Helictopleurus clouei ( Harold, 1869 )

Rossini, Michele, Montanaro, Giulio, Montreuil, Olivier & Tarasov, Sergei, 2024, Towards computable taxonomic knowledge: Leveraging nanopublications for sharing new synonyms in the Madagascan genus Helictopleurus (Coleoptera, Scarabaeinae), Biodiversity Data Journal 12, pp. e 120304-e 120304 : e120304-

Helictopleurus clouei ( Harold, 1869)

Oniticellus clouei Harold 1869: 68 ; Harold 1880: 155; Fairmaire 1895: 13; Fairmaire 1898: 471;

Helictopleurus clouei : d’Orbigny 1915: 428 (new combination) (Figs 2 e , 3 b ); Lebis 1960: 111; Gillet and Boucomont 1927: 110; Paulian 1986: 104; Montreuil 2005 a: 134;

Oniticellus gibbicollis Fairmaire 1895: 16 ;

Helictopleurus gibbicollis d’Orbigny 1915: 433 (new combination) (syn. nov.) (Figs 2 f , 3 b ); Gillet and Boucomont 1927: 110; Lebis 1960: 119; Paulian 1986: 105; Montreuil 2005 a: 134 ;

Materials

Type status: Holotype. Occurrence: individualCount: 1; sex: male; lifeStage: adult; preparations: dry; disposition: in collection; otherCatalogNumbers: MALP 0613; occurrenceID: 0D6427C9-F941-5E24-9379-940C5792B676; Taxon: scientificName: Helictopleurus clouei ( Harold, 1869) ; namePublishedIn: Harold, E. von 1869. Coprophage Lamellicornien mit besonderer Berücksichtigung der Pariser Sammlungen, 5: 46–70; class: Insecta; order: Coleoptera ; family: Scarabaeidae ; genus: Helictopleurus ; specificEpithet: clouei ; taxonRank: species; scientificNameAuthorship: Harold, 1869; nomenclaturalCode: ICZN; taxonomicStatus: valid; Location: continent: Africa; country: Madagascar; verbatimLocality: Madagascar; Identification: identifiedBy: E. von Harold; Record Level: institutionCode: MNHN; basisOfRecord: PreservedSpecimen

Type status: Syntype. Occurrence: individualCount: 1; sex: male; lifeStage: adult; preparations: dry; disposition: in collection; otherCatalogNumbers: MALP 0649; occurrenceID: B95EA3D8-F28F-59EF-B526-3B1B5EA5A178; Taxon: scientificName: Helictopleurus gibbicollis ( Fairmaire, 1895) ; namePublishedIn: Fairmaire, L. M. H. 1895. Descriptions de quelques Coléoptères de Madagascar. Annales de la Société Entomologique de Belgique, 39: 8–40; class: Insecta; order: Coleoptera ; family: Scarabaeidae ; genus: Helictopleurus ; specificEpithet: gibbicollis ; taxonRank: species; scientificNameAuthorship: Fairmaire, 1895; nomenclaturalCode: ICZN; taxonomicStatus: subjective synonym; Location: continent: Africa; country: Madagascar; verbatimLocality: Diego-Suarez; Identification: identifiedBy: Fairmaire, L. M. H.; Event: year: 1893; Record Level: institutionCode: MNHN; basisOfRecord: PreservedSpecimen

Diagnosis

Helictopleurus clouei is distinguished from other members of the H. quadripunctatus group by the pronotum metallic-green and shining (opaque, dark green to bluish in the other species); elytra orange to dark brown (black with a medial yellow stripe in H. perrieri ), with poorly-defined dark spots at the base and apex (spots more distinct in H. quadripunctatus ). Harold (1869) suggests that H. clouei may be related to H. quadripunctatus , but specimens of H. clouei are visibly smaller.

Distribution

This species occurs in northern Madagascar and is relatively common in open habitat (Fig. 3 b ).

Taxon discussion

According to Harold (1869), the original description of H. clouei was allegedly based on a single female specimen without exact type locality. In the present study, the examination of this unique syntype allowed us to confirm that it is actually a male. This species is today assigned to the quadripunctatus group, together with H. quadripunctatus (Olivier, 1789) , H. perrieri ( Fairmaire, 1898) and H. gibbicollis ( Fairmaire, 1895) ( Lebis 1960, Montreuil 2005 a).

Amongst the numerous Helictopleurus authored by L. M. H. Fairmaire (1820–1906), in 1895, he described H. gibbicollis from a single male specimen collected by C. A. Alluaud (1861–1949) in Diego Suarez ( Fairmaire 1895). This species was originally assigned to the semivirens group ( Lebis 1960) and later moved to the quadripunctatus group ( Montreuil 2005 a). Despite Fairmaire’s explicit statement about the collecting event, it is still unclear why Lebis (1960) and Paulian (1986) indicate " Mandritsara " as type locality of the species.

Over the years and despite the intense dung beetle surveys carried out in Diego Suarez and surroundings (e. g. Hanski et al. (2007)), H. gibbicollis has never been recollected nor mentioned in any work. This makes the taxonomic identity of this species fairly questionable and in urgent need of validation.

The morphological examination of the syntypes of H. clouei and H. gibbicollis allowed us to establish the latter as a junior subjective synonym of H. clouei ( H. gibbicollis syn. nov.). Probably, the different colour of the elytra of the two specimens (dark brown in the syntype of H. gibbicollis and bright orange in H. clouei ) might have confused former authors, who kept considering H. clouei and H. gibbicollis as distinct species. However, the shape of the cephalic ornaments (carinas and frontal horn) and pronotum, the pronotal tegument, the colour pattern of elytra and the shape of the parameres clearly indicate that the two specimens are conspecific.

This new synonymy reduces the number of species of the quadripunctatus group to three.

Figures

Figure 2 e. Dorsal and frontolateral habitus and labels of the syntype of H. clouei;

Figure 3 b. H. clouei (red arrow indicates the type locality of H. gibbicollis syn. nov.);

Figure 2 f. Dorsal and frontolateral habitus and labels of the syntype of H. gibbicollis.