Full Length Article
Redescription and notes on the New Zealand ladybird species Hoangus venustus (Pascoe, 1875) (Coleoptera: Coccinellidae)

https://doi.org/10.1016/j.aspen.2018.12.010Get rights and content

Highlights

  • The New Zealand ladybird beetle genus Hoangus is redescribed.

  • Hoangus is transferred from the tribe Cranophorini to Coccidulini.

  • The most likely closest relatives from the genera Cranoryssus and Orynipus are distributed in Southern South America.

Abstract

A detailed morphological re-description of the New Zealand endemic monotypic genus Hoangus Ukrainsky, 2006 is given, along with illustrations of genitalia and key diagnostic characters. The genus is transferred from Cranophorini to Coccidulini based on several morphological characters: its more or less parallel-sided terminal labial palpomere, maxillae with a row of sclerotized spines on the lacinia, unmodified scape, and elongated mesoventrite, rendering the former tribe monotypic. Limited natural history data indicates that Hoangus venustus (Pascoe) maybe a specialist predator on stenorrhynchan hemipterans associated with flax.

Introduction

The taxonomy of native ladybird beetles of New Zealand is poorly studied. All but a handful of species were described in the 1800's with a majority of the species described by Thomas Broun in the genus Scymnus Kugelann and transferred to the genus Rhyzobius Stephens in Maddison's Coleoptera checklist (2010). Later in the 19th century numerous species of ladybird beetles were introduced as biological control agents or accidentally introduced. Presently, 44 species of coccinellids occur in New Zealand, among them only 25 are native (Maddison, 2010).

In general, most ladybird beetles native species are rather dull coloured, but one of the few strikingly coloured and most extraordinary species is Hoangus venustus described by Pascoe (1875) under the original combination Cranophorus venustus. Based on the prolonged pronotum covering the head from above, Pascoe (l.c.) classified this New Zealand species together with the South African C. notatulus Mulsant and C. quadrinotatus Mulsant in the genus Cranophorus Mulsant, 1850. Nonetheless, Pascoe (1875) also expressed some doubts about its placement and wrote “but a minuter examination might show structural peculiarities requiring its generic separation from the Cape species which have certainly a somewhat different aspects”. Subsequently, Weise described the genus Cassiculus Weise, 1895 to accommodate Cranophorus venustus, and noticed that the hairs on pronotum are directed forwards instead of backwards as in Cranophorus. Thereafter, C. venustus draw little attention by researchers until Ukrainsky (2006) provided a new replacement name Hoangus Ukrainsky, 2006 for Cassiculus as it was preoccupied by the bird genus Cassiculus Swainson, 1827.

Higher-level classification of the genus Hoangus and its supposed relatives was rather stable. Mulsant (1850) described the genera Cranophorus (South Africa) and Oryssomus (South America) that possess the same peculiar pronotal form, and placed them together in his “branch” Cranophoraires: That classification was followed by Chapuis (1876, Cranophorites). Subsequently Broun (1883) described Holopsis from New Zealand and believed that it also belongs to this group. Weise (1895) in his description of Cassiculus stated that it is close to Cranophorus. In 1899, Casey newly defined a tribe Cranophorini Mulsant, 1850 to accommodate three genera Cranophorus, Oryssomus and his new genus Nipus Casey. Brèthes described the genera Cranoryssus Brèthes (1923) and Orynipus Brèthes (1925), both from Chile, placing them also in the Cranophorini. Korschefsky (1931) in his catalogue listed all of the above genera in the tribe Cranophorini as well as Cleidostethus Arrow, 1929. Subsequently Cleidostethus and Holopsis were transferred to the family Corylophidae (Crowson, 1955; Bowestead et al., 2001). Gordon (1974) noticed that “the remaining genera are a heterogenous assemblage of mostly unrelated elements which have been placed together only because they have the head concealed by the pronotum”. He transferred Nipus to the tribe Microweiseini (Gordon, 1970, Gordon, 1977), Oryssomus to the tribe Oryssomini (Gordon, 1974), Cranoryssus and Orynipus to Coccidulini (Gordon, 1994), leaving Cranophorus and Hoangus (as Cassiculus) in the tribe Cranophorini. Traditionally, the tribes Coccidulini, Cranophorini and Oryssomini were placed in the former subfamily Coccidulinae (Fürsch, 1996; Nedvěd and Kovář, 2012). The relationship between Cranophorus and Hoangus has never been assessed. Gordon (1994) proposed to transfer Hoangus (as Cassiculus) to Scymninae, but this placement was not followed by subsequent authors (e.g., Fürsch, 1996; Nedvěd and Kovář, 2012).

