CUTICULAR SENSORY RECEPTORS ON THE LEGS AND GENETALIA OF THE BED BUG, CIMEX LECTULARIUS (HEMIPTERA: CIMICIDAE): ULTRASTRUCTURE, MORPHOLOGY AND DISTRIBUTION PATTERNS

• Sponsoring Institution: National Institute of Food and Agriculture
• Project Status: COMPLETE
• Funding Source: HATCH
• Reporting Frequency: Annual
• Accession No.: 1014058
• Project Start Date: Oct 3, 2017
• Project End Date: Dec 18, 2020
• Program Code: [(N/A)]- (N/A)

Recipient Organization
MISSISSIPPI STATE UNIV
(N/A)
MISSISSIPPI STATE,MS 39762

Performing Department
Entomology & Plant Pathology

Non Technical Summary
providing basic information on a particular structure and to infer possible functional attributes. Information provided by morphological studies is used in other areas of research such as in physiology and behavior. It is well known that cuticular sensilla on the tarsi and genetalia of male and female insects extremely important in various physiological functions and behavior and this needs to be established before more advanced research such as electrophysiology can be carried out. Therefore this project will focus on the cuticular sensory receptors on the tarsi and genetalia of the bed bug, Cimex lectularis.

Animal Health Component

0%

Research Effort Categories

Basic

100%

Applied

0%

Developmental

0%

Classification

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
722	3110	1130	100%

Knowledge Area
722 - Zoonotic Diseases and Parasites Affecting Humans;

Subject Of Investigation
3110 - Insects;

Field Of Science
1130 - Entomology and acarology;

Keywords

insect morphology

bedbugs

cimicidae

cimex lectularis

sensilla

Goals / Objectives
To describe the morphology and ultrastructure and to map the distribution and numbers of sensilla on the legs and male and female genetalia of Cimex lectularius. To perform chemical choice tests on the adults and immatures that use chemical ablation of sensory receptors on the above mentioned body regions in order to provide more information toward sensillum functionality.?

Project Methods
For light microscopy, the crystal violet technique and the silver nitrate and cobalt chloride techniques will be used to detect porous sensilla on mouthparts, legs, and antenna. For scanning electron microscopy, specimens will be fixed in Karnowsky's fixative for four hours.A solution of 2 percent osmium tetraoxide will be used as the post-fixative. Specimens will be critical-point dried, mounted, and examined with a JEOL JSM 6500F scanning electron microscope. For Transmission Electron Microscopy, the same fixation procedure will be used, with samples embedded in Spurr's. After sectioning and stained, specimens will be examined with JEOL JEM-1230 TEM. For confocal laser scanning microscopy, three flurochromes will be used to detect the number of sensory neurons. For behavioral choice tests, the sensilla on the legs and genitalia will be blocked using a solution of N-methylmaleimide in absolute alcohol. Choice tests will be conducted with treated and untreated bugs and data will be subjected to statistical analysis.

Progress 10/01/20 to 12/18/20

Outputs
Target Audience: Nothing Reported Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest? Nothing Reported What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Progress was made towards objectives.

Publications

Progress 10/03/17 to 12/18/20

Outputs
Target Audience:Research scientists and graduate students at various research facilities Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest? Nothing Reported What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? The research on the senilla situated on the female and malegenital-anal regions has been completed. The female bed bug has only solid trichoid sensilla in this region which are typically mechano-receptorswhereas the male bed bughas stress and pressure receptor sensilla and and also contact chemoreceptors.

Publications

Progress 10/01/19 to 09/30/20

Outputs
Target Audience:The audience would be researchers and graduate students at universities and government research labs. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest? Nothing Reported What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? The morphology of the various types of cuticular sensilla that are situated in the genital region on the female and male bed bugs ( Cimex lectularius,Hemiptera: Cimicidae,) has beendescribed. The female bed bug only has solid trichoid sensilla on the genital area which are typical mechano-receptors whereas the the male bed bug has four distict types of sensilla on the apex of the abdomen where the male bed bug's intromittent organ is located. The apical edge of the deep invagination on the end of the abdomen that houses the intromittent organ has long, solid, trichoid sensilla that over-lap the opening of the invagination. There are three types of sensilla on the surface of the male's intromittent organ;1.dome shaped sensilla,2.round globular sensilla and 3.short, cuticlar pegs with a distinct apical pore.The trichoid,dome-shapedand globular senilla are probably various kinds of mechano-receptors and the peg sensillum with the apical pore is probably a contact chemo-receptor.The morphological descriptions arebeing used for a publication

Publications

Progress 10/01/18 to 09/30/19

Outputs
Target Audience:Research scientists at various universities and government labs. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest?The information on the citicular sensory receptors will be published in a journal. What do you plan to do during the next reporting period to accomplish the goals?Will work on sensilla on the legs of Cimex lectularius.

Impacts
What was accomplished under these goals? The morphology and distribution of the sensilla on the female and male genetalia and the anal opening of the bed bug ,Cimex lectularius(Cimicidae) has been completed and is being written up.

Publications

• Type: Journal Articles Status: Published Year Published: 2018 Citation: Baker,G.T. and Goddard,J.(2018).Structure and number of tibial brush setae making up the fossil spongiosa in bed bugs,Cimex lectularius L. (Hemiptera:Cimicidae).Proceedings of the Entomological Society of America 120:251-254.

Progress 10/03/17 to 09/30/18

Outputs
Target Audience:Research Scientists Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest?Publication in the Proc.Entomol. Wash. 120:251-254. What do you plan to do during the next reporting period to accomplish the goals?Plan to complete the morphological and ultrastuctural work on the legsensilla of bed bug adults and nymphs using the various microscopy techniques and begin work on sensilla found on the surface ofthe genitalia.

Impacts
What was accomplished under these goals? Preliminary work on the type,number and distribution of the senilla on the male and female adult legs was accomplished using SEM, TEM, and LMtechniques. Several types of mechano-sensory receptors and chemo- sensory receptors are distributed on the dorsal and ventral surfaces of the adult legs.

Publications

• Type: Journal Articles Status: Published Year Published: 2018 Citation: Baker,G.T. and Goddard,J.2018.Structure and number of tibial brush setae making up the fossula spongiose in bed bugs,Cimex lectularius L.,(Hemiptera:Cimicidae). Proceedings of the Entomological Society of Washington 120:251-254.