Microchlamylla gracilis

Microchlamylla gracilis  (Alder & Hancock, 1844)

Microchlamylla gracilis with spawn @ Netherlands 27-03-2017 by Stefan Verheyen

Taxonomy
Class: Gastropoda  Cuvier, 1797
Subclass: Heterobranchia  J.E. Gray, 1840
Clade: Euthyneura  Spengel, 1881
Clade: Nudipleura  Wägele & Willan, 2000
Order: Nudibranchia  Cuvier, 1817
Suborder: Dexiarchia  Schrödl, Wägele & Willan, 2001
Infraorder: Cladobranchia Willan & Morton, 1984
Parvorder: Aeolidida Odhner, 1934
Superfamily: Flabellinoidea  Bergh, 1889
Family: Coryphellidae Bergh, 1889
Genus: Microchlamylla Korshunova, Martynov, Bakken, Evertsen, Fletcher, Mudianta, Saito, Lundin, Schrödl & Picton, 2017
Species: Microchlamylla gracilis (Alder & Hancock, 1844)

Taxonomic note: The classification of the Flabellinidae had remained fairly stable until in 2017 a series of works appeared (Furfaro et al., 2017; Korshunova et al., 2017) that intended to clarify the status of the Flabellinidae family. The main objective of the paper by Furfaro et al. was to molecularly characterize the Mediterranean species while the paper by Korshunova et al. wanted to delve into the phylogenetic relationships between various members of the Flabellinidae family and the other families of aeolidaceans.
Both works were based on the combination of molecular and morphological techniques and, in fact, do not offer very different results, but differ on the size and origin of the studied samples and, mainly, on the interpretation of the results. After the appearance of the paper by Furfaro et al., many Mediterranean species of the genera Calmella, Flabellina and Piseinotecus were grouped under the common genusFlabellina, but had certain problems with some species that did not fit well with the proposed classification (e.g,Flabellina babai) , discovered that the Mediterranean and Atlantic populations ofFlabellina ischitana correspond to two different cryptic species, and noted the problems of the cryptic group formed by Calmella cavolini / Flabellina confusa / Piseinotecus gaditanus, indicating the need for further studies to clarify their status.
Curiously, these studies were being carried out practically in parallel by the group of Korshunova et al. but on a much wider sample of species that included specimens from the Arctic, North Atlantic, Pacific and Indian Oceans. This second paper confirms the polyphily of the family Flabellinidae, but the interpretation of these results becomes a real revolution for the taxonomy of the aeolidaceans, especially for the family Flabellinidae.
Both papers show that there are two well differentiated clades (groups) in the Flabellinidae: species like Coryphella pedata and similars, with cerata that come directly from the back, and species like Flabellina affinis and similars, with cerata of each group coming from a stalk or pod. Although Furfaro et al. consider the species of both clades belonging to the genusFlabellina within the family Flabellinidae, Korshunova et al. distinguishes two families: Coryphellidae and Flabellinidae sensu stricto, also creating many different genera in these families to include the species they study. Its taxonomic proposal, curiously, solves the problems found by Furfaro et al.
In a way, both papers complement to each other, although in the paper by Korshunova et al. it is evident the lack of studies on tropical flabellinid species and those from southern America and Africa, so the subject has not been settled. The proposal to create new genera to collect small groups of species, instead of multispecific genera, seems to be the trend in some of the phylogenetic works of recent years. We hope to see new papers expanding the knowledge on the aeolidaceans soon. A detailed discussion of this exciting controversy can be found at (https://opistobranquis.info/en/flabellinidae/).

Synonyms

  • Coryphella gracilis (Alder & Hancock, 1844)
  • Coryphella rufibranchialis var. clavigera Odhner, 1929
  • Eolis gracilis Alder & Hancock, 1844 (original)
  • Eolis smaragdina Alder & Hancock, 1851
  • Flabellina gracilis (Alder & Hancock, 1844)

Description

Biology

Etymology

  • Microchlamylla. After “micro” and “chlamylla“; in reference to the unusually long vas deferens
    of this genus typical for the genus Chlamylla of the family Paracoryphellidae, but
    smaller body size and discontinuous notal edge, common in the family Coryphellidae.
  • Gracilis. From Latin “gracilis”, thin, tiny.

Distribution

Known georeferenced records of the species: Microchlamylla gracilis
Sources:
: OBIS
: GROC 2010-2011
: Enric Madrenas
: João Pedro Silva
: Bernard Picton
: GBIF.ORG
: OPK
: VIMAR
: Manuel Ballesteros.
: M@re Nostrum
: Altres fonts
: Marine Regions

References for the species: Microchlamylla gracilis

    Cantabria: Hidalgo (1916, as Coryphella).

    General: Bergh, 1875:635; Brown & Picton, 1979:19; Colgan, 1914:186; Dekker, 1989:101; Eliot, 1906c:359; Farran, 1909:7; Garstang, 1890:440; Hayward, Wigham, & Yonow, 1990:724; Hoffmann, 1926:20; Kuzirian, 1979:241; Lemche, 1936:138; 1938:26; Nordsieck, 1972:73; Picton, 1978:88; Picton & Morrow, 1994:94[P]; Pruvot-Fol, 1954b:424; Roginskaya, 1987d:189; Swennen, 1987:40; Thompson, 1988:250; Thompson & Brown, 1984:109[P] as Coryphella gracilis

    Sources: Cervera et al., 2004, Ballesteros, 2007 & 2016, McDonald, 2006 and other sources.

Abundance

    Western Mediterranean:
    Eastern Mediterranean:
    Atlantic Ocean:
This chart displays the observation probability for Microchlamylla gracilis based on our own records.

More pictures

Bibliography

Further reading

Cite this article as:

Ballesteros, Manuel, Enric Madrenas, Miquel Pontes (2012-2018) "Microchlamylla gracilis" in OPK-Opistobranquis, Published: 15/10/2014, Accessed: 19/01/2018 at (https://opistobranquis.info/en/Ba6Nu)

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