Research Article |
Corresponding author: Steven W. Lingafelter ( elaphidion@gmail.com ) Academic editor: Alexander Konstantinov
© 2015 Hilda Waqa-Sakiti, Linton Winder, Steven W. Lingafelter.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Waqa-Sakiti H, Winder L, Lingafelter SW (2015) Review of the genus Ceresium Newman, 1842 (Coleoptera, Cerambycidae) in Fiji. ZooKeys 532: 15-53. https://doi.org/10.3897/zookeys.532.6070
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A taxonomic review of the genus Ceresium (Coleoptera: Cerambycidae) found within the Fiji Islands is presented. A total of 17 species is treated. Full morphological descriptions and comparative images of each species are included, along with a dichotomous key for their identification.
Longhorned beetles, endemic species, taxonomy
Several widespread Cerambycidae genera exist within the Fiji Islands. Among these, the genus Ceresium Newman (Cerambycidae: Cerambycinae: Callidiopini) is known to be represented on most oceanic islands by one or two widespread species, with additional local species restricted to either a single island or an island group (
The Fijian Ceresium species have received little attention since their initial description. A taxonomic study on the Cerambycidae of the Fiji Islands by
Introduction to the Subfamily Cerambycinae; Tribe Callidiopini; Genus Ceresium. The subfamily Cerambycinae has 121 tribes attributed to it globally (
The genus Ceresium is the most speciose in the tribe, comprising 136 species and subspecies globally (
Biology and ecology of the genus Ceresium. Little has been published on the biology and ecology of Ceresium.
The habits of adult Ceresium are virtually unknown. A study on the species C. pachymerum Pascoe in Papua New Guinea by
Distribution of Ceresium in Fiji. Members of the genus in Fiji are known from the islands of Viti Levu, Vanua Levu, Taveuni, Ovalau, Gau, Koro, Kadavu and the Lau group (
Sources and deposition of material. Holotypes of the species recorded for Fiji and described by
Where possible, redescriptions were based on examination of holotype specimens. Occasionally, it was necessary to examine photographs of types or original literature as supplemental references—the latter especially if the holotypes or lectotypes could not be found and presumed lost.
Species description procedure. Species descriptions were made using a standard template for each of the 17 species of Ceresium. Much of the descriptions of each taxon were updated, but, the original text was retained whenever possible when reviewing each species. Observations include detailed descriptions for the head region (vertex and occiput, antennae, frons and frontoclypeal margin; Figure
Original descriptions were also adapted to include detailed high resolution color photographs of each specimen. Photographs of museum voucher specimens were taken using a Leica MZApo stereomicroscope. Extended focus images were taken using a JVC digital camera KY-F70 and Archimed software (Microvision Instruments). Detailed photographs taken for each species included: a) dorsal habitus, b) head region, c) pronotal region and d) ventral region. A key was then developed to provide a means to distinguish individual species.
Ceresium decorum:
Based on the holotype specimen (
Pronotum broadly arcuate, widest across middle, and almost as wide as long. Pronotum with glabrous median vertical line, glabrous patch on either basal sides of median line. Pronotum with sparse punctures and sparsely scattered pubescence elsewhere (Fig.
Venter of abdomen and thorax with sparse translucent to pale, ochraceous pubescence throughout. Length of abdomen 4.38 mm. Prosternal process very narrow, gradually declivous, weakly notched and expanded at apex, approximately 1/8 width of procoxa. Procoxal cavities widely open posteriorly. Mesocoxae closed laterally to mesepimeron. Mesosternum not produced vertically, without anterior tubercle or sulcus; with weak but acute lateral projections into mesocoxae (Fig.
This species is most similar to C. promissum Dillon & Dillon based on the key characters. It is distinguished from that species by having the mesosternal process basal notch angled (parallel-sided in C. promissum) and the pronotum having a narrow, glabrous, longitudinal line centrally located (restricted to posterior half in C. promissum). This species is endemic to Fiji and known only from Moala, Viti Levu, and Lau Islands. It has been collected from rotten logs and dead branches in August and October (
Ceresium epilais:
Based on the holotype specimen (
Pronotum broadly arcuate, widest across middle, and slightly wider than long; apex a little narrower than base. Disc densely punctuate with sparsely scattered pubescence elsewhere (Fig.
