Corresponding author: Charles R. Bartlett (
Academic editor: Michael Wilson
The number of species of planthoppers (excluding Delphacidae) known from Delaware is updated from 7 (in 4 families) to 62 species (in 9 families). Specimen abundance is tallied by county and seasonally by two week intervals. The Chao1 abundance estimator suggests that the true fauna may be 74 species, although species incidence tallied from adjacent states (MD, NJ, PA and DC) suggests that a total fauna of approximately 100 species may be possible. An artificial key is presented to genus and select species with photos of most included taxa.
The distribution of planthoppers (
Our objectives were to provide an abundance-based list of planthopper species found in Delaware (excluding
Planthopper specimens from Delaware, Maryland, New Jersey, and Pennsylvania in the UDCC were identified to species. Identification of some taxa requires dissection of male genitalia, in which case the abdomen was removed (sometimes after relaxing the specimen overnight in high humidity) and cleared for 24 hours in 15% potassium hydroxide (KOH), rinsed in water and transferred to glycerol for observation and manipulation (see, e.g.,
Family-level nomenclature follows
Incidence records were listed for Maryland, New Jersey, Pennsylvania, and the District of Columbia based on literature (see below) and specimen records. Specimen records were compiled both from the UDCC and USNM collections. Specimens from Delaware were totaled by county and collection date increment. For collection date tallies, each month was divided into two increments, “early” (the 1–15th of each month), and “late” (the 16th-end of month) dates. Specimens with incomplete date information were omitted from these counts (resulting in the number of specimens tallied for seasonal data for some species to be less than the number of specimens observed). Because some species were at times found in abundance, seasonality records were tallied in two ways; complete specimen counts, and observation records where each series (all specimens recorded from a particular location and date) was tallied as a single observation.
To help assess completeness of the inventory, literature records were compiled from published sources (viz.
Photographs were taken using a Nikon SMZ-1500 Digital Imaging Workstation with Nikon DS-U1 digital Camera and NIS Elements Imaging software (version 3.0). Line drawings were made by Kimberley Shropshire (see acknowledgements) by tracing photographs and rendering detail freehand with reference to specimens.
Total planthopper species richness for Delaware was also evaluated using Chao’s (1984) abundance based estimator of species richness calculated as
Among 1,734 specimens from Delaware we observed 62 planthopper species in 27 genera and 9 families (
County and seasonality records for Delaware planthoppers. Number of observed specimens given for county records, with distribution of records over the year provided, including earliest and latest observation. For seasonality records, records were divided into early (day 1–15 of the month) and late (remainder of month) observations, and for each observation a specimen count is followed parenthetically by number of independent collecting events (see methods). Sum of seasonality records may be less that sum of specimen records as ambiguous date records were omitted from seasonality tally. Column totals below seasonal entry is a count of the number of species observed during that time interval.
