Know more

About cookies

What is a "cookie"?

A "cookie" is a piece of information, usually small and identified by a name, which may be sent to your browser by a website you are visiting. Your web browser will store it for a period of time, and send it back to the web server each time you log on again.

Different types of cookies are placed on the sites:

  • Cookies strictly necessary for the proper functioning of the site
  • Cookies deposited by third party sites to improve the interactivity of the site, to collect statistics

Learn more about cookies and how they work

The different types of cookies used on this site

Cookies strictly necessary for the site to function

These cookies allow the main services of the site to function optimally. You can technically block them using your browser settings but your experience on the site may be degraded.

Furthermore, you have the possibility of opposing the use of audience measurement tracers strictly necessary for the functioning and current administration of the website in the cookie management window accessible via the link located in the footer of the site.

Technical cookies

Name of the cookie


Shelf life

CAS and PHP session cookies

Login credentials, session security



Saving your cookie consent choices

12 months

Audience measurement cookies (AT Internet)

Name of the cookie


Shelf life


Trace the visitor's route in order to establish visit statistics.

13 months


Store the anonymous ID of the visitor who starts the first time he visits the site

13 months


Identify the numbers (unique identifiers of a site) seen by the visitor and store the visitor's identifiers.

13 months

About the AT Internet audience measurement tool :

AT Internet's audience measurement tool Analytics is deployed on this site in order to obtain information on visitors' navigation and to improve its use.

The French data protection authority (CNIL) has granted an exemption to AT Internet's Web Analytics cookie. This tool is thus exempt from the collection of the Internet user's consent with regard to the deposit of analytics cookies. However, you can refuse the deposit of these cookies via the cookie management panel.

Good to know:

  • The data collected are not cross-checked with other processing operations
  • The deposited cookie is only used to produce anonymous statistics
  • The cookie does not allow the user's navigation on other sites to be tracked.

Third party cookies to improve the interactivity of the site

This site relies on certain services provided by third parties which allow :

  • to offer interactive content;
  • improve usability and facilitate the sharing of content on social networks;
  • view videos and animated presentations directly on our website;
  • protect form entries from robots;
  • monitor the performance of the site.

These third parties will collect and use your browsing data for their own purposes.

How to accept or reject cookies

When you start browsing an eZpublish site, the appearance of the "cookies" banner allows you to accept or refuse all the cookies we use. This banner will be displayed as long as you have not made a choice, even if you are browsing on another page of the site.

You can change your choices at any time by clicking on the "Cookie Management" link.

You can manage these cookies in your browser. Here are the procedures to follow: Firefox; Chrome; Explorer; Safari; Opera

For more information about the cookies we use, you can contact INRAE's Data Protection Officer by email at or by post at :


24, chemin de Borde Rouge -Auzeville - CS52627 31326 Castanet Tolosan cedex - France

Last update: May 2021

Menu Logo Logo Union Europeenne Partenaires COLBICS

FP7 Marie Curie IAPP - Colbics - Project

FP7 Marie Curie IAPP - Colbics Project

Wing shape, a tool to discriminate Trichogramma species

Wing geometry to discriminate Trichogramma species

Morphological identification of the most species of Trichogramma is difficult due to their small size and overlap of potentially diagnostic characters. Almost all of the diagnostic characters for Trichogramma are found on the antennal flagellum or on the genitalia of males. Female Trichogramma have been usually considered “unidentifiable”. This can be a problem regarding that most species of Trichogramma have a biased sex-ratio (females more common than males) or are thelytokous.

In the context of COLBICS, the mixed INRA-IAS-ANASAC R&D team carried out an exploratory study aiming to detect variations on the shape of wing between several Trichogramma species using geometric morphometrics approaches. In fact, landmark-based geometric morphometrics is a powerful approach to quantifying biological shape, shape variation, and covariation of shape with biotic or abiotic variables or factors. More precisely, landmark-based geometric involves summarizing shape in terms of a landmarks configuration (constellation of discrete anatomical loci, each described by 2 ou 3 dimensional Cartesian coordinates). Thus, this method allows drawing evocative diagrams of morphological transformations or differences, and offering an immediate visualization of shape and the spatial localization of shape variation.

The differences in wing shape between 4 species of Trichogramma: T. brassicae (N=20), T. semblidis (N= 11), T. achaeae (N=9), T. cacoeciae (N=15) were studied. Initially, 7 landmarks (LM) and 12 semi-landmarks (SL) were defined and Cartesian coordinates (x and y) for each LM and SL of the wings were obtained. After, a Procrustes Superimposition on the Cartesian coordinates, and a Principal Component analysis on the superimposed coordinates, a UPGMA cluster analysis based on squared Mahalonobis distances derived from the first axes of the PCA were done. The UPGMA cluster analysis revealed high significantly dissimilarities in wing shape between T. brassicae, T. semblids, T. achaeae and T. caceociae.

This preliminary study suggest that wing geometry can be a good tool for discriminate some Trichogramma species. In fact, comparing to wing size, wing shape have different genetic properties, size heritability being generally low, while wing shape is less sensitive to environmental changes and highly heritable. Moreover, assuming that wing shape can be related to flight ability for example, we can imagine that using geometric morphometrics on Trichogramma wings can also be a good tool for correlate dispersion efficacy of strains on field and their wing shape for example.

Procruste surperimposition

Different steps of the Procruste Superimposition : Scaling, Transposition, Rotation


Different locations of LM (blue points) and SL (red square) on the forewing of T. semblidis


UPGMA Tree of the UPGMA Cluster Analysis

See also

Geometric Morphometrics: Ten Years of Progress Following the ‘Revolution’

MoMe-CLIC : Morphometrics in Medical Entomology-Collection of Landmark for identification and characterization (By J.P Dujardin)