Journal of the American Control Association, 2O(3):224-227,2004 Copyright @ 2OO4 by the American Mosquito Control Association, Inc.

CULEX (CULED DECLARATOR, A MOSQUITO NEW TO FLORIDA

RICHARD E DARSIE. JR.I AND DONALD A. SHROYER,

ABSTRACT. One specimen of a mosquito new to Florida , declarator, was first found in 1998 in Indian River County. A 2nd specimen was collected in 2OO2. Beginning in September 2OO3, Cx. declarator adtlts were regularly encountered in routine mosquito surveillance sampling, with more than 300 specimens appearing in 45 collections. Prior to our find, the U.S. distrubution was thought to be restricted to south Texas. The full extent of this species' distribution in Florida has yet to be determined.

KEY WORDS Culex declarator, Florida

INTRODUCTION butional patterns, i.e., southern counties of Texas and Florida, for example, Anopheles albimanus Florida has more species of Culex than any other Wiedemann and Mansonia titillans (Walker); see province state or in North America, north of Mex- Darsie and Ward (1981). ico, except Texas, with 16. found Six of them are Various life stages of this species have been de- only in Florida. A recently discovered species, Ca- scribed by Bonne and Bonne-Wepster (1925), Dyar lex (Culex) declarator Dyar and Knab, is being re- 1928, Matheson (1944), Yamaguti and LaCasse ported here for the lst time from Florida. Before (1951), Lane (1953), Breland (1954), Carpenter and this find, Cx. declarator was known in the USA LaCasse (1955 as Cx. virgultus), Forattini (1965), from Cameron, Bexar, and Gonzales Counties, Tex- Bram (1967), and it was included in identification as (Fisk and LeVan 1941, Breland 1953 as Culex keys by Texas State Health Department (1944), virgultus Theobald). As far as can be determined, Breland (1953), Dodge (1963, 1966, lst instar), Dyar (1928) was the lst to report this species in Darsie and Ward (1981), Clark-Gil and Darsie the USA. Breland (1954) further elucidated its pres- (1983). The bionomics of the species was discussed ence in Texas and described the adult male and lar- by Kumm et al. (1940), Kumm and Zuniga (1942), va. According to Knight and Stone (1977), it is Arnett (1948), Galindo et al. (1951), Breland (1954 widely distributed in the Neotropical Region, south as Cx. virgulrus), Aitken (1967), and Stone (1969). to Uruguay. Older literature, such as Matheson (1944) and Carpenter and LaCasse (1955), have named this MATERIALS AND METHODS species Cx. virgultus Theobald. Stone (1956) ex- plained that Lane (1953) examined the types of this The majority of all Cx. declarator collections species, two males from Rio de Janeiro, Brazil, and were incidental to routine surveillance activities of found them to be conspecific with Cx. declarator the Indian River Mosquito Control District. Speci- and synonymized it under C.r. virgultus, the older mens were captured by 4 different attractant trap name, but when Stone examined the same type, he methods: l) CDC or American Biophysics Corp. could find only one male and it was Culex nigri- light traps baited with dry ice; 2) plastic lard-can palpus Theobald. He concluded that it was best, traps baited with dry ice; 3) exit traps (based on an under the circumstances, to consider Cx. virgultus unpublished design of R. L. Frommeq Manatee an unrecognized species and resurrect the name de- Mosquito Control District, Palmetto, FL) affixed to clarator for virgultus. Furthermore, Knight and sentinel chicken coops used for arbovirus surveil- Stone (1977) listed 7 synonyms for Cx. declarator, lance; and 4) American Biophysics Corp. counter- indicating that it must be a very variable species. flow geometry trap baited with dry ice (Kline In fact, the character used by Darsie and Ward 1999). In addition, adults were also obtained by (1981) to separate Cx. declarator from the other sweeping ground vegetation in diurnal resting hab- Nearctic Culex, pale bands on the hind tarsi, may itats typical of Cx. nigripalpus, using a mehanical not be the best character to distinguish it. A study aspirator. of 50 females from Florida found that only 68Vo A progeny rearing was also accomplished from had complete bands on the joints of the hindlegs, blooded/gravid females collected at the Florida 29Vo had patches instead of complete bands, and Medical Entomology Laboratory in a chicken-bait- 2% had no pale scales on the hindtarsi. ed lard-can trap. The field-collected females were There are other species with similar U.S. distri- isolated for oviposition in 25- X 70-mm vials con- taining 5 ml distilled water. Eggs obtained were al- 'Florida Medical Entomology Laboratory, 200 9th lowed to hatch and most larvae were reared to Street SE. Vero Beach. FL 32962. adulthood. Twenty-five whole 4th instars were pre- 'Indian River Mosquito Control District, PO Box 670, served in8OVo ethanol. Another 23latvae were iso- Vero Beach, FL 32961. lated and reared individually, saving the larval and SEPTEMBER2004 C]LEX DECt-|RAton DtscovgnBo rN FLontoA