Venter of abdomen and thorax with mostly sparse, pale ochraceous pubescence throughout, becoming most dense on episternites. Length of abdomen 3.64 mm. Prosternal process very narrow, barely separating and not extending to posterior margin of procoxae; gradually declivous, not expanded at apex, less than 1/15 width of procoxa. Procoxal cavities widely open posteriorly. Mesocoxae closed laterally to mesepimeron. Mesosternum not produced vertically, without anterior tubercle or sulcus; without lateral projections into mesocoxae (Fig.
Superficially similar in form and color to C. vacillans Dillon & Dillon, it is easily distinguished from that species by having the pronotum more rounded laterally and the elytra lacking glabrous patches. In the key characters, it is most similar to C. lucidum Dillon & Dillon, but is distinguished by having the pronotum widest at middle (widest anteriorly in C. lucidum). This species is endemic to Fiji and known only from a single specimen collected on Viti Levu in June (
Ceresium gracilipes:
Based on photograph of lectotype (
Pronotum feebly elongate; base and apex subequal; sides distinctly arcuate, apical sulcus very broad and shallow; an elongate narrow, median callosity at base; disk slightly less coarsely punctuate than head. Elytra with sides nearly parallel to apical quarter, apices slightly, narrowly rounded, entire disk coarsely, densely rugose. Scutellum broadly rounded, sparsely pubescent with an indistinct, dark macula postmedially. Legs moderate in length, femora moderately clavate with hind femora extending well before elytral apex.
Venter with pubescence unexamined. Prosternum very narrow between procoxae and broadly expanded apically. Mesosternum process wide and strongly expanded at apex, apical margin subtruncate, angle fitting into grooves in mesocoxae; mesocoxae subcontiguous. Fifth sternite attenuate, apical margin strongly emarginate in male; subtruncate in female.
This species is recognized by the relatively narrow, parallel-sided appearance and elytra with an indistinct, postmedial dark macula that extends toward the base. It is distinguished from the similar C. olidum (Fairmaire) by having the elytra more finely punctate and the pronotum less regularly and densely punctate. This species is endemic to Fiji and known from Viti Levu, Taveuni, Ovalau, and the Lau Islands where it has been collected by beating shrubs from August through November (
Ceresium grandipenne:
Based on a specimen housed in
Pronotum quadrate, slightly widest at apical third, and wider than long; not tuberculate; calli absent. Pronotum with moderately dense ochraceous pubescence throughout and moderately dense punctures (Fig.
Venter of abdomen and thorax with moderately dense, ochraceous pubescence at sides, sparse ochraceous pubescence along middle; prosternum sparsely pubescent throughout and on sides. Prosternal process narrow, vertical and acutely declivous, about 1/6 width of procoxa, strongly notched and expanded at apex. Procoxal cavities open posteriorly. Mesocoxae closed laterally to mesepimeron. Mesosternum rather acutely declivous, with small anterior tubercle, and sulcate anteriorly. Mesosternal apex expanded circularly and inserted into mesocoxa (Fig.
There is some inconsistency between the original description (
Hesperophanes guttaticollis:
Ceresium guttaticolle yapense: Gressitt 1956: 86, Micronesia: Yap Islands, holotype (
Based on the holotype (
Pronotum broadly arcuate, widest across middle and slightly wider than long; small tubercles at sides located at middle of sides and anterolaterally. Pronotum with two dense yellow patches of pubescence on either side of pronotum almost subequal in size. Pronotum with sparse punctures and sparsely scattered pubescence elsewhere (Fig.
Venter of abdomen and thorax with moderately dense, ochraceous pubescence throughout becoming less abundant towards 5th ventrite. Prosternal process broad, vertical and acutely declivous, approximately 1/5 width of procoxa, weakly notched and not expanded at apex. Procoxal cavities open posteriorly. Mesocoxae closed laterally to mesepimeron (Fig.
