Thursday, August 8, 2019

[Mollusca • 2019] Moridilla jobeli • A New Moridilla Species (Mollusca: Nudibranchia: Aeolidioidea) from North Sulawesi, Indonesia —based on MicroCT, Histological and Molecular Analyses



Moridilla jobeli Schillo & Wägele

in Schillo, Wipfler, Undap, Papu, Böhringer, et al., 2019. 

Abstract
We describe a new species, Moridilla jobeli sp. nov., belonging to the marine heterobranch group Aeolidioidea. Up to now, it is only recorded from Bunaken National Park, North Sulawesi, Indonesia. A combination of histological, computer tomographic and scanning electron microscopic methods was applied in order to describe and illustrate the anatomy of Moridilla jobeli sp. nov. in detail. Furthermore, we conducted molecular analyses which include available partial COI and 16S rRNA sequences, as well as the nuclear gene Histone 3 (H3) of Facelinidae and Aeolidiidae. NeighborNet analyses, species delimitation tests and phylogenetic reconstruction methods show the distinctiveness of the new species from the type species Moridilla brockii Bergh, 1888 and the two recently described species Moridilla fifo Carmona & Wilson, 2018 and Moridilla hermanita Carmona & Wilson, 2018, as well as the monophyly of the genus. A phylogenetic analysis of the Facelinidae and Aeolidiidae does not result in a resolved tree, therefore relationship of former assumed closely related genera, Noumeaella Risbec, 1937 and Palisa Edmunds, 1964, cannot be discussed in detail.

Keywords: Mollusca, Facelinidae, Aeolidiidae, Noumeaella, Palisa, systematics, species delimitation, integrative taxonomy

Figure 2. Moridilla jobeli sp. nov.: Living animals.
 (A) SRU2015/01/Nosp2-15Bu-2 on Caulerpa racemosa, with closeup of cerata. (B) Paratype SRU20190001.
(C) Paratype SRU20190001ventral view, SRU2015/01/Nosp2-15Bu-2 lateral view on original substrate Caulerpa racemosa. (D) SRU2016/02/Nosp2-16Bu-1 in situ, with close-up of cerata.
(E) SRU2016/02/ Nosp2-16Bu-5 crawling on sponge. (F) Holotype MZB.Gst.21.592 in situ on sponge.

Systematics 
Nudibranchia Cuvier, 1817 
Cladobranchia Willan & Morton, 1984 
Family Facelinidae Bergh, 1889 

Genus Moridilla Bergh, 1888 
Type species. Moridilla brockii Bergh, 1888 

Diagnosis. The genus Moridilla is characterized by the following features: Body elongate, slender, tapering at posterior end of foot. Foot narrow; foot corners tentacular elongated. Rhinophores side by side, papillate. Tentacles elongate. Anterior cerata in slanted rows with innermost dorsal cerata unique in shape, significantly elongated, in coiled position, differently coloured; get fully extended in length and waved about forcefully when animal feels threatened. Jaw medium sized, masticatory border strong, slightly curved with single row of denticles. Radula uniseriate. Penis unarmed. Semi-serial receptaculum seminis (Bergh 1888; Edmunds 1970). 

Moridilla jobeli sp. nov.: Living animals. (D) SRU2016/02/Nosp2-16Bu-1 in situ, with close-up of cerata.  (F) Holotype MZB.Gst.21.592 in situ on sponge.


Moridilla jobeli sp. nov. Schillo & Wägele

Type locality and live observation. Only recorded from several localities in Bunaken National Park, North Sulawesi, Indonesia (Figure 1, Table 1). When disturbed, animals started to swim with lateral movements to avoid disturbance and inner cerata are forcefully extended, as typical for the genus. 

Etymology. This species is dedicated to Jobel Dialao, Bunaken Island, whose outstanding skills and dedication in finding and collecting marine heterobranchs are honoured here. 


Dorothee Schillo, Benjamin Wipfler, Nani Undap, Adelfia Papu, Nils Böhringer, Jan-hendrik Eisenbarth, Fontje Kaligis, Robert Bara, Till F. Schäberle, Gabriele M. König and Heike Wägele. 2019. Description of A New Moridilla Species from North Sulawesi, Indonesia (Mollusca: Nudibranchia: Aeolidioidea)—based on MicroCT, Histological and Molecular Analyses. Zootaxa. 4652(2); 265–295. DOI: 10.11646/zootaxa.4652.2.3

Abstrak: Kami mendeskripsikan spesies baru, Moridilla jobeli sp. nov., dari taxon Aeolidioidea, dikumpulkan di Sulawesi Utara, Indonesia, dengan menerapkan metode histologis, tomografi komputer dan metode scanning electron microscopic, untuk menganalisis anatominya secara rinci. Selanjutnya analisis molekuler dilakukan dengan memasukkan sekuens yang tersedia dari COI parsial, 16S rRNA, parsial dan Histone 3 (H3) dari Facelinidae dan Aeolidiidae. Analisis NeighborNet, tes delimitasi spesies dan metode rekonstruksi filogenetik menunjukkan kekhasan spesies baru dari jenis spesies Moridilla brockii Bergh, 1888 dan dua spesies Moridilla fifo Carmona & Wilson, 2018 dan Moridilla hermanita Carmona & Wilson, 2018, yang baru-baru ini dijelaskan, serta monophyly dari genus. Analisis filogenetik dari Facelinidae dan Aeolidiidae tidak menghasilkan pohon yang terselesaikan, oleh karena itu hubungan keduanya yang diasumsikan terkait erat dengan genera Noumeaella Risbec, 1937 dan Palisa Edmunds, 1964, tidak dapat dibahas secara rinci.