Thble l. Timeline of Culex declarator collections in Knab), O chle rotatus taenio rhync has (Wiedemann), Indian River County, FL. ciliata (Fabiciws), Psorophora col- umbiae (Dyar and Knab), Psorophora ferox (von Cumulative number positive Humboldt), Psorophora howardii Coquillett' Ur- ^fheobald, Sites Collections Specimens anotaenia lowii and Uranotaenia sap- phirina (Osten Sacken). September 28, 1998 I I 1 November 12,2OO2 2 z 2 While adult females of Cx. declarator resemble September18-30, 2003 5 9 t6 those of Cx. nigripalprs, these species can be sep- October1-15, 2003 6 15 28 as indicated below. Culex declarator adttlt '7 arated October16-31,2OO3 28 98 females are recognized by the proboscis usually Novemberl-15,2OO3 7 36 142 with a more or less distinct, long, pale area on low- 7 327 November 16-30,2OO3 er surfacel scutum clothed with dark brown, nar- row, curved scales; thoracic pleuron with a large upper mesokatepisternal scale patch, a large upper pupal exuviae, along with the corresponding adults- mesepimeral scale patch and a small lower meso- Immatures were preserved and mounted in Canada katepisternal scale patch all of broad, white scales; balsam for study. Adults were affixed to card also the pleural integument white to yellow to tan points, and the genitalia of several males were dis- with dark spots appearing as two stripes, the lower sected and mounted on slides. one on the lower mesepimeron and adjoining mid- The initial group of specimens was collected as mesokatepisternum, and the upper one small dark follows: Indian River County: Vero Beach, Florida spots on upper mesepimeron and prealar area, on Medical Entomology Laboratory compound the anterior 0.5 of anterior mesanepisternum, entire (27.58738"N, 80.37363"W), IX-28-98, I ?, ex postpronotum; posterior surface of femora and tib- CDC miniature light trap with dry ice (J. Knight); iae pale, tarsal segments either dark-scaled or with Vero Beach, Lockwood Hammock (27.57553"N, very narrow white bands; abdominal terga dark- 80.43592"W), XI-12-02, 1 9, ex mechanical aspi- scaled dorsally or with basal, very narrow, white rator (P Morgan); Vero Beach, Indian River County bands, (Fig. 1A). By contrast, Cx. nigripalpus fe- Mosquito Control District compound (27.66565"N, males have a few scales only on the lower meso- 80.44339"W). IX-12-03. I I, IX-18-03, I 9, X- katepisternum, the pleural integument is uniformly 2043, I 9, ex exit trap; X-6-03, 6 9, X-7-O3, 5 creamy or tan without dark stripes, abdominal terga ?, X-l1-03,2 I, ex ABC trap (D. Shroyer); Wa- rarely have narrow, basal, pale bands (Fig. 1B) and basso. Vickers Grove (27.78354"N, 80.44816'W), hindtarsi are dark-scaled. rx-18-03. | 9. rx-22-O3. I 9, IX-30-03, 4 9, 1 The male genitalia of Cx. declarator have been d, X-20-03, 1 9, ex exit trap (P Baffino); Wabasso, studied. The appendicula of the subapical lobe of Hobart P ark (27 .73 660'N, 80.44298'W), IX-22 -93, the gonocoxite has 3 rods (setae a, b, c), a flattened 1 9, rX-30-03,4 9, X-13-03, I 9, X-16-03, I I, filament, a leaf, and a long, slender seta (setae f, g, X-2O-O3, 17 9 , ex exit trap (P Baffino); Sebastian, h); furthermore, the lateral plate of the phallosome Graves Swamp (27.44657"N, 80.92130'W), X-7- has l-4 large, very robust teeth with rounded api- 03, I 9 (P Bafflno). They are in the reference col- ces. In the male genitalia of Cx. nigripalpus, t}re lection of the Florida Medical Entomology Labo- subapical lobe has 3 rods (a, b, c), a leaf, and a ratory; Monroe County: Key Largo, Crocodile Lake strong seta (setae g, h) but lacks the extra flattened (25.1428"N,80"W),X-23-O3,2 9, XI-13-03,2 9, filament (seta f). Also, the lateral plate of the phal- XI-20-03, 9 I (D. DeMay); Big Pine Key losome has 2-6 smaller teeth, more slender and (24.6678'N, 81.3563'W), XI-25-03, 1 9; Long Key pointed apically. The pupa of Cx. declarator is (24.7217"N,61.0832'W), XI-25-O3, 1 9, ex ABC darkly pigmented and setae 5-Y VI are longer than trap (L. Hribar). the following segment. Culex nigripalpus pupae are More than 300 adults of Cx. declarator in 45 Iight tan with some darker brown spots and setae separate collections have been recorded in Indian 5-V VI are shorter than the following segment. The River County, Florida, as of XI-30-2003; see Thble 1. larvae of Cx. declarator are unique in having only In the various collections summarized in Table 3 pairs of siphonal setae and seta l-M much longer l, Cx. declaratorhas been associated with the fol- than seta 2-M, while Cx. nigripalpas larvae have 4 lowing species: Anopheles crucians Wiedemann, pairs of siphonal setae and seta l-M is subequal to Anopheles quadrimacularas Say sl, Aedes albopic- seta 2-M. ars (Skuse), Aedes vexans (Meigen), Coquillettidia The public health importance of Cx. declarator perturbans (Walker), Culex erraticas (Dyar and in other areas of the Americas has been reported. Knab), Cx. nigripalpus, Culex pilosus (Dyar and Aitken et al. (1964 as Cx. virgultus,1969 as Cx. Knab), Culex quinquefasciatus Say, Culex salinar- declarator) have recorded 4 separate isolations of las Coquillett, Deinocerites cancer Theobald, Man' St. Louis encephalitis virus from pools of Cx. de- sonia dyari Belkin, Heinemann and Page, Manso- clarator in Trinidad, along with I isolation of Tur- nia titillans (Walker), Ochlerotatus atlanticus (Dyar lock virus. At least I St. Louis encephalitis virus and Knab), Ochlerotatus infirmatus (Dyar and isolate has been made from Cx. declarator in Brazil A SsprBNlssn 2004 Cutsx oncLA,RAToa DIscovERED nl FLoRIDA 227

