The Australian National System for the Prevention and Management of Introduced Marine Pest Incursions has identified seven Harmful Algal Bloom (HAB) toxic dinoflagellate species as target species of concern. Alexandrium minutum Halim, 1960, and Alexandrium cf. tamarense (Lebour) Balech, 1995, are currently known to occur in south-western estuaries and coastal waters but with no documented impact on the seafood industry or human health. Monitoring of these species is challenging, time-consuming, expensive, and often relies on traditional morphotaxonomy. This reports the first confirmed detection of another HAB species, Alexandrium catenella (Whedon and Kofoid) Balech, 1995, in Western Australia (WA), using both microscopic and molecular methods. The confirmed detection of A. catenella (A. pacificum Group IV genotype) in WA hopefully will motivate discussion about better monitoring and control of toxic HAB species.

Sargassum horneri (Turner) C. Agardh, 1820 is a fast growing brown alga native to shallow reefs of eastern Asia. It has spread aggressively throughout southern California, USA, and Baja California, México since it was discovered in the eastern Pacific in 2003 and poses a major threat to the sustainability of native marine ecosystems in this region. Here we present a chronology of the rapid geographic expansion of S. horneri in the eastern Pacific and discuss factors that potentially influence its spread.

The yellow flag iris, Iris pseudacorus L., was recorded for the first time outside of cultivation in South Africa along the Vaal River in Gauteng Province in 2004. The yellow flag iris is native to Eurasia and North Africa and was probably introduced to South Africa as an ornamental plant. We recorded I. pseudacorus in four of the nine provinces of South Africa, with naturalised populations at 24 localities covering an estimated area of about 0.4 ha around rivers, streams, dams and wetlands. While we found it at multiple sites (suggesting the species should be classified as category E in South Africa under the Blackburn scheme), the current planted and naturalised distribution throughout South Africa and neighboring countries is likely to be substantially higher than reported here. Infestations are likely to cause substantial negative impacts as seen elsewhere in the world. The species is currently listed as an eradication target under South African regulations, but the feasibility of control still needs to be determined and given its popularity, eradication from the region looks unlikely.

The warm water marine bryozoan Amathia (= Zoobotryon) verticillata (delle Chiaje, 1822) is reported for the first time in the Galápagos Islands based upon collections in 2015. Elsewhere, this species is a major fouling organism that can have significant negative ecological and economic effects. Comprehensive studies will be necessary to determine the extent of the distribution of A. verticillata in the Galápagos and its effects on native species. The establishment of A. verticillata emphasizes the need for regular monitoring of those vectors that could bring additional non-native species to the Archipelago.

It is important to keep lists of invasive and alien species up to date, but it can be difficult to determine when species should be removed from such lists. One such example is the urchin, Tetrapygus niger (Molina, 1782), which is believed to have been unintentionally introduced to Alexander Bay on the west coast of South Africa with oyster spat imported for aquaculture (the only recorded alien population of T. niger globally). This species is a kelp grazer in its native range, capable of converting healthy kelp populations to barren landscapes. This study involved the re-survey of two aquaculture dams in September 2014, which previously contained the urchin, as well as intertidal and subtidal transects of the surrounding coast. Tetrapygus niger were absent from all sites, despite the presence of a healthy population of native urchins Parechinus angulosus (Leske, 1778). There was also little indication of urchin grazing on kelp stipes. As a result of this absence record, it is recommended that T. niger be removed from the South African list of introduced marine species, and from global lists of invasive species.

The non-native Asian fish tapeworm Bothriocephalus acheilognathi was registered for the first time in 2008–2009 in a threatened Mexican fish Profundulus candalarius. From June 2008 to April 2009 the overall prevalence of the cestode in the fish intestines was around 35% (N = 242 P. candalarius examined). Unstrobilized and inmature cestodes formed the greatest proportion (91.07%) of the parasite population. Neither the prevalence, nor the mean intensity varied significantly with host sex. Smaller fish (10–29 mm) were parasitized more frequently than medium size fish (30–59 mm), prevalence 43.5% vs 27.3%. Although, the cestodes’ monthly prevalence and mean intensity per host varied from 18 to 70 percent and from 2.75 to 9.27 respectively, no significant seasonal difference was found. There was a continuous recruitment of cestodes within the host population, as well as a nearly continuous growth and maturation of the parasites to adults. Most cestodes are lost from the host as development of parasites proceeds, and only 12 of the 437 collected tapeworms reached gravidity. The most important features of the data presented here include the confirmation that B. acheilognathi can reproduce in Mexico.