Although first described under the name Hesperophanes guttaticollis, the holotype actually has a label indicating “guttatus”. This is one of the easiest species to recognize due to the yellow pubescent maculations on the pronotum. Only one other species, C. nigroapicale Dillon & Dillon has this feature. Ceresium guttaticolle has two patches on either side, subequal in length, while C. nigroapicale has three or four areas of yellowish pubescence on either side, with the apical noticeably larger. This species was originally described from Tahiti and is also known from Viti Levu, Taveuni, and the Lau Islands in Fiji. The subspecies Ceresium guttaticolle yapense Gressitt, 1956 is known from the Yap Islands, Micronesia. Specimens have been collected, mostly at lights, from July through October (
Ceresium lucidum:
Based on the holotype specimen (
Pronotum broadly arcuate, widest across middle, and almost as wide as long. Pronotum with sparse punctures and sparsely scattered pubescence elsewhere (Fig.
Venter of abdomen and thorax sparsely ochraceous pubescent throughout, not obscuring integument. Length of abdomen 3.82 mm. Prosternal process very narrow, gradually declivous, weakly notched and expanded at apex, less than 1/5 width of procoxa. Procoxal cavities widely open posteriorly. Mesocoxae closed laterally to mesepimeron (Fig.
The key characters show this species to be closest to C. epilais. Ceresium lucidum is distinguished by having the pronotum with a diffuse, dark macula at either side of middle, and being widest anterior of the midpoint while C. epilais lacks pronotal maculae and is widest medially at sides. This rare species is endemic to Fiji and known only from the holotype that was collected on Viti Levu at lights during October (
Ceresium nigroapicale:
Based on the holotype specimen (
Pronotum cylindrical, widest at basal third and slightly longer than wide. Pronotum with four dense patches of yellow pubescence on either side. Apical one largest in size and remaining three almost subequal in size, all arranged longitudinally on either side of pronotum. Pronotum glabrous at center with a few scattered yellow setae with large irregular punctures (Fig.
Venter of abdomen and thorax with sparse ochraceous pubescence throughout. Prosternal process narrow, approximately 1/4 width of procoxa, notched and expanded at apex. Procoxal cavities open posteriorly (Fig.
This is one of two species characterized by dense pubescent maculae on the pronotum, the other being Ceresium guttaticolle. That species has two patches on either side, subequal in length, while C. nigroapicale has three or four areas of yellowish pubescence on either side, with the apical noticeably larger. Ceresium nigroapicale is further distinguished by the elytra having diffusely darker coloration apically and laterally and very coarse punctation on the basal half. This is another rare species that is endemic to Fiji and known only from Viti Levu. Specimens have been collected in July and September by beating vegetation (
Hesperophanes olidus:
Based on a photograph of the holotype specimen (
Pronotum rounded, widest across middle, and as long as wide. Pronotum with fine, sparse and evenly spaced punctures throughout (Fig.
Venter of abdomen and thorax with sparse, ochraceous pubescence throughout. Prosternal process absent. Procoxal cavities open posteriorly. Mesocoxae closed laterally to mesepimeron (Fig.
This species is distinguished by having the pronotum with uniform, dense punctation, the third antennal segment extending to about the midpoint of pronotum, and the head, pronotum and scutellum with fine, sparse, ochraceous pubescence. It shares with C. scutellaris an incomplete prosternal process between the procoxae. Originally described as Hesperophanes, it is known from Viti Levu and the Lau Islands, Fiji and also recorded from Tahiti and Raiatea of the Society Islands of French Polynesia in the original description (
Ceresium promissum:
Based on the holotype specimen (
Pronotum broadly arcuate, widest across middle and slightly longer than wide; glabrous median line, vertically on basal center of pronotum. Pronotum with sparse punctures and sparsely scattered pubescence elsewhere (Fig.
Venter of abdomen and thorax with sparse, translucent pubescence throughout, not obscuring integument. Length of abdomen 4.04 mm. Prosternal process very narrow, only extending about halfway between procoxae which are nearly contiguous as a result. Procoxal cavities widely open posteriorly (Fig.