(Monath et at. 1980). Isolates of an unidentified Clark-Gil S, Darsie RF Jr. 1983. The mosquitoes of Gua- 15:151-284. Corriparta serogroup orbivirus have reportedly temala. Mosq Syst Darsie RF Jr., Ward RA. 1981. Identification and geo- been obtained from Cx. declarator in Brazil (Gor- graphical distribution of the mosquitoes of North Amer- 1983). man et al. ica, north of Mexico. Fresno, CA: American Mosquito The authors are aware of only 1 experimental Control Association. evaluation of this species as a potential arbovirus Dodge HR. 1963. Studies on mosquito larvae I. Later in- vector. Turell (1999) attempted to evaluate vector stars of eastem North American species. Can Entomol competence for Venezuelan equine encephalitis, 95:796-813. epizootic subtype IC. In contrast with more suscep- Dodge HR. 1966. Studies on mosquito larvae II. The first tible species tested, only 1 of 28 females feeding stage larvae of North American Culicidae and of world -393. on viremic hamsters was infected, and that infec- Anophelinae. Can Entomol 98:337 mosquitoes of the Americas Wash- tion was limited to midgut tissues. This suggested Dyar HG. 1928. The ington, DC: Carnegie Institute. Publication 387. 616 p. that Cx. declarator was essentially refractory to in- Fisk FW, LeVan JH. 1941. Mosquito collections at the oral route. fection with this virus by Brownsville, Texas. "/ Econ Entomol 33:944-945. Labarthe et al. (1998) considered Cx. declarator Forattini OP 1965. Entomologia medica Yoltme 2. Sao to be a potential vector of , dog Paulo: Editora Univ. Sao Paulo. 506 p. heartworm, as it was among the 4 most common Galindo P, Carpenter SJ, Trapido H. 1951. Ecological ob- mosquito species attracted to dog-baited traps in the servations on forest mosquitoes of an endemic yellow state of Rio de Janeiro, Brazil. They also found that fever area in Panama. Am J Trop Med Hyg 3l:98-137. host-seeking females were attracted to feline and Gorman BM, Taylor J, Walker PJ. 1983. Orbiviruses. In: human baits. Joklik WK, ed. The Reoviridae New York: Plenum Pub- lishing Co. p 287-351. Kline DL. 1999. Comparison of two American biophysics ACKNOWLEDGMENTS mosquito traps: the professional and a new counterflow geometry trap. J Am Mosq Control Assoc 75:276-282. The authors are indebted to Judy W. Knight, Pat- Knight KL, Stone A. 1977. A catalog of the mosquitoes rick Morgan, Paul Baffino, and Hilda Lynn for of the world (Diptera: Culicidae) Volume 6. College making the collections, to Nasar Hussain and James Park, MD: Thomas Say Foundation. Almasi for technical assistance, to Michelle Cutwa Kumm HW, Komp WHW, Ruiz H. 1940. The mosquitoes for the color illustrations, and to G. F O'Meara and of Costa Rica. Am J Trop Med 2O:385-422. Kumm HW, Zuniga H. 1942. The mosquitoes of El J. F Day for reviewing the