County records | March | April | May | June | July | August | September | October | ||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
New Castle | Kent | Sussex | Sum | Early date | Late date | Early | Late | Early | Late | Early | Late | Early | Late | Early | Late | Early | Late | Early | Late | Early | Late | |
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29 | 5 | 11 | 45 | 16-May | 5-Oct | 1(1) | 5(1) | 8(4) | 6(5) | 11(6) | 9(7) | 4(3) | 1(1) | ||||||||
|
138 | 10 | 2 | 150 | 2-Jul | 7-Oct | 16(7) | 25(17) | 14(10) | 24(15) | 49(18) | 22(8) | 22(7) | 2(2) | ||||||||
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9 | 15 | 24 | 29-Jul | 7-Oct | 1(1) | 4(1) | 6(3) | 10(1) | 1(1) | 1(1) | |||||||||||
|
1 | 1 | 26-Jul | 1(1) | ||||||||||||||||||
|
10 | 10 | 3-Aug | 27-Sep | 1(1) | 8(1) | ||||||||||||||||
|
1 | 1 | 7-Oct | 1(1) | ||||||||||||||||||
|
3 | 3 | 4-Aug | 8-Sep | 1(1) | 2(1) | ||||||||||||||||
|
4 | 4 | 28-Jul | 7-Oct | 1(1) | 3(1) | ||||||||||||||||
|
1 | 1 | 28-Aug | 1(1) | ||||||||||||||||||
|
1 | 1 | 7-Oct | 1(1) | ||||||||||||||||||
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15 | 141 | 9 | 165 | 30-May | 3-Oct | 8(1) | 9(1) | 4(1) | 69(1) | 70(1) | 1(1) | ||||||||||
7 | 7 | 29-Jun | 21-Aug | 2(1) | 3(2) | 2(1) | ||||||||||||||||
|
53 | 1 | 54 | 22-Jun | 9-Oct | 4(1) | 6(4) | 3(2) | 15(3) | 12(5) | 12(6) | |||||||||||
|
2 | 2 | 29-Jun | 2(1) | ||||||||||||||||||
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|
9 | 3 | 34 | 46 | 22-Jun | 4-Aug | 1(1) | 4(2) | 20(5) | 17(8) | 2(1) | |||||||||||
|
2 | 2 | 29-Jun | 3-Jul | 1(1) | 1(1) | ||||||||||||||||
|
3 | 3 | 29-Jun | 1(1) | ||||||||||||||||||
1 | 1 | 15-Jul | 1(1) | |||||||||||||||||||
|
1 | 1 | 9-May | 1(1) | ||||||||||||||||||
|
45 | 45 | 8-May | 29-Jul | 10(4) | 1(1) | 5(3) | 28(6) | 1(1) | |||||||||||||
2 | 2 | 24-Apr | 2-Jun | 1(1) | 1(1) | |||||||||||||||||
|
1 | 3 | 4 | 7-Jun | 29-Jul | 3(1) | 1(1) | |||||||||||||||
|
57 | 3 | 60 | 18-Jun | 29-Jul | 27(3) | 30(3) | 3(3) | ||||||||||||||
|
3 | 1 | 4 | 11-Jun | 29-Jun | 3(2) | 1(1) | |||||||||||||||
1 | 1 | 22-Jul | 1(1) | |||||||||||||||||||
|
1 | 1 | 12-Jul | 1(1) | ||||||||||||||||||
|
90 | 90 | 16-Jun | 14-Jul | 66(4) | 24(1) | ||||||||||||||||
|
1 | 1 | 19-Jun | 1(1) | ||||||||||||||||||
|
265 | 2 | 47 | 314 | 22-Apr | 30-Aug | 2(1) | 10(3) | 21(2) | 38(10) | 198(18) | 35(12) | 1(1) | 3(3) | ||||||||
|
10 | 1 | 11 | 24-Jun | 16-Jul | 1(1) | 9(5) | 1(1) | ||||||||||||||
|
1 | 1 | 27-Jun | 1(1) | ||||||||||||||||||
|
6 | 6 | 16-Jun | 27-Jun | 6(3) | |||||||||||||||||
59 | 4 | 63 | 23-May | 26-Jul | 1(1) | 47(6) | 12(8) | 3(3) | ||||||||||||||
4 | 1 | 5 | 29-Jun | 26-Jul | 2(2) | 3(3) | ||||||||||||||||
|
2 | 2 | 11-Aug | 2(1) | ||||||||||||||||||
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27 | 20 | 47 | 23-May | 4(2) | 3(2) | 19(8) | 16(5) | 5(2) | |||||||||||||
