diff --git a/atlas/modeles/repositories/vmObservationsMaillesRepository.py b/atlas/modeles/repositories/vmObservationsMaillesRepository.py
index d2ec6fdc6..b1b427ba9 100644
--- a/atlas/modeles/repositories/vmObservationsMaillesRepository.py
+++ b/atlas/modeles/repositories/vmObservationsMaillesRepository.py
@@ -93,42 +93,45 @@ def lastObservationsMailles(connection, mylimit, idPhoto):
     return obsList
 
 
-def lastObservationsCommuneMaille(connection, mylimit, insee):
+def lastObservationsCommuneMaille(connection, obs_limit, insee_code):
     sql = """
     WITH last_obs AS (
         SELECT
-            obs.cd_ref, obs.dateobs, t.lb_nom,
-            t.nom_vern, obs.the_geom_point AS l_geom
-        FROM atlas.vm_observations obs
-        JOIN atlas.vm_communes c
-        ON ST_Intersects(obs.the_geom_point, c.the_geom)
-        JOIN atlas.vm_taxons t
-        ON  obs.cd_ref = t.cd_ref
-        WHERE c.insee = :thisInsee
+            obs.id_observation, obs.cd_ref, obs.dateobs,
+            COALESCE(t.nom_vern || ' | ', '') || t.lb_nom  AS display_name,
+            obs.the_geom_point AS l_geom
+        FROM atlas.vm_observations AS obs
+            JOIN atlas.vm_communes AS c
+                ON ST_Intersects(obs.the_geom_point, c.the_geom)
+            JOIN atlas.vm_taxons AS t
+                ON obs.cd_ref = t.cd_ref
+        WHERE c.insee = :inseeCode
         ORDER BY obs.dateobs DESC
-        LIMIT :thislimit
+        LIMIT :obsLimit
     )
-    SELECT l.lb_nom, l.nom_vern, l.cd_ref, m.id_maille, m.geojson_maille
-    FROM atlas.t_mailles_territoire m
-    JOIN last_obs  l
-    ON st_intersects(m.the_geom, l.l_geom)
-    GROUP BY l.lb_nom, l.cd_ref, m.id_maille, l.nom_vern, m.geojson_maille
+    SELECT
+        l.id_observation, l.cd_ref, l.display_name, m.id_maille, m.geojson_maille
+    FROM atlas.t_mailles_territoire AS m
+        JOIN last_obs AS l
+            ON st_intersects(m.the_geom, l.l_geom)
+    GROUP BY l.id_observation, l.cd_ref, l.display_name, m.id_maille, m.geojson_maille
+    ORDER BY l.display_name
     """
-    observations = connection.execute(text(sql), thisInsee=insee, thislimit=mylimit)
-    obsList = list()
-    for o in observations:
-        if o.nom_vern:
-            taxon = o.nom_vern + " | " + "<i>" + o.lb_nom + "</i>"
-        else:
-            taxon = "<i>" + o.lb_nom + "</i>"
-        temp = {
-            "cd_ref": o.cd_ref,
-            "taxon": taxon,
-            "geojson_maille": json.loads(o.geojson_maille),
-            "id_maille": o.id_maille,
+    results = connection.execute(
+        text(sql), inseeCode=insee_code, obsLimit=obs_limit
+    )
+    observations = list()
+    for r in results:
+        # taxon = (r.nom_vern + " | " + r.lb_nom) if r.nom_vern else r.lb_nom
+        infos = {
+            "cd_ref": r.cd_ref,
+            "taxon": r.display_name,
+            "geojson_maille": json.loads(r.geojson_maille),
+            "id_maille": r.id_maille,
+            "id_observation": r.id_observation,
         }
-        obsList.append(temp)
-    return obsList
+        observations.append(infos)
+    return observations
 
 
 # Use for API
diff --git a/atlas/static/mapGenerator.js b/atlas/static/mapGenerator.js
index 58c5892cb..2134cde03 100644
--- a/atlas/static/mapGenerator.js
+++ b/atlas/static/mapGenerator.js
@@ -435,7 +435,6 @@ function onEachFeaturePointLastObs(feature, layer) {
     popupContent +
       "</br> <a href='" +
       configuration.URL_APPLICATION +
-
       language +
       "/espece/" +
       feature.properties.cd_ref +
@@ -546,7 +545,7 @@ function compare(a, b) {
   return 0;
 }
 
-function printEspece(tabEspece, tabCdRef) {
+function buildSpeciesEntries(tabEspece, tabCdRef) {
   stringEspece = "";
   i = 0;
   while (i < tabEspece.length) {
@@ -567,11 +566,12 @@ function printEspece(tabEspece, tabCdRef) {
 function onEachFeatureMailleLastObs(feature, layer) {
   // Add class to be able to scroll the species list
   popupContent =
-    "<b>Espèces observées dans la maille: </b> <div class=\"species-grid-popup\"><ul> " +
-    printEspece(feature.properties.list_taxon, feature.properties.list_cdref) +
-    "</ul></div>";
+    "<b>" + feature.properties.list_taxon.length + " espèces observées dans la maille&nbsp;: </b>" +
+    "<ul> " +
+      buildSpeciesEntries(feature.properties.list_taxon, feature.properties.list_cdref) +
+    "</ul>";
 
-  layer.bindPopup(popupContent);
+  layer.bindPopup(popupContent, { maxHeight: 300 });
 }
 
 function styleMailleLastObs() {
@@ -584,37 +584,28 @@ function styleMailleLastObs() {
 }
 
 function generateGeoJsonMailleLastObs(observations) {
-  // sort it because at each change of idMaille, the
-  // list_taxon is reset so not all species are displayed
-  observations = observations.sort((a,b) => compare(a, b))
-  var i = 0;
-  myGeoJson = { type: "FeatureCollection", features: [] };
-  while (i < observations.length) {
-    geometry = observations[i].geojson_maille;
-    idMaille = observations[i].id_maille;
-    properties = {
-      id_maille: idMaille,
-      list_taxon: [observations[i].taxon],
-      list_cdref: [observations[i].cd_ref],
-      list_id_observation: [observations[i].id_observation],
-    };
-    var j = i + 1;
-    while (j < observations.length && observations[j].id_maille == idMaille) {
-      properties.list_taxon.push(observations[j].taxon);
-      properties.list_cdref.push(observations[j].cd_ref);
-      properties.list_id_observation.push(observations[j].id_observation);
-      j = j + 1;
+  var features = {};
+  observations.forEach((obs) => {
+    var key = `${obs.id_maille}`;
+    if (!Object.hasOwn(features, key) ) {
+      features[key] = {
+        "type": "Feature",
+        "geometry": obs.geojson_maille,
+        "properties": {
+          "id_maille": obs.id_maille,
+          "list_cdref": [obs.cd_ref],
+          "list_taxon": [obs.taxon],
+        }
+      };
+    } else if (!features[key]["properties"]["list_cdref"].includes(obs.cd_ref)) {
+      features[key]["properties"]["list_cdref"].push(obs.cd_ref);
+      features[key]["properties"]["list_taxon"].push(obs.taxon);
     }
-    myGeoJson.features.push({
-      type: "Feature",
-      properties: properties,
-      geometry: geometry,
-    });
-    // on avance jusqu' à j
-    i = j;
-  }
+  });
 
-  return myGeoJson;
+  geoJson = { type: "FeatureCollection", features: [] };
+  Object.keys(features).forEach((idMaille) => geoJson.features.push(features[idMaille]));
+  return geoJson;
 }
 
 function find_id_observation_in_array(tab_id, id_observation) {