Diana S. Jones

The introduction to Japan of the Titan barnacle, Megabalanus coccopoma (Darwin, 1854) (Cirripedia: Balanomorpha) and the role of shipping in its translocation

The Titan Acorn barnacle, Megabalanus coccopoma, a native of the tropical eastern Pacific, has become established in the western Atlantic (Brazil and the northern Gulf of Mexico to the Carolinas), northwestern Europe and the western Indian Ocean (Mauritius), and therefore its dispersal capabilities are well known. This study reports its introduction to Japan and confirms its occurrence in Australia. In an attempt to determine the source of this introduction, phylogeographic techniques, involving cytochrome c oxidase I sequences of various widely separate populations of M. rosa and M. volcano, were utilized. No significant genetic differentiation or haplotype patterns between widely separated populations of each of the three species were found. Lack of such differentiation indicates recent geographical isolation and thus negates a null hypothesis predicting that the occurrence of one of more of these species in Australia was natural.

A revision of stalked barnacles (Cirripedia: Thoracica: Scalpellomorpha: Eolepadidae: Neolepadinae) associated with hydrothermalism, including a description of a new genus and species from a volcanic seamount off Papua New Guinea

In describing a new species of pedunculate barnacle that occurs in large numbers in sulphidic seep conditions on a volcanic seamount off Lihir Island, Papua New Guinea, it has been necessary to revise the Neolepadinae and erect two new genera. Capitulum and peduncle characters distinguish the new genera from the species ofNeolepas that occur at hydrothermal vents along the East Pacific Rise. The new genus and species from Lihir Island also differs fromNeolepas osheai described from the Kermadec Ridge, which, together with an undescribed species discovered on the Pacific-Antarctic Ridge, belongs to another new genus. The species discussed are all adapted to feed on fine particles, including bacteria.

Molecular phylogeny, systematics and morphological evolution of the acorn barnacles (Thoracica: Sessilia: Balanomorpha).

The Balanomorpha are the largest group of barnacles and rank among the most diverse, commonly encountered and ecologically important marine crustaceans in the world. Paradoxically, despite their relevance and extensive study for over 150years, their evolutionary relationships are still unresolved. Classical morphological systematics was often based on non-cladistic approaches, while modern phylogenetic studies suffer from severe undersampling of taxa and characters (both molecular and morphological). Here we present a phylogenetic analysis of the familial relationships within the Balanomorpha. We estimate divergence times and examine morphological diversity based on five genes, 156 specimens, 10 fossil calibrations, and six key morphological characters. Two balanomorphan superfamilies, eight families and twelve genera were identified as polyphyletic. Chthamaloids, chionelasmatoid and pachylasmatoids split first from the pedunculated ancestors followed by a clade of tetraclitoids and coronuloids, and most of the balanoids. The Balanomorpha split from the Verrucidae (outgroup) in the Lower Cretaceous (139.6 Mya) with all the main lineages, except Pachylasmatoidea, having emerged by the Paleocene (60.9 Mya). Various degrees of convergence were observed in all the assessed morphological characters except the maxillipeds, which suggests that classical interpretations of balanomorphan morphological evolution need to be revised and reinterpreted.

Australian barnacles (Cirripedia: Thoracica), distributions and biogeographical affinities.

Currently, 279 barnacle species are recognized in Australia waters. The barnacle fauna of tropical Australia exhibits high species diversity (221), with a high incidence of tropical species (87 Indo-west Pacific [IWP], 16 West Pacific and 65 Indo-Malayan), a low species endemicity (8), and 44 cosmopolitan and 1 Australasian species. Conversely, that of temperate Australia shows lower species diversity (129), with a lower incidence of tropical species (26 IWP, 10 West Pacific and 25 Indo-Malayan), higher species endemicity (23), 37 cosmopolitan, 6 Australasian species, and 3 Australasian/Antarctic species. Distributions corroborate the general patterns demonstrated by the shallow-water biota of northern tropical and southern temperate Australian biogeographic provinces. Tropical and temperate provinces grade into each other in a broad overlap zone along both the western and eastern Australian coasts. This overlap zone is essentially a transitional region, with the gradual replacement of a tropical barnacle fauna in the north by a predominantly temperate barnacle fauna in the south. Both western and eastern Australian coasts are bounded by major poleward-flowing warm currents that have considerable influence on the marine flora and fauna, distributing tropical species of many taxa much farther south than could be predicted by latitude. Currently, 16 barnacle species introduced into Australian waters are identified, although this number may increase in the future due to new port developments and increased shipping arrivals.

Barnacles (Crustacea : Cirripedia) from Conic Island Cave, Hong Kong

Two species of barnacles (Cirripedia) have been collected from Conic Island Cave, Hong Kong, at depths of between −11.8 and −18.2 m C.D. These are Armatobalanus quadrivittatus (Darwin) and Tetraclitella pilsbryi (Utinomi). Neither is a cave endemic. Armatobalanus quadrivittatus ranges widely throughout the Indo‐West Pacific and T. pilsbryi is restricted to the Sino‐Japanese region (the East and South China Seas and waters of southern Japan) although both are typical of hypobiotic niches. Armatobalanus quadrivittatus has not hitherto been recorded from Hong Kong and its occurrence here brings the local total of barnacle species to 60.