By the key characters, C. promissum is most similar to C. decorum. In C. promissum, the mesosternal process has its basal notch parallel-sided and the pronotum has a narrow, glabrous, impunctate line at the middle restricted to the posterior half. In C. decorum, the mesosternal process has the basal notch at an angle and the pronotum has the narrow, glabrous, impunctate line at middle centrally located. This species is endemic to Fiji and known only from Viti Levu where the holotype was collected in June (
Ceresium pubescens:
Based on the holotype and a paratype (
Pronotum uniformly arcuate, widest at middle, and slightly wider than long; not tuberculate. Calli absent. Pronotum with sparse yellow pubescence, denser at basal sides; center of disk mostly glabrous. Pronotum with sparse, ill-defined punctures (Fig.
Venter of abdomen and thorax with moderately dense, golden pubescence at sides, but very sparse golden pubescence along middle; except for prosternum which is densely pubescent throughout and on sides. Prosternal process moderately narrow, vertical and acutely declivous, about 1/3 width of procoxa, weakly notched and expanded at apex. Procoxal cavities open posteriorly (Fig.
One of the characters that define this species is the moderately dense, yellowish pubescence that extends from the sides of the pronotum across the base. In the key, it falls nearest C. grandipenne, but it easily distinguished by the much smaller size (always less than 20 mm while C. grandipenne is always larger than 21 mm). This species is widespread in Fiji and known from Viti Levu, Ovalau, Moala, and the Lau Islands (
Ceresium repandum Dillon & Dillon, 1952: 16, Fiji: Viti Levu, Nandarivatu, holotype (
Based on the holotype specimen (
Pronotum strongly arcuate, widest across slightly above middle, and slightly wider than long; small tubercles at sides located at the lateral lower half. Pronotum with sparse punctures and dense pubescence laterally (Fig.
Venter of abdomen and thorax with sparse, ochraceous pubescence throughout, not obscuring integument. Length of abdomen 4.95 mm. Prosternal process narrow, gradually declivous, weakly expanded at apex, approximately 1/4 width of procoxa. Procoxal cavities open posteriorly (Fig.
This species is very distinctive among the Fijian Ceresium by having very long antennae (extending beyond the elytral apices by more than 5 segments), by the laterally multi-tuberculate pronotum, and by the post-medial black macula on each elytron. It is most similar to C. tuberculatum in the key characters but can be distinguished from that species by having the pronotum strongly arcuate with dense, white pubescence at the sides (the pronotum in C. tuberculatum is quadrate with patchy yellow pubescence on sides and posterior margin). This species is endemic to Fiji and known only from Viti Levu where both known specimens were taken at lights in October (
Ceresium scutellaris:
Based on the holotype specimen (
Pronotum arcuate, slightly transverse, apex slightly narrower than base; tubercles absent. No calli. Pronotum with fine, sparse, evenly spaced golden pubescence throughout. Pronotum with fine and dense punctures (Fig.
Venter of abdomen and thorax with moderately dense, ochraceous pubescence at sides, but sparse pubescence along middle, except for prosternum which is sparsely pubescent throughout. Prosternal process very, weakly notched and not expanded at apex. Procoxal cavities open posteriorly (Fig.
This species was not included in the key in the original publication (
Ceresium striatipenne:
Based on the holotype and a paratype specimen (
Pronotum broadly arcuate, widest below middle, and transverse. Narrower at anteriorly than posteriorly. Pronotum with three longitudinally glabrous lines with moderately dense golden pubescence between glabrous lines and sparsely pubescent elsewhere. Pronotum with moderately dense punctures in center between glabrous lines and sparsely elsewhere (Fig.
Venter of abdomen and thorax with sparse ochraceous pubescence at sides with sparser pubescence along middle. Prosternal process narrow, weakly notched and expanded at apex. Procoxal cavities closed posteriorly (Fig.
The distinctive, longitudinal, glabrous striae characterize this species. The only other species with semi-regular glabrous areas on the elytra is C. vacillans, but in that species these regions are in the form of spots rather than lines. This species is endemic to Fiji and known only from Viti Levu where the type specimens were collected at lights in August (
Ceresium thyra:
Based on photograph of the holotype specimen (
Pronotum arcuate, widest across middle, and almost as long as wide. No tubercles or callus present. Pronotum with sparse ochraceous pubescence. Pronotum with sparse, ill-defined punctures (Fig.
