FNZ 3 - Anthribidae (Insecta: Coleoptera) - Relationships
Holloway, BA 1982. Anthribidae (Insecta: Coleoptera). Fauna of New Zealand 3, 272 pages.
(
ISSN 0111-5383 (print),
;
no.
03.
ISBN 0-477-06703-4 (print),
).
Published 23 Dec 1982
ZooBank: http://zoobank.org/References/AC1DC576-5021-40DE-9BD7-0F7C591C6521
Faunal Composition and Relationships
The world fauna of Anthribidae is divided very unevenly among three subfamilies (Crowson 1955): Bruchelinae with about 50 species; Choraginae with about 400 species; and Anthribinae with the remainder. New Zealand, with 2 adventives and 58 endemic species, has about two percent of the present known world fauna. By comparison, Chile has only 13 species (Wolfrum 1929, 1953), Australia has 57 (Britton 1970), America north of Mexico has 87 (Valentine 1960), and Japan has 99, of which about 68 are endemic (Morimoto 1978, 1979, 1980).
All the New Zealand species are small, ranging in length (excluding the rostrum) from 0.8 mm in Micranthribus atomus to about 7 mm in Cacephatus aucklandicus. Exotic anthribids range in length from about 1 mm in a species of Cisanthribus from New Caledonia to 35 mm in males of Deuterocrates griseopictus from Brazzaville. Large specimens of D. griseopictus have antennae measuring as much as 90 mm in length. Most New Zealand anthribids have only moderately long antennae. A few of the New Zealand species have greenish integument, but most are brown or black and rather drab-looking - they lack the striking colour patterns that are a feature of many tropical and subtropical anthribids.
The subfamily Bruchelinae is not represented in New Zealand; the endemic species of Anthribidae in New Zealand are divided between Anthribinae, with 42 species, and Choraginae with 16. The endemic Anthribinae belong in 22 genera, which can be grouped in the following 3 major categories according to overall body form, length and insertion of the antennae, and shape and position of the eyes.
- Stout-bodied forms with a conspicuous rostrum, laterally inserted antennae which are shorter than the body, and lateral, widely spaced, entire or barely emarginate eyes: Cacephatus, Caliobius, Garyus, Gynarchaeus, Helmoreus (eyes slightly dorsal), Hoplorhaphus, Lichenobius, Lophus, Pleosporius, Sharpius, Xenanthribus.
- Stout-bodied forms with a rather inconspicuous rostrum, dorsally or dorsolaterally inserted antennae which are shorter than the body, and lateral, widely spaced, notched to quite deeply emarginate eyes: Dasyanthribus, Etnalis, Eugonissus, Isanthribus.
- Somewhat fragile forms (except if flightless) with an inconspicuous rostrum (except in males of sexually dimorphic species), dorsally or dorsolaterally inserted antennae which usually are longer than the body, and eyes that are either notched and widely spaced or deeply emarginate and more closely approximated: Androporus, Arecopais, Cerius, Hoherius, Lawsonia, Phymatus, Tribasileus.
Two groups of Anthribinae, very characteristic of the tropics, are not represented in New Zealand.
- Compact-bodied forms with a conspicuous rostrum, laterally inserted, short, and usually slender antennae, and large, very finely facetted, entire, closely approximated, dorsal eyes. Genera such as Acorynus, Litocerus, Nessiodocus, and Tropideres which are included in this category occur in tropical areas of the Pacific, and may extend their range through Malaysia to Japan and other parts of Asia.
- Elongate, depressed forms with a conspicuous rostrum, dorsolaterally inserted antennae which usually are stout and very much longer than the body, and large, finely facetted, entire, lateral eyes, Typical genera in this category are Cerambyrhynchus from Fiji and Samoa, Deuterocrates from equatorial Africa, and Ptychoderes from Central America and Brazil.
Eleven genera of New Zealand Anthribinae are endemic and not closely related to one another nor, apparently, to anthribines elsewhere. For the present, at least, they must be regarded as part of the archaic (endemic) element of the New Zealand biota. Eight of these genera - Arecopais, Caliobius, Eugonissus, Garyus, Gynarchaeus, Pleosporius, Tribasileus, and Xenanthribus are monotypic. The other three - Cerius, Etnalis, and Phymatus - have two or three species each. Gynarchaeus ornatus occupies a special position within the family as the only known species in which the hemisternites are of the curculionid type, i.e., have a large apical stylus.