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5 | 5 | 22-Jul | 9-Sep | 1(1) | 1(1) | 1(1) | 2(1) | ||||||||||||||
|
5 | 3 | 1 | 9 | 19-Jun | 19-Oct | 1(1) | 3(3) | 2(2) | 3(1) | ||||||||||||
|
7 | 7 | 18-Jun | 1-Sep | 3(2) | 3(2) | 1(1) | |||||||||||||||
|
19 | 10 | 29 | 1-Mar | 21-Oct | 9(3) | 7(3) | 3(3) | 2(2) | 1(1) | 3(2) | 3(1) | 1(1) | |||||||||
|
1 | 1 | 13-Aug | 1(1) | ||||||||||||||||||
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10 | 1 | 11 | 26-Jul | 13-Aug | 6(1) | 5(3) | |||||||||||||||
|
21 | 2 | 23 | 7-Jul | 30-Aug | 1(1) | 19(1) | 1(1) | 2(1) | |||||||||||||
|
6 | 8 | 14 | 9-Jun | 8-Sep | 5(1) | 5(1) | 2(1) | 1(1) | |||||||||||||
|
1 | 1 | 23-Jun | 1(1) | ||||||||||||||||||
|
1 | 1 | 3-Aug | 1(1) | ||||||||||||||||||
16 | 16 | 9-Jun | 26-Jul | 1(1) | 3(1) | 12(1) | ||||||||||||||||
|
3 | 3 | 2-Sep | 6-Sep | 3(2) | |||||||||||||||||
11 | 2 | 23 | 36 | 14-Jun | 7-Oct | 1(1) | 2(1) | 1(1) | 1(1) | 17(6) | 4(3) | 7(1) | ||||||||||
|
1 | 1 | 2 | (22-26)-June | 12-Jul | 1(1) | 1(1) | |||||||||||||||
|
1 | 1 | 15-Jul | 1(1) | ||||||||||||||||||
|
2 | 2 | 26-Jul | 9-Aug | 1(1) | 1(1) | ||||||||||||||||
|
7 | 5 | 12 | (19-20)-July | 7-Sep | 2(2) | 4(3) | 6(2) | ||||||||||||||
|
2 | 2 | 4 | 3-Jul | 4-Aug | 1(1) | 2(1) | 1(1) | ||||||||||||||
|
1 | 1 | 1-Jul | 1(1) | ||||||||||||||||||
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14 | 14 | 21-Aug | 1-Sep | 10(2) | 4(1) | ||||||||||||||||
|
16 | 1 | 1 | 18 | 27-Jul | 13-Sep | 3(2) | 4(3) | 11(7) | |||||||||||||
|
8 | 8 | 18-Jul | 20-Jul | 2(2) | |||||||||||||||||
|
7 | 7 | 19-Aug | 21-Aug | 7(2) | |||||||||||||||||
|
1 | 1 | 17-Jul | 1(1) | ||||||||||||||||||
|
92 | 2 | 94 | 11-Jul | 1-Oct | 1(1) | 50(14) | 4(4) | 12(4) | 3(1) | 11(4) | 10(1) | ||||||||||
|
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85 | 18 | 9 | 112 | 2-Jul | 21-Oct | 2(1) | 14(12) | 16(11) | 23(18) | 19(12) | 15(12) | 8(5) | 11(3) | ||||||||
|
58 | 12 | 13 | 83 | 22-Jun | 11-Oct | 2(2) | 6(6) | 15(11) | 20(14) | 12(7) | 14(10) | 5(5) | 4(3) | ||||||||
|
18 | 2 | 1 | 21 | 22-Jul | 1-Oct | 2(2) | 2(2) | 8(3) | 5(3) | 2(1) | |||||||||||
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4 | 4 | 4-Jun | 18-Jul | 2(2) | 1(1) | 1(1) | |||||||||||||||
|
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1 | 1 | 2 | 2-Aug | 17-Oct | 1(1) | 1(1) | |||||||||||||||
|
14 | 14 | 4-Jul | 16-Sep | 2(2) | 1(1) | 1(1) | 2(2) | 7(5) | 1(1) | ||||||||||||
Totals | 1253 | 209 | 272 | 1734 | 1 | 0 | 0 | 3 | 2 | 6 | 9 | 24 | 28 | 36 | 27 | 19 | 17 | 13 | 14 | 5 |
The most abundant species were
Rank abundance frequency distribution of planthopper species of Delaware. Number of specimens of each species found in Table 1.
The Chao1 biodiversity estimator was calculated as 74.08 species, indicating that 12 additional planthopper species are predicted to occur. The incidence list for Delaware and adjacent states (
Planthopper incidence list for Delaware, Maryland New Jersey, Pennsylvania, and the District of Columbia. Specimen records are indicated by “S”, literature records by “L”, tentative or subsequent questioned records are annotated by “?”, and records reported as erroneous by “E”. Records from Wilson and McPherson (1980) except as noted.
