Figures
Fig. 1: Antenna (inset: I. - III. antennal segment)
Fig. 2: Head dorsal with ocellar triangle
Fig. 3: Pronotum
Fig. 4: Meso- and metanotum
Fig. 5: Fore- and hindwing, base of fore wing with alula
Fig. 6: Sternites V and VI
Fig. 7: Tergites VI and VII
Fig. 8: Tergites VIII and IX
Taxonomic Information
Species:
Psydrothrips luteolus Nakahara & Tsuda, 1994
Common name:
Syngonium thrips
Present taxonomic position:
Family: Thripidae Stephens, 1829
Subfamily: Thripinae (Stephens) Karny, 1921
Genus: Psydrothrips Palmer & Mound, 1985
Species Recognition
General information about the genus Psydrothrips:There are two species known in this genus both exhibit nine segmented antennae with forked sense cones on segments III and IV, there are three ocellar setae, two long setae on the pronotum, the forewing contains a few widely spaced setae on the first vein and a complete row of evenly spaced setae on the second vein. In addition, tergite VIII contains a complete marginal comb of long microtrichia.
Typical character states of Psydrothrips luteolus:
Body color
Mainly pale or yellow, with some darker markings
Antennae
Number of antennal segments: 9
Segment IV - forked sensorium: extending to a point at least 30% distal to base of segment V
Segments II and III shape: more or less symmetric
Segments III & IV sensoria: emergent and forked
Base of sensorium on antennal segment VI: no more than 2 times as wide as base of nearest seta
Terminal antennal segments: rarely elongate
Head:
Distance between bases of ocellar setae III: greater than width of first ocellus
Head shape between compound eyes: distinctly prolonged
Major postocular setae: more than half as long as ocellar setae III
Ocellar setae III on head: arising on anterior margin of, or in front of, ocellar triangle
Surface of head, pronotum and fore legs: without strong reticulate sculpture
Ocellar setae I in front of anterior ocellus: present
Prothorax
Number of pairs of elongate pronotal setae: 0-3
Number of pairs of elongate posteroangular pronotal setae: 1
Pronotum shape: rectangular
Mesothorax
Mesothoracic endofurca: without median spinula
Metathorax
Metanotal median area sculptured lines:with mainly equiangular reticulation
Metanotal median setae position: arising behind anterior margin
Metanotum: with campaniform sensilla
Metanotum major sclerite: with two major sclerites, metascutum and metascutellum
Metanotum median area: with at least some equiangular reticulation
Metanotum sculpture: without dominant sculptured triangle medially
Metathoracic endofurca: transverse, sometimes with simple median spinula
Wings
Wings: present and more than half as long as abdomen
First vein of forewing: distinct from costal vein
Forewing anterior margin: with setae and cilia but cilia longer than setae
Forewing color: uniformly light brown
Forewing costal fringe of cilia: arising at anterior margin of wing
Forewing costal setae at middle of wing: shorter than median width of wing
Forewing first vein setal row: incomplete, with setae not closely and uniformly spaced
Forewing posterior margin cilia: undulated near apex
Forewing second vein setal row: complete, with setae closely and uniformly spaced
Forewing surface: not reticulate
Forewings: with veins, setae and microtrichia
Legs
Fore tibial apex: not extending around fore tarsus - with small curved claw ventrolaterally
Mid and hind tarsi: with two segments
Abdomen:
Abdominal pleurotergites: not covered in microtrichia
Abdominal segment X: never tubular, longitudinally incomplete ventrally in both sexes
Abdominal sternite II: with 1 or 2 discal setae in addition to marginal setae
Abdominal sternite III of female: without glandular areas
Abdominal sternite VII: with marginal setae but no discal setae
Abdominal sternite VII median marginal setae: arising at margin
Abdominal sternites IV , V and VI: with discal setae present medially as well as marginal setae
Number of lateral marginal setae on abdominal tergite II: 3
Abdominal tergites: without curved wing-retaining setae
Abdominal tergites IV & V median setal pair: much shorter than distance between their bases
Abdominal tergites V-VII: without paired ctenidia, sometimes with irregular microtrichia
Number of discal setae on sternite V: 3-13
Setae on abdominal tergite X: slender
Surface of lateral thirds of abdominal tergites: with many regular rows of fine microtrichia
Ctenidia on tergite VIII: not present, but groups of microtrichia
Tergite VIII posteromarginal comb of microtrichia: present, complete medially
Tergite VIII posteromarginal microtrichia: long, slender and regular
Biology
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 to over a month and adults may live for more than one month producing several generations in one year depending on seasonal weather (Lewis, 1973). With greenhouse temperatures the developmental time from egg to adult can decrease to about one week.
Host plants:
Dieffenbachia, Epipremnum, Syngonium
Vector capacity:
None identified
Current known distribution:
North America
Additional notes:
This specie is known to damage the
developing young leaves of its host plants.
Bibliography
Lewis, T. (1973): Thrips their biology, ecology and economic importance. Academic Press Inc., London Ltd. 349 pp.
Moritz, G., D. Morris, and L. A. Mound (2002): ThripsID: Visual and molecular identification of pest thrips of the world, pp. 93. CSIRO Publishing.
Moritz, G., M. L. A. Mound, D. C. Morris, and A. Goldarazena (2004): Pest Thrips of the World visual and molecular identification of pest thrips. An identification and information system using molecular and microscopical methods. CSIRO Canberra, Australia.
Mound, L. A., and R. Marullo (1996): The thrips of Central
and South America: An Introduction (Insecta: Thysanoptera). Associated
Publishers, Gainesville.
Nakahara, S & Tsuda, D (1994): Psydrothrips
luteolus, New Species, from Hawaii and notes on P. kewi (Thysanoptera,
Thripidae). - Proceedings of the Entomological Society of Washington
96 (1): 156-161.
Links:
Mound, LA (2005): Thysanoptera (Thrips) of the World
- A Checklist. http://www.ento.csiro.au/thysanoptera/worldthrips.html