV with forked sense cone, head with 3 pairs of ocellar setae, pronotum with 2 pairs of posteroangular setae, fore wings with an almost complete row of setae on both veins, sternites II-VI with 3 or more pairs of posteromarginal setae, and several species have a single discal seta on sternite II (Mound 1968). The members of Synaptothrips are unusual in having the median pair of metanotal setae arising on the posterior half of this notum, in contrast to almost all other Thripidae.

It differs from the related species Synaptothrips distinctus in having a brown body color, light brown fore wings, ocellar setae II on head arising almost lateral to first ocellus and they are not as long as side of ocellar triangle, ocellar setae III arising on anterior margin of ocellar triangle and posterior to first ocellus, ocellar setae III are as long as side of ocellar triangle, and the median dorsal setae on tergite X are stout and thorn-like. Synaptothrips distinctus has a mainly pale or yellow body color, uniformly pale fore wings, ocellar setae II on head arising anterior to first ocellus close to the base of antennae and they are as long as side of ocellar triangle, ocellar setae III arising well outside ocellar triangle and almost lateral to first ocellus, ocellar setae III are as long as distance between compound eyes, and all setae on tergite X are elongate and slender.
Compared to the species of Synaptothrips with 9-segmented antennae and median pair of metanotal setae arising on the posterior half of this sclerite, all other Thripidae have 7- or 8-segmented antennae (except Anaphothrips obscurus with 8- or 9-segmented antennae) and metanotal median setae arising at anterior margin or on the anterior half of this sclerite.

Life history
As with other thrips species the life cycle from egg to adult is dependent on temperature. The full cycle can take about 15 days (Lewis 1973) to over a month and adults may live for more than one month producing several generations in one year depending on seasonal weather. With greenhouse temperatures the developmental time from egg to adult can decrease to about one week.

Host plants
Protea sp. (sugar bushes) - Protea barbigera, Protea laurifolia. In Ethiopia, thrips belonging to genus Synaptothrips are reported as pest of Niger (Bayeh & Gebrre Medhin 1992).

Vector capacity
None identified, but possible mechanical distribution of phytopathogenic fungi and bacteria.

Damage and symptoms
-

Detection and control strategies
-

Biogeography

East Africa. Tanzania (Kilimanjaro - Mawenzi, Boismarckburg).

Bagnall RS (1919). Brief descriptions of new Thysanoptera - X. Annals and Magazine of Natural History, Zoology, Botany and Geology. (Serie 9) 4: 253-277

Bayeh M & Gebre Medhin T. (1992). Insect pests of Niger, linseed and Brassica. pp. 174-177 in Oilseed Research and Development in Ethiopia. Proceedings of the First National Oilseed Workshop, 3-5 December 1991, Addis Abeba

Lewis T (1973). Thrips: Their biology, ecology and economic importance. Academic Press Inc., London Ltd., 349 pp

Mound LA (1968). A review of R. S. Bagnalľs Thysanoptera collections. Bulletin of the British Museum (Natural History), Entomology. Supplement 11: 1-181

Mound LA (1968). New synonymy in the South African genus Synaptothrips Trybom (Thysanoptera) with a key to the species. Journal of the Entomological Society of South Africa. 31 (1): 87-95

Trybom F (1910). Physapoda. In Denkschriften der Medizinisch-Naturwissenschaflichen Gesellschaft zu Jena. Bd. 16, Schultze L. Zoologische und anthropologische Ergebnisse einer Forschungreise im westlichen und zentralen Südafrika (1903-1905). 4: 147-174 (pp 156-158)