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S | S,L | S,L | S,L | S,L | ||
S,L | S,L | S,L | S,L | S | ||
S | S,L | |||||
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S | S,L | S | S | |||
S,L | S,L | S,L | S,L | S | ||
S,L | S,L | S | ||||
S | S,L | S | ||||
S | S,L | |||||
S | S,L | S,L | S,L | S | ||
S | S | S,L | S | |||
S | L | L | S,L | |||
L | L | S,L | ||||
L | L | L | ||||
S | S | S,L | S | |||
S,L | S,L | S,L | ||||
S,L | L | |||||
S | L | L | S | |||
|
||||||
L | ||||||
S | ||||||
L? | ||||||
S | S,L | S,L | ||||
S,L | L | |||||
L | L | |||||
S | S,L | S,L | S,L | S | ||
S | S | S | S,L | |||
S | S | S | ||||
L | L | |||||
L | L | |||||
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|
|
Noted as error by |
||||
S,L | S,L | L |
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S | ||||||
S | ||||||
|
Noted as error by |
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S | S | |||||
L | Kramer 1981 | |||||
S | L | L | ||||
L | L | Kramer 1981(PA record) | ||||
S,L | S,L | S,L | S,L | Kramer 1981 | ||
S,L | Kramer 1981 | |||||
S,L | S,L | S | Kramer 1981 | |||
L | L | |||||
S,L | ||||||
S | S,L | S,L | ||||
S | S,L | L | S,L | S | ||
S,L | ||||||
S | S,L | S | ||||
S,L | S | |||||
S | L | |||||
S | S,L | S,L | S,L | S,L | ||
S | S,L | L | S,L | L | ||
S | S,L | S | S,L |
|
||
S | S,L | S,L | S | L |
|
|
S | S,L | S,L | S,L |
|
||
S | S,L | S,L | S,L | L | ||
|
S | S | S | |||
|
S | S | S | |||
S | L | L | Kramer 1981 | |||
S,L | S,L | S,L | S | |||
S | S,L | |||||
S,L | ||||||
S | S,L | Kramer 1981 | ||||
|
||||||
L | ||||||
L | ||||||
L | ||||||
S | S,L | |||||
S | L | L | ||||
S | S | L | S,L | S | ||
S | S,L | S,L | S,L | |||
S | S,L | S |
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S,L | S |
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S,L |
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S | L | S |
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S,L | S,L | S,L |
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S,L |
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S | S,L |
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S | S,L | S,L | S |
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S,L | S,L |
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S | L |
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S,L | S,L | S |
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S | S,L |
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S,L |
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S | S,L |
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|
S | S | S | |||
S | L | L | L | |||
L | L | L | ||||
L | L | L | ||||
S | L | L | S,L | |||
S | L | |||||
S | ||||||
S | L | L | ||||
S | L | L | ||||
S | S,L | L | S,L | |||
S | S | L | ||||
S,L | ||||||
L | ||||||
S | S | |||||
|
||||||
L | L | |||||
L | L | S,L | L | |||
L | L | L | ||||
S,L | ||||||
S | S | S,L | ||||
S | S | L | S | |||
S | S,L | S,L | L | |||
L? | Record probably in error. | |||||
S | L | S,L | S | L | ||
S | L | S,L | L | L | ||
S | S,L | S,L | S,L | L | ||
|
||||||
S | S,L | S,L | S,L | L | ||
L | Species needs confirmation. | |||||
S,L | S,L | S,L | S,L | L | ||
S | S | S | S | S | ||
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S | L | |||||
S | ||||||
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L | Originally reported by |
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S | S | S,L | S,L | S,L | ||
S | L | L | ||||
S | S,L | S,L | S | L | ||
New records* | 55 | 22 | 5 | 8 | 21 | |
Total species* | 62 | 88 | 74 | 60 | 46 |
*Unidentified females and errors excluded,
The seasonality data suggests that the optimal time of year to find planthoppers in Delaware is between late June and early August (
Specimens reported incidentally by
Planthoppers reported by
Plant Family | Plant species | Planthopper species | |||
---|---|---|---|---|---|
|
|
||||
Native | |||||
|
|
0 | 0 | 0 | |
|
|
0 | 2 | 0 | |
|
|
2 | 0 | 0 | |
|
|
0 | 0 | 0 | |
|
|
0 | 0 | 0 | |
|
|
0 | 0 | 0 | |
|
|
4 | 0 | 0 | |
|
|
6 | 0 | 0 | |
|
|
0 | 2 | 0 | |
|
|
7 | 0 | 0 | |
|
|
2 | 0 | 0 | |
|
|
1 | 1 | 1 | |
|
|
1 | 0 | 0 | |
|
|
0 | 0 | 0 | |
|
|
8 | 0 | 0 | |
Subtotal | 31 | 5 | 1 | ||
Non-native congeneric plants | |||||
