J. Douglas Hood.
Two New Thysanoptera from the United States.
Psyche 43:1-9, 1936.

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PSYCHE
VOL. XLIII MARCH, 1936 No. 1
TWO NEW THYSANOPTERA FROM THE
UNITED STATES
University of Rochester, Rochester, N. Y. The types of the two new species described below are in the author's collection.
Taeniothrips vaccinophilus sp. nov. (Fig. 1) Female (macropterous) . - Length about 0.88 mm. (dis- tended, 1.01 mm.). Color clear pale yellow, with tip of ab- domen and sides of thorax just perceptively darker ; antennae concolorous with paler portions of body in segments I and 11, 111 similarly pale at base, lightly shaded with gray dis- tally, IV pale in basal third or fourth, more darkly shaded with gray beyond but somewhat paler in apical portion, V somewhat darker than IV, more briefly pale at base and with the short pedicel gray, VI about concolorous with darker portions of V, somewhat paler basally, VII and VIII uniform gray but paler than VI ; wings of fore pair nearly colorless in basal fourth, yellowish beyond, the anal area (scale), a narrow line along posterior margin in distal three-fourths, and a broader patch along anterior margin of second fourth, light gray; ocellar pigmentation bright red. Head about two-thirds as long as greatest postocular width, distinctly broader across eyes; cheeks smooth, nar- rowing only slightly to eyes, roundly converging to the dis- tinctly narrower base, thus not swollen; occiput with about five faint transverse lines of sculpture, of which the an- terior is the most distinct; vertex slightly elevated in the ocellar area, distinctly excavated between it and insertion of antennas; frontal costa with an exceedingly minute V- shaped notch; interocellar setae short and pale, about 13p in length and somewhat shorter than postocellars, a similar but more minute pair of setae near inner margins of eyes



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Fig. 1. Tasniothrips vaccinophilus sp. nov., 2, holotype. a, head and prothorax; b, right antenna; c, right fore wing.



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19361 New Thysanoptera from the United States 3 directly laterad of median ocellus ; postocular and genal setae minute and pale, two pairs of the former, three pairs of the latter. Eyes rather large and prominent, somewhat pro- truding, two-thirds as long as head and 0.8 as wide as their interval. Ocelli sulbequal in size, about 13p in diameter, pos- terior pair about 18p apart and lop from median ocellus, which is directed forward and overhanging. Antennae three times as long as head, rather stout, segments I11 and IV with the usual forked trichomes short, IV and V with pedicel short. Mouth-cone about attaining posterior margin of prosternum (maxillary palpi not clearly visible in the type material).
Prothorax about 1.4 times as long as head and about 1.4 times as wide as long; pronotum almost smooth, with a few faint transverse lines posteriorly, of which one between the inner pair of major setae is mfost distinct; all setse pale yel- low, the outer pair at posterior angles 50p, inner 44p, be- tween the latter and midway between the heavy transverse line of sculpture and the posterior margin only one pair of minor setse, these about 24p apart and subequal to intero- cellars and a number of other setae scattered over pronotum. Fore wings nearly 11 times as long as width just beyond scale, recurved at tip; setae pale in color, anterior vein with a sub-basal group of three arising opposite distal half of scale, followed by a second group of three in the dark por- tion of wing and by three more in distal half of wing, the last two in the series closer together; posterior vein with three nearly equidistant setae in distal half of wing; costal margin with about 16 setae.
Abdomen of normal form, about 1.24 times as wide as pterothorax, nearly free of sculpture, posterior margin of tergum VIII without comb; tergum X not divided along median line; dorsal setae on IX and X about 68p long, those on IX much stouter.
Measurements of holotype (
) : Length about 0.88 mm.
(distended, 1.01 mm. ; head, length 0.065 mm., width across eyes 0.103 mm., width across cheeks 0.099 mm., width at base 0.093 mm.; eyes, length 0.044 mm., width 0.032 mm., interval 0.040 mm. ; prothorax, median length of pronotum 0.092 mm., width 0.130 mm. ; pterothorax, width 0.164 mm. ; fore wings, length 0.423 mm., width just beyond scale 0.039



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Fig. 2. Eurythrips sculpturus sp. nov., $. a, head and pro- thorax, paratype; b, right antenna, holotype.