Eight genera of New Zealand Anthribinae are either shared with the region extending northwards from New Caledonia to Malaysia or have affinities with genera occurring in that area, as follows. Androporus has one species in New Zealand and an undescribed species in New Caledonia; Dasyanthribus has a vestigial-winged New Zealand species and an apterous New Caledonian species; Helmoreus has one New Zealand and one New Caledonian species and is also related to Plintheria in New Guinea; Hoherius resembles in some of its features Proscoporhinus from New Caledonia; Hoplorhaphus has affinities with Eczesaris from New Guinea and Malaysia; Lawsonia has one New Zealand species and probably a New Caledonian species; and Lophus shares many of its characters with Perroudius (formerly Tetragonopterus) from New Caledonia.
Only two anthribine genera (apart from the adventive genus Euciodes, which arrived in New Zealand within the last 80 years) can be linked with the Australian fauna. These are Cacephatus, which has six species (including a flightless subantarctic one) in the New Zealand subregion, one species in south-eastern Australia, and an undescribed species on each of Lord Howe and Norfolk islands; and Lichenobius, with a flightless species on each of the Bounty, Snares/Stewart, and Chatham islands which may be distantly related to Xynotropis from Tasmania.
The remaining anthribine genus, Sharpius, has five species, including two that are flightless; it seems to be most closely related to Allandrus, particularly the North American and Japanese species of this genus.
The 16 endemic species of Choraginae belong in four genera which can be grouped as follows on external characters.
- Black, rather parallel-sided forms with sexually dimorphic mandibles and very slender antennae: Notochoragus.
- Black or brown, somewhat ovate forms with similar mandibles in the two sexes and with somewhat robust antennae: Dysnocryptus, Liromus, Micranthribus.
These two categories also seem to encompass the world fauna of Choraginae.
Dysnocryptus, with nine apterous species is the only choragine genus that can be considered to belong to the archaic New Zealand element. Liromus, represented in New Zealand by a single species, possibly occurs in New Caledonia also. Micranthribus has a vestigial-winged New Zealand species and one that is fully winged in New Caledonia. Notochoragus, with five endemic species of which two are flightless, has affinities with Choragus and Melanopsacus. Choragus is an essentially Northern Hemisphere genus that occurs in Europe, North America, and Asia, and Melanopsacus has a range extending from Fiji and Queensland to Japan.
The absence of any relationships between New Zealand and Chilean species can be explained partly by the impoverished and apparently recent nature of the Chilean anthribid fauna. Of the four genera that contain the 13 endemic Chilean species only Sistellorhynchus, with two species, is endemic. The other three - Corrhecerus, Hylotribus, and Ormiscus - are shared with the Neotropical region to the north.
Altogether 27 species, or about 47 percent of the endemic New Zealand Anthribidae, are either apterous or vestigial-winged. Fifteen of these are distributed among the anthribine genera Cacephatus, Caliobius, Cerius, Dasyanthribus, Euyonissus, Isanthribus, Lichenohius, Lophus, Sharpius Tribasileus, and Xenanthribus; the remaining 12 are choragines belonging to Dysnocryptus, Micranthribus, and Notochoragus. The single species of Eugonissus is unusual, and perhaps unique, among Anthribidae because it has fully winged and vestigial-winged forms in both sexes. In a worldwide context the degree of flightlessness seems high, but it does not compare with that recorded by Basilewsky (1972) for the Anthribidae of the South Atlantic island of St Helena, where 24 of the 27 species are apterous. Apparently all the Japanese anthribids are fully winged (Morimoto 1978, 1979, 1980).
The two adventive species of Anthribidae in New Zealand must have been transported in the late nineteenth and early twentieth century on ships from Australia. Euciodes suturalis, a small anthribine whose larvae live in grass stems, is known to have been established in Hawke's Bay by 1924 (Kuschel 1972), and the choragine Araecerus palmaris, which could have been transported either in various mummified fruits or on acacia stems, was first noticed in Wellington in the summer of 1894-95 (Kirk 1895).