|
|
0 | 2 | 0 | |
|
|
3 | 0 | 0 | |
|
|
0 | 0 | 0 | |
|
|
2 | 0 | 0 | |
|
|
3 | 0 | 0 | |
|
|
2 | 0 | 0 | |
|
|
2 | 0 | 0 | |
|
|
0 | 0 | 0 | |
|
|
1 | 1 | 0 | |
|
|
42 | 0 | 0 | |
|
|
7 | 1 | 0 | |
|
|
0 | 0 | 0 | |
|
|
2 | 0 | 0 | |
|
|
2 | 5 | 0 | |
|
|
14 | 2 | 0 | |
Subtotal | 80 | 11 | 0 | ||
Alien plants | |||||
|
|
9 | 0 | 0 | |
|
|
5 | 1 | 0 | |
|
|
16 | 2 | 0 | |
|
|
9 | 1 | 0 | |
|
|
10 | 0 | 0 | |
|
|
1 | 0 | 0 | |
|
|
6 | 0 | 0 | |
|
|
1 | 0 | 0 | |
|
|
5 | 0 | 0 | |
|
|
6 | 1 | 0 | |
|
|
1 | 0 | 0 | |
|
|
0 | 0 | 0 | |
|
|
1 | 0 | 0 | |
|
|
4 | 0 | 0 | |
|
|
1 | 0 | 1 | |
Subtotal | 75 | 5 | 1 | ||
Total | 186 | 21 | 2 |
Artificial key to genus and select planthopper species from Delaware and vicinity.
1 | Hind tibiae with large movable spur at apex ( |
|
– | Hind tibiae without movable spur at apex (e.g., |
2 |
2 | Second tarsomere of hind legs with row of apical spines ( |
3 |
– | Second tarsomere of hind legs with one apical spine on each side ( |
7 |
3 | Larger species, greater than 10 mm, with patterned forewings ( |
|
– | Mostly smaller species, forewings variable; hindwings without cross veins near apex or in anal area | 4 |
4 | Forewings overlapping posteriorly ( |
|
– | Forewings not overlapping posteriorly; body variable | 5 |
5 | Beak with apical segment subequal in length and width (except |
|
– | Beak with apical segment longer than wide; forewings without tubercles on claval veins (or with tubercles on all veins); antennae never bearing projections or subtended by a shelf-like structure; median carina of frons present; parameres of male shorter than length of pygofer | 6 |
6 | Frons with two or three median carinae and/or head with elongate anterior projection ( |
|
– | Frons with one median carina; head not elongate; median ocellus usually present above frontoclypeal suture ( |
|
7 | Forewings with tubercles on claval veins (e.g., |
|
– | Forewings without tubercles on claval veins (or with tubercles on all veins); beak with apical segment longer than wide; frons not compressed, median carina generally present (e.g., |
8 |
8 | Forewings waxy, bearing tubercles between veins on clavus ( |
|
– | Forewings not waxy, without tubercles on clavus; without numerous costal crossveins (e.g., |
9 |
9 | Hind tibiae without lateral spines ( |
|
– | Hind tibiae with lateral spines ( |
10 |
10 | Usually brachypterous with forewings shorter than abdomen ( |
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– | Forewings covering abdomen (both brachypters and macropters) ( |
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11 | Body green (rarely pink) with conspicuous brownish to reddish marking along lateral portions of thoracic nota ( |
|
– | Body uniformly green (rarely pink) ( |
12 |
12 | Head distinctly produced conically ( |
|
– | Head not produced conically ( |
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||
13 | Head, including eyes, less than 2/3 as wide as pronotum ( |
|
– | Head including eyes at least 2/3 as wide as pronotum ( |
18 |
14 | Clypeus and upper half of frons dark brown or black, strongly contrasting with pale lower half of frons ( |
|
– | Frons more uniformly colored, upper half not strongly contrasting ( |
15 |
15 | Vertex short, projecting in front of eye for distance less than length of eye ( |
|
– | Vertex elongate, projecting in front of eye for distance equal to or greater to length of eye; frons more uniformly colored ( |
16 |
16 | Frons and clypeus uniformly colored ( |
|
– | Clypeus distinctly darker than frons ( |
17 |
17 | Vertex projected in front of eye for distance greater than eye length, vertex 1.3–1.5× as long as basal width ( |
|
– | Vertex projected in front of eye for distance about equal to eye length, vertex length about equal (1–0.95x) to basal width ( |
|
18 | Subcostal cell of forewing longer than 1/3 length of forewing, narrow throughout ( |
|
– | Subcostal cell of forewing about 1/3 length of forewing, wider before its apex ( |
|
19 | Frons entirely pale ( |
|
– | Frons with dark transverse bands or all dark ( |
20 |
20 | Frons with dark bands ( |
|
– | Frons uniformly dark, contrasting with pale clypeus ( |
|
21 | Upper dark band of frons mottled, distinctly paler than lower band ( |