Venter of abdomen with sparse white pubescence and metasternum with sparse white pubescence at center and moderately dense on sides. Mesosternum also moderately dense with white pubescence. Prosternal process moderately narrow, vertical and acutely declivous, approximately 1/3 width of procoxa, notched and expanded at apex. Procoxal cavities open posteriorly (Fig.
The very dense, nearly white pubescence of the scutellum is distinctive, along with the dorsally callous pronotum. This species is endemic to Fiji and known only from Viti Levu where specimens were collected in September (
Ceresium tuberculatum:
Based on the holotype specimen (
Ceresium tuberculatum Waqa & Lingafelter: a dorsal habitus, male paratype b head detail, male c pronotal detail, male d ventral view showing width of prosternal and mesosternal intercoxal processes, along with pubescence distribution e lateral view showing acutely declivous prosternal process, weakly tuberculate, acutely declivous mesosternal process, and laterally closed mesocoxa.
Pronotum quadrate, slightly widest anteriorly, and slightly wider than long; tuberculate at sides; constricted subbasally and apically. Raised tubercles present at middle of sides and anterolaterally. Three poorly-defined calli on disk: 1 medial and 2 anteromedial between middle callus and anterolateral tubercle. Pronotum with patchy ochraceous pubescence, denser at sides and posterior margin, slightly less dense anteriorly; center of disk mostly glabrous. Pronotum with sparse, poorly-defined punctures in males (except on smooth calli), only sparse depressions present in females (Fig.
Venter of abdomen and thorax with moderately dense, ochraceous pubescence at sides, but mostly glabrous along middle, except for prosternum which is densely pubescent. Prosternal process broad, vertical and acutely declivous, approximately 1/3 width of procoxa, weakly notched and expanded at apex. Procoxal cavities open posteriorly. Mesocoxae closed laterally to mesepimeron. Mesosternum rather acutely declivous, with small anterior tubercle, and sulcate anteriorly (Fig.
The prominent anterolateral pronotal tubercles, narrowly tapering pronotum posteriorly, and acutely declivous prosternal process are distinctive for this species. This recently described species is endemic to Fiji and known only from Gau and Viti Levu Islands where specimens have been collected in Malaise traps, mostly, from April through June and October through November (
Saperda unicolor: Fabricius 1787: 147, Amsterdam Island, French Southern Islands, holotype (BMNH).
Based on the original description (Fabricius 1787) and specimens from 1938, 2005 and 2007 surveys (FNIC,
Pronotum broadly arcuate quadrate, widest across middle, and as long as wide. Tubercles absent. Pronotum with a broad median line and a fine line slightly half-way between middle and sides on each side of pronotum. Pronotum with moderately dense to dense yellow pubescence. Pronotum with sparse, coarse punctures (Fig.
Venter of abdomen and metasternum with sparse yellow pubescence towards center and becoming denser on sides. Prosternal process moderately narrow, vertical and acutely declivous, about 1/4 width of procoxa, weakly notched and not expanded at apex. Procoxal cavities open posteriorly (Fig.
This species is somewhat variable and lacking a suite of very distinctive characters. In the key, it is distinguished by the pronotum lacking maculae and lateral tubercles but having several dorsal calli, and having pubescence of the head, pronotum, elytra and scutellum similar in density and coloration. This species is widespread and known from Mauritius, Seychelles, New Zealand, Waigeo Island, Papua New Guinea, Bismarck Archipelago, Solomon Islands, Vanuatu, Hawaii, and Fiji (
Ceresium vacillans:
Based on the holotype specimen (
Pronotum arcuate, wider across middle, transverse, apical margin narrower than base. Disk moderately dense with ochraceous pubescence, and coarsely punctate. Medially with a broad transversely ovate impression limited by two low tubercles in front, two behind and a fifth one in its center (Fig.
Venter of abdomen with moderately dense, ochraceous pubescence at sides, sparse ochraceous pubescence along middle, except for prosternum which is sparsely pubescent throughout and on sides. Prosternal process broad, vertical and acutely declivous, about 1/4 width of procoxa, weakly notched and expanded at apex. Procoxal cavities open posteriorly (Fig.