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19361 New Thysanoptera from the United States 5 mm., at middle 0.027 mm.; abdomen, greatest width 0.204 mm.
Antenna1 segments : 1 2 3 4 5 6 7 8
Length (p) : 20 30 34 31 27 33 8 15
Width (p) : 22 23 17 17 17 17 7 5
Total length of antenna 0.198 mm.
Described from 9 females taken by the author on a species of Blueberry (Vaccinium sp.) , at Canandaigua Lake, New York, May 27,29, and 30,1934 [Hood Nos. 567 and 5681. The assignment of this species to the heterogeneous col- lection of forms now reposing in Tzniothrips does not thor- oughly satisfy me; yet I dislike to erect a new genus for it until a thorough study has been made of its relatives. The number of segments in the maxillary palpus cannot be de- termined with certainty from my material, though I strong- ly suspect that there are but two instead of the conventional three.
It is certainly a most distinct species. The small size, pale color, minute frontal notch, short abdominal setae, and the absence of a comb from the eighth abdominal tergum are all important characters in its recognition; but the presence of only two minor setae on the posterior margin of the pro- notum, instead of the usual six or eight, is distinctive. Eurythrips sculpturus sp. nov. (Fig. 2)
Female (brachypterous) . - Length about 1.4 mm. Color of head, thorax, and legs bright yellow, all somewhat shaded with brown at sides, pterothorax darkened along anterior margin; abdomen brown, terga 111-VIII each with the sub- basal line darker and with a dark gray quadrate blotch oc- cupying the basal half of the median fourth beyond the line, the tube blackish brown and much darker than rest of ab- domen ; pigmentation in fat-body maroon red, present in the ocellar region, in sides of head at base, sparingly in pro- thorax, and abundantly along sides of pterothorax and ab- domen and in abdominal segment 11, entirely wanting in tube and all appendages; antennae about concolorous with head in segment I, I1 darker, especially at sides, I11 yellow, shaded with gray in expanded portion, especially at sides,



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6 Psyche [March
IV-VI with pedicels grayish yellow and the swollen distal portions gray-brown to blackish brown and successively darker, remainder of antennae nearly or quite blackish brown and coneolorous with tube, the pedicel of VTT some- what paler.
Head about 1.36 times as long as greatest width, which is at middle of cheeks; the latter decidedly rounded to near eyes, sharply constricted just behind eyea, and converging in basal third, with a somewhat wider and distinct basal collar ; at thig level the head is only slightly broader than at the postocular constriction; width across eyes about 0.9 the greatest width across cheeks; the latter roughened as seen from above because of rather heavy lines of reticulation which form distinct polygons over the whole surface of head, and with six pairs of pale, curved, expanded see about 18p in length; postocular setsa expanded and curved at tip, 27p long; a slenderer but otherwise similar pair of occipital setae, 27p long and 5% apart, situated about mid- way between postoculars and base of head ; vertex and occi- put elevated, the former somewhat excavated in front for the reception of the forwardly-directed median ocellus, with a pair of strong postocellar setse which are similar to occipitals, and a slender pointed pair directly between the vertical pores and the median ocellus. Eyes rounded, strongly protruding, coarsely facetted, only 0.22 as long as head, their length distinctly greater than their width, which is approximately half their interval- Ocelli subequal, pos- terior pair much farther apart than their distance from an- terior ocellus, their diameter (15~) about half their inter- val; median ocellus with its posterior margin in the same transverse line as anterior margin of eyes. Antennas a-bout
twice as long as head, the four baaal segment8 marked with weak lines of reticulation which are most distinct on 11; Ill-VII subclaviform, the pedicels of about equal width but successively shorter on IV-VII, VIII narrowed at base ; sense- cones long and slender, disposed on inner (and outer) surfaces of segments as follows: III 1 (I), IV 1 (I), V 1 (I+), VI 1 (1+l) ; setae long and slender, the major dorsal ones on 11-VI knobbed. Mouth-cone short and broadly rounded, about attaining middle of prosternum. Prothorax along median line of pronoturn about two-



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19361 New Thysanoptera from the United States 7 thirds as long as head, and (inclusive of cox@ about 1.8 times as wide as long, with a short vestigial internal median thickening and a nearly straight thickening across posterior fourth, between posterior marginal setae, this line bearing a pair of minute setae (30p apart) at middle; most of dorsal surface faintly subreticulate; epimeron not or only slightly fused with pronotum ; anterior marginal setae very minute, the others long, dilated and obliquely truncate at tip, the epimeral 4 6 ~ and longest, the others 32-34p, coxals dilated apically 'but minute (13~). Pterothorax slightly wider than prothorax; mesonotum with faint anastomosing lines over whole surface, these generally forming transversely elon- gate areas ; metanotum polygonally subreticulate. Legs normal, fore tarsi with a small slender tooth; all femora and tibiae distinctly reticulate and thus roughened in appearance. Wings short and pad-like, not attaining base of abdomen, fore pair with a single seta comparable in size and structure with posterior marginals.
Adornen large and heavy, about 1.6 times as wide as pro- thorax across coxae, polygonally subreticulate in terga I-IX, except median portion of the last, distal portion of 11-IX, and basal to the dark line across 111-VIII; reticulation of I somewhat coarser than that of metanotum or of the other terga, the lines at sides of I1 and across middle of other terga minutely asperate ; all major setae at sides of segments I-VIII similar in form to postoculars and prothoracics, i.e., moder- ately stout, expanded and obliquely truncate apically, this giving them a somewhat golf-club-like form when seen from the proper direction, the lateral set2 on VII 60p, on IX 107p, dorsals on IX (76~) scarcely hooked, terminal set= pointed, 77~.
Measurements (mostly of paratype,* ? ) : Length about 1.3 mm. (fully distended, 1.4 mm.) ; head, length 0.213 mm., width across eyes 0.140 mm., width at posterior margin of eyes 0.125 mm., width at middle of cheeks 0.157 mm., width near base 0.130 mm.; eyes, length 0.047 mm., width 0.037 mm., interval 0.070 mm.; ocelli, diameter 0.015 mm., inter- *In order that the coloration of the holotype might be preserved, it was deemed better to macerate the topotypic paratype in NaOH and to measure it. Accurate measurements are possible only in specimens so treated and then mounted to float free in balsam, without cover- glass pressure.