|
– | Frons, if banded ( |
22 |
22 | Frons with two very dark transverse bands ( |
23 |
– | Frons pale with pale bands, or uniformly pale ( |
24 |
23 | Lower dark band distinctly paler near frontoclypeal suture giving frons a tricolored appearance ( |
|
– | Lower dark band uniformly dark ( |
|
24 | Pale transverse marking at frontoclypeal suture not reaching lateral margin of frons ( |
25 |
– | Frons uniformly colored or pale transverse marking at frontoclypeal suture extending to lateral margin of frons ( |
|
25 | Pale transverse marking at level of ocelli complete, reaching lateral margin of frons ( |
|
– | Pale transverse marking at level of ocelli incomplete, not reaching lateral margin of frons ( |
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26 | Head produced into weevil-like snout ( |
30 |
– | Head not produced ( |
|
27 | Vertex very broad, width at least 5–6× median length ( |
28 |
– | Vertex longer, width 2–3× median length, frons not as exposed from above ( |
29 |
28 | Head and thorax orange-tan, rest of dorsum blackish brown ( |
|
– | Uniformly pale ochreous (females) to pink (most males) in color ( |
|
29 | When viewed from the side, fastigium of head produced forward, frons slanted; vertex somewhat triangular ( |
|
– | When viewed from the side, fastigium not produced, frons not slanted; vertex broadly rounded anteriorly ( |
|
30 | Middle and front tibiae expanded |
|
– | Middle and front tibiae not expanded | |
31 | Dorsal light stripe broad and conspicuous, extending from near apex of face to apex of forewings or beyond | |
– | Dorsal light stripe not broad and conspicuous, generally of lesser extent | 32 |
32 | Nasal process distinctly pronounced, head concave ventrally in lateral view ( |
|
– | Nasal process less pronounced, head weakly convex ventrally; in dorsal view extending anteriorly beyond eye for a distance less than length of eye ( |
33 |
33 | Reddish-brown in color with a dark spot on clypeus |
|
– | Uniformly black, usually with light stripe on vertex (sometimes reaching thorax) | 34 |
34 | Legs pale ( |
|
– | Legs dark ( |
|
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35 | Antennae arising from elongated cup-like cavities anterior to eyes ( |
|
– | Antennae not within cup-like cavities, arising below eyes ( |
36 |
36 | Hind tibiae without spines (similar to |
37 |
– | Hind tibiae with one or more spines along axis before apex (similar to |
38 |
37 | Mesonotum with 5 carinae; crown strongly narrowed ( |
|
– | Mesonotum with 3 carinae; crown slightly narrowed ( |
|
38 | Mesonotum with 5 longitudinal carinae (although intermediate pair sometimes obsolete); posterior margin of crown angularly incised ( |
39 |
– | Mesonotum with 3 carinae; posterior margin of crown quadrately or roundly incised ( |
40 |
39 | Apex of basitarsus of hind leg with 12 teeth |
|
– | Apex of basitarsus of hind leg with no more than 10 teeth |
|
40 | Forewings roof-like in position with distal portions clearly separated ( |
|
– | Forewings vertical in position with distal portions oppressed ( |
|
|
||
41 | Clavus open ( |
42 |
– | Clavus closed ( |
57 |
42 | Antennae with 2 or 3 conspicuous appendages ( |
43 |
– | Antennae lacking appendages ( |
51 |
43 | General color uniformly rose or reddish ( |
|
– | General color white or yellow (e.g., |
44 |
44 | In lateral view, demarcation between vertex and frons obtusely angular ( |
|
– | In lateral view, demarcation between vertex and frons smoothly rounded ( |
|
45 | Head in lateral view 1.5× as long as broad ( |
|
– | Head in lateral view 2.0× as long as broad ( |
|
46 | Wings with conspicuous round dusky spots in cells ( |
47 |
– | Wings without conspicuous round dusky spots in cells ( |
50 |
47 | Apical margin of forewings with a row of spots in the cells ( |
48 |
– | Spots not in row within apical cells ( |
49 |
48 | Apex of head with a black line laterally followed by a broader red line ( |
|
– | Apex of head without a black line laterally ( |
|
49 | Forewings with a large black spot on the sutural margin (in the clavus) and four smaller ones in a square, including 1 in costal cell |
|
– | Forewings with spots arranged differently from above ( |
|
50 | Color of the wings dark, without distinct band ( |