This species is most similar to C. striatipenne in that it possesses glabrous regions on the elytra, however in this species, the glabrous regions are irregular and small rather than forming narrow lines as in C. striatipenne. This species is endemic to Fiji and known only from Viti Levu and the Lau Islands where specimens have been collected in July and September (
Diagnostic features in the key include easily coded character states: presence/absence of a macula on the pronotum; shape and color of the macula on pronotum; shape of pronotum (i.e. tuberculate, strongly/weakly arcuate); color of pubescence on pronotum; density of pubescence on pronotum; pronotum with or without calli; and elytra with/without a glabrous line or macula.
1 | Pronotum with yellow macula | 2 |
– | Pronotum without yellow macula | 3 |
2(1) | Pronotum with two dense areas of yellowish pubescence on either side, subequal in length | C. guttaticolle (Fairmaire) |
– | Pronotum with three or four areas of yellowish pubescence on either side, apical one largest | C. nigroapicale Dillon & Dillon |
3(1) | Pronotum tuberculate laterally | 4 |
– | Pronotum not tuberculate | 5 |
4(3) | Pronotum strongly arcuate with white pubescence denser on either lateral sides | C. repandum Dillon & Dillon |
– | Pronotum quadrate, posteriorly narrowed, with patchy yellow pubescence denser on either sides and posterior margin | C. tuberculatum Waqa & Lingafelter |
5(3) | Pronotum with calli | 6 |
– | Pronotum without calli | 7 |
6(5) | Head and pronotum with moderately dense yellowish pubescence. Scutellum with pubescence of similar color as that on pronotum and elytra | C. unicolor (Fabricius) |
– | Head and pronotum with sparse ochraceous pubescence. Scutellum with much paler pubescence than on pronotum and elytra | C. thyra Dillon & Dillon |
7(5) | Mesosternal process tuberculate anteriorly | 8 |
– | Mesosternal process not tuberculate | 9 |
8(7) | Pronotum quadrate in shape. Integument rather opaque, not strongly shining. Large species (>21 mm in length) | C. grandipenne Fairmaire |
– | Pronotum uniformly rounded laterally. Integument very shiny. Moderate to small species (<20 mm in length) | C. pubescens Dillon & Dillon |
9(7) | Elytra with glabrous lines or spots between pubescence | 10 |
– | Elytra without glabrous lines or maculae | 11 |
10(9) | Elytra with fine glabrous linear regions between pubescence. Prosternal process very narrow between procoxae | C. striatipenne Dillon & Dillon |
– | Elytra with small scattered glabrous spots between pubescent patches. Prosternal process moderately wide between procoxae | C. vacillans Dillon & Dillon |
11(9) | Prosternal process incomplete between procoxae | 12 |
– | Prosternal process fully extending between procoxae | 13 |
12(11) | Pronotum with uneven punctation. Third antennal segment extending nearly to posterior margin of pronotum. Head, pronotum and scutellum with dense yellowish tomentum | C. scutellaris Dillon & Dillon |
– | Pronotum with uniform, dense punctation. Third antennal segment extending to about midpoint of pronotum. Head, pronotum and scutellum with finely sparse ochraceous pubescence | C. olidum (Fairmaire) |
13(11) | Pronotum strongly arcuate laterally | 14 |
– | Pronotum weakly arcuate/feebly elongate | 15 |
14(13) | Pronotum almost hexagonal in shape, with a diffuse, dark macula in the integument either side of middle, widest before middle | C. lucidum Dillon & Dillon |
– | Pronotum with sides broadly rounded, without maculae on integument, widest medially | C. epilais Dillon & Dillon |
15(13) | Elytra with apical third paler than rest | C. gracilipes Fairmaire |
– | Elytra uniformly colored | 16 |
16(15) | Mesosternal process basal notch parallel sided. Pronotum with narrow, glabrous, impunctate line at middle restricted to posterior half | C. promissum Dillon & Dillon |
– | Mesosternal process basal notch at an angle. Pronotum with narrow, glabrous, impunctate line at middle centrally located | C. decorum Dillon & Dillon |
This study was possible through funding from the Darwin Initiative project: “Focus for Fiji: Insect Inventories for Biodiversity Assessments” (Ref: 15007). Thank you to our project partners, The University of Sussex, UK especially Dr. Alan Stewart. We also thank Prof. Bill Aalbersberg and Marika Tuiwawa (IAS,