diff --git a/DESCRIPTION b/DESCRIPTION
index 6cb646a5d..786d353e3 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -1,5 +1,5 @@
 Package: AMR
-Version: 3.0.1.9079
+Version: 3.0.1.9080
 Date: 2026-06-27
 Title: Antimicrobial Resistance Data Analysis
 Description: Functions to simplify and standardise antimicrobial resistance (AMR)
diff --git a/NEWS.md b/NEWS.md
index 06b1b43b2..0d470520a 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -1,4 +1,4 @@
-# AMR 3.0.1.9079
+# AMR 3.0.1.9080
 
 Planned as v3.1.0, end of June 2026.
 
@@ -32,6 +32,7 @@ Planned as v3.1.0, end of June 2026.
 * `as.mo()`: 
   * Input of the form `"X complex"` now falls back to `"X"` when the complex is not a distinct taxon in the database, preventing `NA` results for valid clinical descriptions such as `"Proteus vulgaris complex"` (#287)
   * Abbreviated-genus input (e.g. `"S. apiospermum"`) now correctly ranks candidates whose species epithet exactly matches the input above more-prevalent organisms whose species does not match; fixes `"S. apiospermum"` resolving to *Staphylococcus* instead of *Scedosporium apiospermum* (#288)
+  * Abbreviated-genus input for species that have subspecies (e.g. `"P. ovale"`) now collapses to the species-rank record instead of incorrectly matching a more-prevalent organism; explicit subspecies queries (e.g. `"P. ovale curtisi"`) are preserved (#288)
 * `get_author_year()` in the microorganism reproduction script now strips `emend.` and everything after it, so `ref` reflects the combination authority rather than the emendation author (e.g. *Rhodococcus equi* now returns "Goodfellow et al., 1977" instead of "Nouioui et al., 2018")
 * BRMO classification now includes bacterial complexes (#275)
 * Translation fixes for Italian CoNS/CoPS names (#256), Dutch antimicrobials, and `sir_df()` foreign-language output (#272)
diff --git a/R/mo.R b/R/mo.R
index e80c7b5a2..5a5c81217 100755
--- a/R/mo.R
+++ b/R/mo.R
@@ -352,16 +352,34 @@ as.mo <- function(x,
             (MO_lookup_current$species_first == substr(x_parts[2], 1, 1) |
               MO_lookup_current$subspecies_first == substr(x_parts[2], 1, 1) |
               MO_lookup_current$subspecies_first == substr(x_parts[3], 1, 1)))
-          # Issue #288: if the species (and subspecies) word(s) in the input exactly match
-          # exactly one candidate, use only that candidate and bypass the 0.55 cutoff.
-          # This prevents prevalent bacteria from outranking a rarer organism whose species
-          # epithet is an unambiguous exact match, e.g. "S. apiospermum" → Scedosporium.
+          # Issue #288 (extended): if the species (and subspecies) word(s) in the input
+          # exactly match candidates that all belong to one and the same genus, bypass the
+          # 0.55 cutoff. A species together with its subspecies/autonyms (e.g. Plasmodium
+          # ovale + curtisi + wallikeri) is the same taxon, so for a genus+species input we
+          # collapse to the species-rank record (subspecies == ""). This prevents prevalent
+          # bacteria from outranking a rarer organism whose species epithet is an
+          # unambiguous exact match, e.g. "S. apiospermum" -> Scedosporium, "P. ovale" ->
+          # Plasmodium ovale. If two different genera share the epithet, the genus check
+          # stays FALSE and the normal matching score arbitrates.
           sp_exact <- tolower(MO_lookup_current$species[filtr]) == x_parts[2]
           if (length(x_parts) == 3) {
             sp_exact <- sp_exact & tolower(MO_lookup_current$subspecies[filtr]) == x_parts[3]
           }
-          if (sum(sp_exact) == 1) {
-            filtr <- filtr[sp_exact]
+          exact_idx <- filtr[sp_exact]
+          if (length(exact_idx) >= 1 &&
+            length(unique(MO_lookup_current$genus_lower[exact_idx])) == 1) {
+            if (length(x_parts) == 2) {
+              # genus + species only: collapse to the species-rank record (subspecies == "")
+              is_species_rank <- MO_lookup_current$subspecies[exact_idx] == ""
+              if (any(is_species_rank)) {
+                filtr <- exact_idx[is_species_rank][1]
+              } else {
+                filtr <- exact_idx[1]
+              }
+            } else {
+              # explicit subspecies given, unambiguous within the genus
+              filtr <- exact_idx[1]
+            }
             minimum_matching_score <- 0
           }
         } else {
diff --git a/tests/testthat/test-data.R b/tests/testthat/test-data.R
index 5b4a787bd..babe42e81 100644
--- a/tests/testthat/test-data.R
+++ b/tests/testthat/test-data.R
@@ -142,3 +142,9 @@ test_that("test-data.R", {
   # x <- check_non_ascii() %>%
   #   filter(file %unlike% "^(data-raw|docs|git_)")
 })
+
+test_that("taxonomic name columns contain no NA (empty string is used instead)", {
+  for (col in c("domain", "kingdom", "phylum", "class", "order", "family", "genus", "species", "subspecies")) {
+    expect_false(anyNA(microorganisms[[col]]), info = col)
+  }
+})
diff --git a/tests/testthat/test-mo.R b/tests/testthat/test-mo.R
index 3f98ec6b5..49a90e5e8 100644
--- a/tests/testthat/test-mo.R
+++ b/tests/testthat/test-mo.R
@@ -338,3 +338,30 @@ test_that("test-mo.R", {
     )
   }
 })
+
+test_that("as.mo() resolves abbreviated genus when species carries subspecies (#288 follow-up)", {
+  # "P. ovale" must resolve to Plasmodium ovale, not a Pseudomonas species,
+  # even though P. ovale has subspecies (curtisi, wallikeri) sharing the epithet.
+  expect_identical(
+    as.mo("P. ovale", keep_synonyms = TRUE, info = FALSE),
+    as.mo("Plasmodium ovale", keep_synonyms = TRUE, info = FALSE)
+  )
+  expect_identical(
+    mo_name("P. ovale", keep_synonyms = TRUE, language = NULL),
+    "Plasmodium ovale"
+  )
+
+  # Non-regression: the original #288 example must still work.
+  expect_identical(
+    mo_genus("S. apiospermum", keep_synonyms = TRUE, language = NULL),
+    "Scedosporium"
+  )
+
+  # Explicit subspecies must not be collapsed to species rank.
+  if (any(microorganisms$fullname == "Plasmodium ovale curtisi")) {
+    expect_identical(
+      mo_name("P. ovale curtisi", keep_synonyms = TRUE, language = NULL),
+      "Plasmodium ovale curtisi"
+    )
+  }
+})