|
– | Color of the wings pale with distinct reddish forked band ( |
|
51 | In lateral view, head projecting in front of eyes for a distance of less than half width of eyes; forewings with scattered spots |
|
– | In lateral view, head projecting in front of eyes for a distance subequal to width of eyes ( |
|
52 | Costa narrow; forewings with veins not crowded together to give appearance of a stigma ( |
53 |
– | Costa broader; Sc and R vein tips crowded together to give appearance of a stigma ( |
|
53 | First 3 segments of abdomen with middorsal black stripe |
|
– | Abdomen without middorsal black stripe | 54 |
54 | Forewings mostly pale with a few fuscous marked crossveins ( |
|
– | Forewings more extensively marked; most veins with smoky borders ( |
55 |
55 | Head with a single marking, below antennae; apical border of forewings with four dark round spots in the cells ( |
|
– | Head with dark or red markings above and below antennae; apical border of forewings usually without round spots in the cells | 56 |
56 | At least some veins dark in color ( |
|
– | All veins pale ( |
|
57 | Antennae terete, subtended by flattened subantennal process from gena or anterior portion of lateral margin of pronotum ( |
58 |
– | Second segment of antennae flattened (more evident in males than females), antennae not subtended by process; lateral margin of pronotum not strongly modified; face strongly compressed, frons keel-like (similar to |
|
58 | Subantennal process large, extending from gena, completely subtending antennae as a shelf ( |
|
– | Subantennal process extending from pronotum, smaller ( |
59 |
59 | Media with more than two branches, connected to cubitus by crossvein; size less than 6 mm, usually distinctly orangish ( |
|
– | Media and cubitus each with two branches, not connected by crossveins; size over 7 mm; color orangish white ( |
|
|
||
60 | Head projected in front of eyes ( |
63 |
– | Head not projected in front of eyes ( |
|
61 | Eight or fewer longitudinal veins on the forewing; color either uniformly black to dark brown in dorsal view or yellowish body with reddish-brown forewings with prominent yellow wing veins ( |
|
– | With more than 8 longitudinal veins; color not as above; carinae of frons distinct ( |
62 |
62 | Veins concolorous with forewings; body black to light reddish brown ( |
|
– | Veins of forewings dark mottled with pale; body light grey-brown ( |
|
63 | Forewings clear, macropterous; head projection anterior to eyes subequal in width to vertex; body green ( |
|
– | Forewings patterned, usually brachypterous; head projection anterior to eyes narrower than vertex; body brownish ( |
|
64 | Head projection long ( |
|
– | Head projection short ( |
|
65 | Costal cell of forewing with costal vein and membrane white ( |
|
– | Costal cell of forewing with costal vein variegated ( |
66 |
66 | Forewings reticulate over apical half (especially brachypters), veins margined with dark ( |
|
– | Forewings not reticulate over apical half ( |
67 |
67 | Pronotum and usually vertex with dark markings ( |
|
– | Pronotum and vertex without dark markings ( |
|
|
||
68 | Wings much longer than wide, distinctly narrowing caudally to caudal apex ( |
|
– | Wings slightly longer than wide, truncate to broadly rounded caudally ( |
69 |
69 | Body grey to blackish ( |
|
– | Body green ( |
70 |
70 | Frons broader than long; forewings with two rows of marginal cells along apical and trailing margin (set off by two submarginal veins) ( |
|
– | Frons longer than broad; forewings with one row of marginal cells ( |
|
|
||
71 | Forewings and much of body nearly black ( |
|
– | Forewings and body mottled ( |
|
|
||
72 | Hind wings absent or rudimentary; smaller insects, less than 4.5 mm ( |
|
– | Hind wings present, entire, with strongly marked notches at the joints of the folds, anal area large; larger insects varying from 5.5 to 8.0 mm ( |
|
73 | Uniformly colored, lacking proximal bulla ( |
|
– | Body patterned, wings with proximal bulla ( |
74 |
74 | Vertex broader than long; distinctly concave in frontal view with lateral margins elevated ( |
|
– | Vertex longer than broad, slightly concave in frontal view, lateral margins not strongly elevated ( |
|
Hind legs of planthoppers.
