Bruce A. Harrison, NC DENR Brian Byrd, WCU Rick Hickman, Brunswick Co. Jeff Brown, Brunswick Co. Jung Kim, NC DENR

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1 Bruce A. Harrison, NC DENR Brian Byrd, WCU Rick Hickman, Brunswick Co. Jeff Brown, Brunswick Co., NC DENR

2 What this is about For 44 years I have tried to find character(s) that will separate females Oc. atlanticus and Oc. tormentor with accuracy. Since starting work in NC in February 1993, I tried to accumulate a collection of these two species that were reared with associated larva and pupa skins for each specimen. In 2004, Rick Hickman and Jeff Brown found and reared over 20 specimens (with skins) of each species and sent them to me for study. The results are included here.

3 Everyone is familiar with our annual nemesis, which we should all thank for the $$ in our pockets. However, one more time note the narrow median longitudinal stripe on the scutum and the banded legs Aedes albopictus

4 Aedes albopictus Scutum Prescutellar area Scutellum (3 lobed)

5 NOTICE. Median pale longitudinal stripe has very straight margins.

6 Oc. dupreei Note. Median stripe is wider than that on atlanticus and tormentor, margins of pale stripe not straight, and pale scales extend back into and on both sides of prescutellar area. Robert Collins

7 Ochlerotatus dupreei Notice. First, Oc. dupreei is a tiny species. Second, the pale head scales are different, i.e., those on dupreei are broad, while those on atlanticus and tormentor are long and narrow. Oc. dupreei Oc. atlanticus

8 M. Cutwa-Francis, FMEL Oc. infirmatus

9 Ochlerotatus infirmatus NOTE. Scales can be white, not yellow, and white area ends before prescutellar area

10 A partially rubbed Oc. infirmatus Note. Pale scutum scales do not extend back into or beside the prescutellar area Pale scales on midline

11 Separating rubbed Oc. atlanticus and Oc. tormentor from Oc. infirmatus using Subspiracular Scales -Oc. atlanticus and Oc. tormentor without SSc scales. spiracle Oc. atlanticus Oc. infirmatus -Oc. infirmatus with SSc scales No scales Scales

12 This is what we used to call Ochlerotatus atlanticus/tormentor NOTE. The median pale stripe is on head, scutum, and scutellum. But, the tarsi do not have pale bands. Alice Anderson

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14 MALE GENITALIA CHARACTERS Oc. tormentor Oc. atlanticus

15 LARVAL DIFFERENCES Oc. atlanticus Oc. tormentor Carpenter & LaCasse 1955 Carpenter & LaCasse 1955

16 Robert Collins Oc. fulvus pallens Oc. atlanticus Oc. tormentor Oc. infirmatus Sketches adapted from Bickley and Harrison (Mosquito Systematics, Vol 21 (3) 1989)

17 Oc. tormentor Parker Whitt

18 1. Head scale arrangement on top of the head 2. Width of median longitudinal white stripe on scutum just before the prescutellar area* * Originally published by Roberts and Scanlon (1979, Mosquito Systematics 11: )

19 Ochlerotatus atlanticus First Character. Dark scales behind the eyes reach the eyes on both sides. In other words, the eyes are not separated by pale scales from the dark patches on each side of the head. (99 % character)

20 Ochlerotatus atlanticus Second Character. width of median stripe on scutum remains about the same back to the prescutellar area (90-95% character)

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22 Ochlerotatus tormentor First Character. Dark scales behind eyes do not reach the eyes. In other words, white ocular scales separate the eyes and dark scale patches on the head. (99 % Character)

23 Ochlerotatus tormentor Second Character. Width of median line on scutum narrows posteriorly just before it reaches the prescutellar area. (90-95 % character, but variable) Extreme Variation Normal

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25 Testing the characters At the Natl. Museum of Nat. History (Smithsonian). Total of 201 females were available to check (none reared with associated skins and no recent material). 1. Of 47 originally labeled as Oc. tormentor, 14 were misidentified Oc. atlanticus (30 % error) 2. Of 154 originally labeled as Oc. atlanticus, 24 were misidentified Oc. tormentor (16 % error) 3. Results = no intermediates found; there were 57 Oc. tormentor from 10 states and 144 Oc. atlanticus from 12 states and D.C. Comments on misidentification rates: error rates were lower than expected, possibly due to associated males being identified at time of collection.

26 Morphological studies are continuing. 1. Characters have been tested on local and Smithsonian Museum specimens 2. Two characters will separate females of Oc. atlanticus and Oc. tormentor with a high degree of accuracy DNA PCR studies by Dr. Brian Byrd are underway.

27 rdna ITS2 PCR L N/C Lane L 100 bp Ladder 1 Oc. atlanticus (A 15) 2 Oc. atlanticus (A 9) 3 Oc. tormentor (T 18) 4 Oc. tormentor (T 9) N/C Negative Control (H 2 O) The second internal transcribed spacer (ITS2) was PCR amplified from three of four specimens Size similarities (~400bp) necessitates sequencing the amplicons. (pending)

28 What species is this male? I believe this is the only species in North America that has the entire scutum covered in white scales (small areas that look brown are rubbed).