In the past few years the classification of the family Coccinellidae has changed significantly. Analyses of morphological and molecular data redefined the higher-level classification by creating a 2-subfamily system of Coccinellinae and Microweiseinae (Ślipiński, 2007; Seago et al., 2011; Escalona and Ślipiński, 2012; Szawaryn et al., 2015; Tomaszewska and Szawaryn, 2016; Escalona et al., 2017) leaving many of the coccinelline tribes in flux and poorly defined, including the former subfamily Coccidulinae which may be the most problematic and includes the majority of New Zealand species. The purpose of this study is to redescribe the genus Hoangus, assess its tribal placement, and record its biology.

Section snippets

Materials and methods

Specimens used in this study are deposited in Auckland War Memorial Museum (AMNZ), The Natural History Museum, London, United Kingdom (BMNH); Canterbury Museum, Christchurch, New Zealand (CMNZ); New Zealand Arthropod Collection, Muséum national d'Histoire naturelle, Paris, France (MNHN); New Zealand Arthropod Collection, Auckland, New Zealand (NZAC). Two-letter area codes were used for specimen localities following Crosby et al. (1998).

Measurements were made using an ocular micrometer attached

Discussion

Early researchers (Mulsant, 1850; Chapuis, 1876) placed ladybirds with the pronotum covering the head in the tribe Cranophorini. More recent taxonomic studies indicate that this character evolved independently in the family and particularly several Southern Hemisphere ladybirds, mostly all but two formerly included in the subfamily Coccidulinae: Cranophorini (Cranoporus [South Africa]), Oryssomini (Oryssomus, Pseudoryssomus Gordon, Gordonoryssomus Almeida et Lima, Anisorhyzobius Hofmann,

Conflict of interest to declare

None.

Acknowledgments

We thank Guillermo Gonzalez (Santiago, Chile) for his help with South American taxa and providing habitus photos of Cranoryssus, Neoryssomus and Orynipus. We thank Max Barclay, Micheal Geiser, and Keita Matsumoto (BMNH) for assistance with specimens and the latter for images of the Pascoe type. We thank Romain Nattier for his assistance and help in finding additional specimens in MNHN. The following are also thanked for supplying locality data: Ruby Moore (AMNZ); Cor Vink (CMNZ), John Nunn

References (37)

  • A.E. Seago et al.

    Phylogeny, classification and evolution of ladybird beetles (Coleoptera: Coccinellidae) based on simultaneous analysis of molecular and morphological data

    Mol. Phylogenet. Evol.

    (2011)
  • L.M. Almeida et al.

    Synopsis of Oryssomini Gordon (Coleoptera: Coccinellidae) from the Neotropical region with new species of Oryssomus Mulsant, Pseudoryssomus Gordon and Gordonoryssomus Almeida & Lima

    Zootaxa

    (2014)
  • G.A. Arrow

    A remarkable new genus of coccinellid Coleoptera

    Ann. Mag. Nat. Hist. Ser.

    (1929)
  • S. Bowestead et al.

    The genus Cleidostethus Arrow 1929 reappraisal and transfer from Coccinellidae to Corylophidae (Coleoptera: Cucujoidea)

    Ann Zool

    (2001)
  • J. Brèthes

    Catalogue synonymique des Coccinellides du Chili

    Rev. Chil. Hist. Nat.

    (1923)
  • J. Brèthes

    Sur une collection de Coccinellides (et un Phalacridae) du British Museum

    Anal. Museo Nacional Buenos Aires

    (1925)
  • T. Broun

    Manual of the New Zealand Coleoptera. Part 1

    (1880)
  • T. Broun

    Revision of the New Zealand Cossonidae, with descriptions of new species [Continued.]

    N. Z. J. Sci. (Dunedin)

    (1883)
  • T.L. Casey

    A revision of the American Coccinellidae

    J. N. Y. Entomol. Soc.

    (1899)
  • M.F. Chapuis

    Famille des Erotyliens, des Endomychides et des Coccinellides

  • T.K. Crosby et al.

    Area codes for recording specimen localities in New Zealand subregion

    N. Z. J. Zool.

    (1998)
  • R.A. Crowson

    The Natural Classification of the Families of Coleoptera

    (1955)
  • H. Escalona et al.

    Generic revision and phylogeny of Microweiseinae (Coleoptera: Coccinellidae)

    Syst. Entomol.

    (2012)
  • H.E. Escalona et al.

    Molecular phylogeny reveals food plasticity in the evolution of true ladybird beetles (Coleoptera: Coccinellidae: Coccinellini)

    BMC Evol. Biol.

    (2017)
  • H. Fürsch

    Taxonomy of Coccinellids

    Coccinella

    (1996)
  • H. Fürsch

    Die Gattung Cranophorus Mulsant

    Mitteilungen der Münchner Entomologischen Gesellschaft

    (1998)
  • M. García Morales et al.

    ScaleNet: a literature-based model of scale insect biology and systematics

    Database

    (2016)
  • R.D. Gordon

    A review of the genus Nipus Casey (Coleoptera: Coccinellidae)

    Coleopterist Bull.

    (1970)
  • Cited by (0)

    View full text