manuscript. This is Flor- Sal- vador. Am J Trop Med 22:399-415. ida Agricultural Experiment Station Journal Series Labarthe N. Serrao ML, Melo YE de Oliveira SJ. Lou- no. R-09848. renco-de-Oliveira R. 1998. Mosquito frequency and feeding habits in an exotic canine dirofilariasis area of REFERENCES CITEI) Niteroi, State of Rio de Janeiro, Brazil. Mem Inst Os- waldo Cruz93:145-154. Aitken THG. 1967. The canopy-frequenting mosquitoes Lane J. 1953. Neotropical Culicidae,2 volumes. Sao Pau- of Bush forest, Trinidad, West Indies. A tas do Symposio lo, Brazil: Univ. Sao Paulo. sobre a biota Arnazonica (Patologia) 6:65-73. Matheson R. 1944. Handbook of the mosquitoes North Aitken THG, Downs WG, Spence L, Jonkers AH. 1964. Amertca Ithaca, NY: Comstock Publishing Company. St. Louis encephalitis virus isolations in Trinidad, West Monath TP, Cropp CB, Bowen GS, Kemp GE, Mitchell Indies, 1953-1962. Am Trop J Med Hyg 13:450-451. CJ, Gardner JJ. 1980. Variation in virulence for mice Aitken THG, Spence L, Jonkers AH, Downs WG. 1969. and rhesus monkeys among St. Louis encephalitis virus A l0-year survey of Trinidadian for natural strains of different origin. Am J Trop Med Hyg 29:948- virus infections (1953-1963). J Med Entomol 6:20'7- 962. 215. Stone A. 1956. Corrections in the and nomen- Arnett RH, Jr. 1948. Notes on the distribution, habits, and clature of mosquitoes. Proc Entomol Soc Wash 58:333- habitats of some Panama culicines (Diptera: Culicidae). J+J. J N Y Entomol Soc 56:l'75-193. Stone A. I 969. Bredin-Archbold-Smithsonian biological Bonne C, Bonne-Wepster J. 1925. Mosquitoes of Surinam survey of Dominica: the mosquitoes of Dominica (Dip- Royal Colonial Institute of Amsterdam, Afdeeling Tio- tera: Culicidae). Smithsonian Contrib to Zool 16:8. pische Hygiene no. 13. 558 p. Texas State Health Department. 7944. The mosquitoes of Bram RA. 1967. Classification of Culex subs.enus Culex Texas. Compiled by Division of Medical Entomology, in the New World (Diptera: Culicidae). Proc US Nat Division Laboratory, Texas State Health Department, Hist Mus 120G557):l-122. Austin, Texas. 100 p. Breland OP 1953. Keys to the larvae of Texas mosquitoes Turell MJ. 1999. Vector competence of three Venezuelan with notes on recent synonymy IL The genus Czlex mosquitoes (Diptera: Culicidae) for an epizootic IC Linnaeus. Tx J Sci 5: I l4-1 19. strain of Venezuelan equine encephalitis vints. J Med Breland OP 1954. Notes on the Culex virgultus complex Entomol 36:407-4O9. (Diptera: Culicidae)- Mosq News 14:68-71. Yamaguti S, LaCasse WJ. 1951 . Mosquito fauna of North Carpenter SJ, LaCasse WJ. 1955. Mosquitoes of North America. Part lV-Genera Culex and Deinocerites. Of- America (north of Mexico) Berkeley, CA: Univ. Cali- fice Surgeon, Headquarters Japan Logistical Command, fomia Press. US Army. 136 p.