Symbiotic association between Solanderia secunda (Cnidaria, Hydrozoa, Solanderiidae) and Medioantenna variopinta sp. nov. (Annelida, Polychaeta, Polynoidae) from North Sulawesi (Indonesia)

Abstract

A mimic scale-worm was found associated with the athecate hydroid Solanderia secunda, commonly found on reefs of the NW coast of North Sulawesi, Indonesia. The species resembled Medioantenna clavata Imajima 1997, which was originally described without any reference to a symbiotic mode of life and later reported to be living on a solanderiid hydroid both in Japanese waters. A detailed morphological analysis led us to consider the Indonesian specimens as a new species, namely Medioantenna variopinta sp. nov., which is congeneric with the Japanese species. The new species differs from the type material of M. clavata as it has elytra with one prominent finger-like papilla and all neurochaetae with unidentate tip, instead of an elytral lump and both unidentate and bidentate neurochaetae on segment two. In turn, the Japanese worms associated with Solanderia are here referred to our new species. Two morphological features in M. variopinta sp. nov. are rather unusual among scale-worms. One of them is its extremely high level of bilateral asymmetry and antero-posterior variability in elytral distribution and the other one is its elongated, upwardly directed nephridial papillae. The morphology and geographical distribution of the host together with the known characteristics of the symbiotic association have also been highlighted.

New symbiotic associations involving polynoids (Polychaeta, Polynoidae) from Atlantic waters, with redescriptions of Parahololepidella greeffi (Augener, 1918) and Gorgoniapolynoe caeciliae (Fauvel, 1913)

“…Also, the elytra distribution becomes asymmetrical (within a given worm) and irregular (between worms) from chaetiger 32 or 33 to the end of the body (Table 2). A similar variability was also described for another long bodied species, Medioantenna variopinta (Di Camillo et al, 2011). The shape of elytra may also vary.…”

Peripheral communities of the Eastern Lau Spreading Center and Valu Fa Ridge: community composition, temporal change and comparison to near‐vent communities

“…Polynoid–cnidarian associations are common and have been reported with hydroids (Di Camillo et al . ), gorgonians (Pettibone ), antipatharians (Pettibone ) and even a species of unattached coral (Pettibone ). Pettibone () described an association between a polynoid, Alentiana aurantiaca , and an actinarian anemone, Bolocera tuediae .…”

“…It is not known whether or how either partner benefits from the relationship; however, the Lau polynoids match their hosts' coloration, which is common among polynoids in a trophic symbiosis (Gibbs ; Pettibone ; Martin & Britayev ; Di Camillo et al . ) as well as those thought to associate with hosts for protection from predation (Pettibone ; Martin & Britayev ). The Harmothoinae polynoids that were not seen to associate with anemones tend to have a darker, yellowish color, which did not match the white coloration of the anemones and anemone‐associated polynoids.…”

“…Polynoids are well known for their symbiotic associations and in fact, more than half (55%) of all known commensal polychaetes are polynoids (Martin & Britayev 1998). Polynoid-cnidarian associations are common and have been reported with hydroids (Di Camillo et al 2010), gorgonians (Pettibone 1991a), antipatharians (Pettibone 1991b) and even a species of unattached coral (Pettibone 1989). Pettibone (1963) described an association between a polynoid, Alentiana aurantiaca, and an actinarian anemone, Bolocera tuediae.…”

Associations between the White Sea colonial hydroidDynamena pumilaand microorganisms

“…That is the first example of such information on the biology of hydroids from the high latitude seas. The works on the associations of hydroids and epibiotic community are not numerous on the whole (Round et al , 1961; Bavestrello et al , 1996; Siqueiros-Beltrones et al , 2001; Di Camillo et al , 2006, 2010; Stabili et al , 2008). Despite the high species number (Di Camillo et al , 2008) hydroid biomass is low in tropical and subtropical regions and therefore hydroids do not play a significant role in ecosystem functioning.…”