Lateral habitus of
Habitus of
Habitus of
Habitus of
Habitus of
Lateral habitus of
Lateral habitus of
Heads of
Lateral view of
Frontal view of
Habitus of
Line drawings of
This survey brings the known diversity of Delaware planthoppers (excluding
In addition to the planthopper fauna reported here, a preliminary inventory of the delphacids of Delaware suggests at least 54 species in the state, although additional taxa are likely to be found before the completion of that inventory.
A number of specimens presented taxonomic difficulties. In the
Species of
The only member of
A number of taxonomic issues were found among the
The derbid genus
Species in the
Ten species of
The type specimen of
Nine species of
A single specimen of
The genus
Specimens reported as
Seasonality data were compiled from available Delaware specimens as a way to begin to understand the life history of local planthopper taxa. From the available seasonality information, it appears that all non-delphacid planthoppers have a single generation a year in Delaware, with the possible exceptions of
A large number of
While the planthoppers of the eastern United States may be characterized as relatively well known from a taxonomic perspective, their faunistics and ecology remain poorly understood. Although Delaware is near the two largest insect collections in the US (the USNM and the American Museum of Natural History, both of which employ hemipterists), it is a testament to our inchoate understanding of US planthopper faunistics that this study has increased our known Delaware fauna by over 700%. The diversity of planthopper species in Delaware is expected to be relatively modest relative to other states because it is small and physiographically rather uniform, and because planthopper diversity tends to generally increase inversely with latitude (and within North America, is greatest overall in the southwest). Here we also report totals of 88 species for Maryland, 74 for New Jersey, 60 for Pennsylvania, and 46 for the District of Columbia based on a compilation of literature records and available specimens. The only other state with a modern, relatively complete, survey of its planthopper fauna is Illinois (
We are indebted to Kimberley Shropshire (University of Delaware) for the line art and most of the photography used in this work. We are grateful to Lois O’Brien for advice, support, specimens, and many helpful comments on early versions of this text; Stuart McKamey (USNM) for the loan of specimens, photographs of types, and assistance at the USNM collection; Zoë Simmons (Hope Entomological Collections, Oxford University Museum of Natural History) for locating and photographing some of the Kirby derbid types; Dmitri Logunov (Manchester Museum, University of Manchester, UK) and Mick Webb (British Natural History Museum, London) for seeking Kirby types in their collection. We are particularly grateful for past and present students whose diligent collecting has provided much of the basis for this work, especially Lawrence Barringer, Leo Donovall, Christopher Heckscher, Ashley Kennedy, Nate Nazdrowicz, Rob Snyder, and Katie Weglarz. We also thank an anonymous reviewer for helpful comments. This project was supported by the USDA Agriculture and Food Research Initiative Competitive Grants Program Grant No. 2009-55605-05006 from the National Institute of Food and Agriculture and Hatch Project W-2185 Biological Control in Pest Management Systems of Plants. Additional support was provided by the University of Delaware Department of Entomology and Wildlife Ecology.