Slipping through the Cracks: The Taxonomic Impediment Conceals the Origin and Dispersal of Haminoea japonica, an Invasive Species with Impacts to Human Health

Abstract

Haminoea japonica is a species of opisthobranch sea slug native to Japan and Korea. Non-native populations have spread unnoticed for decades due to difficulties in the taxonomy of Haminoea species. Haminoea japonica is associated with a schistosome parasite in San Francisco Bay, thus further spread could have consequence to human health and economies. Anecdotal evidence suggests that H. japonica has displaced native species of Haminoea in North America and Europe, becoming locally dominant in estuaries and coastal lagoons. In this paper we study the population genetics of native and non-native populations of H. japonica based on mt-DNA data including newly discovered populations in Italy and France. The conclusions of this study further corroborate a Northeastern Japan origin for the non-native populations and suggest possible independent introductions into North America and Europe. Additionally, the data obtained revealed possible secondary introductions within Japan. Although non-native populations have experienced severe genetic bottlenecks they have colonized different regions with a broad range of water temperatures and other environmental conditions. The environmental tolerance of this species, along with its ability to become dominant in invaded areas and its association with a schistosome parasite, suggest H. japonica could be a dangerous invasive species.

Histological, histochemical, and ultrastructural investigation of the male copulatory apparatus of Haminoea navicula (Gastropoda, Cephalaspidea)

“…These data hint at a possible different genetic affiliation of Indo‐Pacific species, but this remains to be proved. Unfortunately, an available phylogenetic hypothesis including a larger number of worldwide Haminoea species, based on one mitochondrial gene and one nuclear gene (COI and 28S rRNA), does not allow to test of the monophyly of the genus Haminoea because other genera of Haminoeidae were not included (Hanson et al, ). Thus, a more comprehensive phylogenetic study of the family Haminoeidae and Haminoea genus ( sensu Burn & Thompson, ) including better gene coverage and morphological characters will be necessary to clarify the monophyly and evolution of morphological traits in these snails.…”

“…In addition to the native species, H. japonica , Pilsbry, 1895 (= H . callidegenita ) and H. cyanomarginata , Heller and Thompson, 1983 from the Indo‐Pacific oceans, were reported on European coasts (Crocetta & Vazzana, ; Hanson et al, ).…”

“…It is found in the Mediterranean Sea and in the Atlantic from southern England and Ireland to the Strait of Gibraltar, living on softsediment bottoms from intertidal areas down to a depth of 4 m in coastal lagoons and estuaries (Malaquias & Cervera, 2006). In addition to the native species, H. japonica, Pilsbry, 1895 (5 H. callidegenita) and H. cyanomarginata, Heller and Thompson, 1983 from the Indo-Pacific oceans, were reported on European coasts (Crocetta & Vazzana, 2009;Hanson et al, 2013).…”

Adriatic ‘opisthobranchs’ (Gastropoda, Heterobranchia): shedding light on biodiversity issues

“…; Hanson et al . ; Giacobbe & De Matteo ). Amongst the latest alien arrivals in the Adriatic Sea, Melibe viridis (Kelaart, 1858) is only known from Croatia and Montenegro.…”

“…For taxa lacking a recent taxonomic revision, lists of species names may not be based on sound taxonomy, and downstream inferences may be erroneous. Indeed, taxonomic revisions complemented by molecular analyses are the only rigorous way to address the status of all available species names (Dayrat 2011; Pola et al 2012;Carmona et al 2013;Hanson et al 2013;. Following Dayrat (2011), major problematic species names have been flagged in our checklist, so that non-taxonomists will know that those names should be used with caution or not at all.…”