During the helminthological survey of non-native fishes in Meerut region, UP, India, specimens of genus Bothriocephalus were collected from introduced fish green swordtail Xiphophorus hellerii Heckel, 1848, a native of North and Central America. The morphological and molecular study inferred with partial sequence of 18S and 28S rRNA confirmed the specimens as B. acheilognathi. Phylogenetic analysis further confirmed its taxonomic status, as it comes under same clade formed by B. acheilognathi species reported from other geographical regions. This study first describes the molecular identification of B. acheilognathi from India. The findings of study also established its presence in ecologically impacted northern parts of India and highlight that low specificity for host can affect the native fish resources of India.

This study presents the first record of Martesia striata (Linnaeus, 1758) in the Mediterranean Sea. It was detected during a routine monitoring study in the Iskenderun Bay, Turkey. The potential for M. striata to establish permanent population in the Mediterranean Sea and possible risks that might arise from such a situation were briefly discussed.

The blue crab Callinectes sapidus (Rathbun, 1896), a native to western Atlantic coasts, is widely recorded in various Mediterranean regions, including the Gargano lagoons in the Adriatic Sea. This study investigated selected biological traits of Callinectes sapidus females in the Lesina and Varano lagoons during their breeding migration to more saline waters. In total, 19 individuals of Callinectes sapidus, 15 females and four males, were collected in the lagoons near the mouths of the seaward channels. The specimens’ Carapace Width ranged from 115 to 230 mm, classifying them as medium to large crabs. In Varano lagoon in April and May 2014, two ovigerous females with egg masses of 63.39 g and 11.65 g respectively were captured. This represents the first record of ovigerous females of C. sapidus in this lagoon. The average Gonado-Somatic Index was 2.91±1.82 and 1.65±0.65 for the specimens captured in Varano and Lesina lagoons, respectively. The average Hepato-Somatic Index was 3.88±0.80 and 4.22±0.31 for specimens captured in Varano and Lesina, respectively. Egg diameter ranged between 0.23 and 0.35 mm. Histological analysis of gonads showed stages from III to V, with individuals in emission or post-issuance stages. This study presents evidence of the establishment of C. sapidus populations in Varano lagoon in the south-west Adriatic Sea and provides additional information on this species in the Lesina and Varano lagoons.

Percnon gibbesi is the most invasive decapod species to enter the Mediterranean Sea. A single specimen was photographed off the Israeli coast in 2009. In the past couple of years specimens, including ovigerous females, of this plagusiid crab were reported from several Israeli locations, suggesting the presence of a self-sustaining population in the southeast Mediterranean.

The Indian anchovy Stolephorus indicus (van Hasselt, 1823) was recorded for the first time in the Mediterranean near Tel-Aviv, Israel on 15 May 2015. This Indo-West Pacific species evidently reached the Mediterranean via the Suez Canal from the Red Sea. Several specimens of Stolephorus insularis were also collected, which suggests that species has established a viable population in the Levant.

The blue tang Acanthurus coeruleus Bloch and Schneider, 1801 and the Red Sea bannerfish Heniochus intermedius Steindachner, 1893 are reported for the first time from the Maltese Islands, which also represents the first central Mediterranean record for both species. The new records are based on an individual of A. coeruleus observed in October 2013 and a specimen of H. intermedius caught in November 2014; no individuals of either species have been found since. The occurrence of these species in Malta may be due to a westwards range expansion in the Mediterranean, given that both species were previously recorded from the Levantine Sea, but they could also have been introduced directly in Maltese waters through the aquarium trade or by shipping, particularly since evidence for established populations in the eastern Mediterranean is lacking. The relevance of these new additions of thermophilic fishes to the central Mediterranean ichthyofauna is discussed in relation to ongoing biotic changes in this sea.

Eight specimens of the slender ponyfish Equulites elongatus were collected, by otter trawl, between 6 December 2014 and 18 April 2015 from Turkish waters, off Mersin. This constitutes the second record of this species in the Mediterranean Sea and is about 530 km distant from the site of first record (Tel Aviv, Israel).

Non-native South American suckermouth armored catfishes brackish waters of the genus Pterygoplichthys are reported in the Chumpan River in the Southeastern Mexico. The Pterygoplichthys in the Chumpan likely dispersed from populations from the drainage of nearby coastal rivers where they were already established. These catfish tolerate estuarine conditions and probably dispersed from the Grijalva-Usumacinta basin through the brackish waters of Laguna de Términos and then ultimately entered the Chumpan River system. One juvenile and seven adult Pterygoplichthys were collected in the Chumpan River system in December 2014 from a river lagoon some 15 km upstream from Laguna de Términos. Non-native catfish were not detected in the nearby Candelaria River. Based on their ventral color patterns, the captured adult catfish were identified as a mix of Pterygoplichthys pardalis and hybrid Pterygoplichthys disjunctivus × pardalis. The detection of these invasive catfish in the Chumpan River highlights the urgent need to generate an awareness program to reduce any adverse effects of this invasive species in the basin, and raises concerns that they may disperse to other basins via an oligohaline passageway in Laguna de Términos.