. Bulletin. Natural history; Natural history. 358 Illinois Natlrai, HlsToK^â St rvl^' Bri lftin V.,1. L'9, Art. -i Head wider than long to as long as wide. Cheeks barely bulged to con- siderably bulged. Antennae eight seg- mented, abnormally seven segmented in North America but occasionally normally seven segmented elsewhere. Antennal segments III and IV with forked sense cones. Maxillary palps usually three segmented, labial palps two segmented. Prothorax with only the two pairs of epimeral setae well developed. Meso- spinasternum separated from meta- sternum by a suture. Fore legs not en- la
. Bulletin. Natural history; Natural history. 358 Illinois Natlrai, HlsToK^â St rvl^' Bri lftin V.,1. L'9, Art. -i Head wider than long to as long as wide. Cheeks barely bulged to con- siderably bulged. Antennae eight seg- mented, abnormally seven segmented in North America but occasionally normally seven segmented elsewhere. Antennal segments III and IV with forked sense cones. Maxillary palps usually three segmented, labial palps two segmented. Prothorax with only the two pairs of epimeral setae well developed. Meso- spinasternum separated from meta- sternum by a suture. Fore legs not en- larged. All tarsi two segmented. Fore wings with two veins, setae on fore vein often interrupted, setae on hind vein uniformly spaced, fringe cilia wavy. Abdomen with pleural plates. Ter- gites and sternites without microsetae. Median pair of setae placed far apart on the intermediate abdominal ter- gites. Abdominal sternites with or without accessory setae in addition to the posterior ones. Abdominal tergite VIII with or without posterior comb. Males with or without sternal glan- dular areas. The type of the genus, a European species, has an elongated head and greatly bulged cheeks, and lacks ac- cessory abdominal sternal setae. Spe- cies of Taeniothrips which most closely resemble the type-genus in the char- acteristic of the head occur indigenous- ly in western North America rather than in the East. In none of our native Illinois species is the head particularly bulged. Crawford (19416) and Speyer (1951), by introducing the character- istic of the abdominal sternal setae in the definition of the species, helped the taxonomy of the genus over an enormous hurdle. Their discovery that some species have accessory setae on the abdominal sternites whereas others do not permits the easy separation or regrouping of many hard-to-identify species. Mr. Speyer has pointed out to me that this characteristic should be further investigated and analyzed in certain species in the genus Thrips
Size: 821px × 3043px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., booka, bookcentury1900, bookdecade1910, booksubjectnaturalhistory