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8 Psyche [March.
val between posterior ocelli 0.030 mm., distance between an- terior and posterior 0.018 mm. ; prothorax, median length of pronotum 0.142 mm., width (inclusive of coxse) 0.253 mm. ; pterothorax, greatest width 0.266 mm.; abdomen, greatest width (at segment 111) 0.415 mm.; tube, length 0.165 mm. (in holotype 0.139 mm.), width at base 0.071 mm. (holo- type, 0.063 mm.) , at apex 0.027 mm. (holotype, 0.027 mm.) . Antenna1 segments : 1 2 3 4 5 6 7 8
Length (u,) : 43 55 67 63 70 55 40 41
Width (p) : 41 34 31 29 27 24 20 13
Total length of antenna 0.434 mm.
MalZe (brachypterous) . - Length about 1.0 mm. (par- tially distended 1.11 mm.). Color and structure essen- tially as in female, but with the abdomen, particularly seg- ment IX, paler, this being nearly yellow and darkened at sides with brown; transverse chitinous line near posterior fourth of pronotum heavier and darker, elevated, somewhat overhanging posteriorly, weaker between the two setae at middle; lateral seta on segment IX of abdomen short (32~). Measurements of allotype ( s ) : Length 1.0 mm. ; head, length 0.151 mm., width across eyes 0.110 mm., width at posterior margin of eyes 0.099 mm., width at middle of cheeks 0.125 mm., width near base 0.114 mm.; eyes, length 0.033 mm., width 0.024 mm., interval 0.062 mm. ; postocular setae, length 0.027 mmi. ; prothorax, median length of prono- turn 0.090 mm., width (inclusive of coxse) 0.200 mm.; an- terior lateral setse, length 0.020 mm., midlaterals 0.033 mm., epimerals 0.036 mm., posterior marginals 0.034 mm. ; ptero- thorax, greatest width 0.196 mm.; abdomen, greatest width (at segment 111) 0.249 mm. ; tube, length 0.099 mm., width at base 0.049 mm., at apex 0.023 mm.
Antenna1 segments : 1 2 3 4 5 6 7 8
Length (p) :
37 43 52 48 53 43 32 34
Width (p) :
33 28 26 25 23 20 18 12
Total length of antenna 0.342 mm.
Described from three females and three males, taken by Dr. J. W. Folsom, at Tallulah, Louisiana, April 2 (1 9 , para- type), May 11 (1 $, holotype, and 1 $, allotype, Hood No. 566), and October 4, 1934, "in humus".
It is not difficult to distinguish this interesting little spe-



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19361 New Thysanoptera from the United States 9 cies from its congeners. The distinct dorsal reticulation, the oblique truncation of the dilated tips of the stout setae, and the transverse pronotal thickening are all peculiar to it. It bridges beautifully the gap which has previously existed between the group comprising Sagenothrips, Terthrothrips, Glyptothrips (and possibly one or two other genera) and that portion of the Trichothrips group which culminates in Malacothrips land Eurythrips. On the basis of the defini- tion alone of Sagenothrips it would seem more properly as- signable to that genus; but I find little excepting sculpture to exclude it from the older genus Eurythrips. Further- more, in the series of Eurythrips before me, a complete transition is observable in sculpture from those species which are nearly glabrous above to such species as the pres- ent one, in which the dorsal anastomosing lines take on a polygonal disposition and become pronouncedly elevated. Differences in sculpture which are of degree rather than of kind are seemingly never of generic, and certainly never of tribal, value in the Thysanoptera. Our classificatory scheme of the group contains many super-generic terms which have been proposed as the result of an eager and pre- mature search for differences, untempered by an equal assi- duity in a search for similarities.




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