Ninety-eight new species of Trigonopterus weevils from Sundaland and the Lesser Sunda Islands

Abstract The genus Trigonopterus Fauvel, 1862 is highly diverse in Melanesia. Only one species, Trigonopterus amphoralis Marshall, 1925 was so far recorded West of Wallace’s Line (Eastern Sumatra). Based on focused field-work the fauna from Sundaland (Sumatra, Java, Bali, Palawan) and the Lesser Sunda Islands (Lombok, Sumbawa, Flores) is here revised. We redescribe Trigonopterus amphoralis Marshall and describe an additional 98 new species: Trigonopterus acuminatus sp. n., Trigonopterus aeneomicans sp. n., Trigonopterus alaspurwensis sp. n., Trigonopterus allopatricus sp. n., Trigonopterus allotopus sp. n., Trigonopterus angulicollis sp. n., Trigonopterus argopurensis sp. n., Trigonopterus arjunensis sp. n., Trigonopterus asper sp. n., Trigonopterus attenboroughi sp. n., Trigonopterus baliensis sp. n., Trigonopterus batukarensis sp. n., Trigonopterus bawangensis sp. n., Trigonopterus binodulus sp. n., Trigonopterus bornensis sp. n., Trigonopterus cahyoi sp. n., Trigonopterus costipennis sp. n., Trigonopterus cuprescens sp. n., Trigonopterus cupreus sp. n., Trigonopterus dacrycarpi sp. n., Trigonopterus delapan sp. n., Trigonopterus dentipes sp. n., Trigonopterus diengensis sp. n., Trigonopterus dimorphus sp. n., Trigonopterus disruptus sp. n., Trigonopterus dua sp. n., Trigonopterus duabelas sp. n., Trigonopterus echinatus sp. n., Trigonopterus empat sp. n., Trigonopterus enam sp. n., Trigonopterus fissitarsis sp. n., Trigonopterus florensis sp. n., Trigonopterus foveatus sp. n., Trigonopterus fulgidus sp. n., Trigonopterus gedensis sp. n., Trigonopterus halimunensis sp. n., Trigonopterus honjensis sp. n., Trigonopterus ijensis sp. n., Trigonopterus javensis sp. n., Trigonopterus kalimantanensis sp. n., Trigonopterus kintamanensis sp. n., Trigonopterus klatakanensis sp. n., Trigonopterus lampungensis sp. n., Trigonopterus latipes sp. n., Trigonopterus lima sp. n., Trigonopterus lombokensis sp. n., Trigonopterus merubetirensis sp. n., Trigonopterus mesehensis sp. n., Trigonopterus micans sp. n., Trigonopterus misellus sp. n., Trigonopterus palawanensis sp. n., Trigonopterus pangandaranensis sp. n., Trigonopterus paraflorensis sp. n., Trigonopterus pararugosus sp. n., Trigonopterus parasumbawensis sp. n., Trigonopterus pauxillus sp. n., Trigonopterus payungensis sp. n., Trigonopterus porcatus sp. n., Trigonopterus pseudoflorensis sp. n., Trigonopterus pseudosumbawensis sp. n., Trigonopterus punctatoseriatus sp. n., Trigonopterus ranakensis sp. n., Trigonopterus relictus sp. n., Trigonopterus rinjaniensis sp. n., Trigonopterus roensis sp. n., Trigonopterus rugosostriatus sp. n., Trigonopterus rugosus sp. n., Trigonopterus rutengensis sp. n., Trigonopterus saltator sp. n., Trigonopterus santubongensis sp. n., Trigonopterus sasak sp. n., Trigonopterus satu sp. n., Trigonopterus schulzi sp. n., Trigonopterus sebelas sp. n., Trigonopterus sembilan sp. n., Trigonopterus sepuluh sp. n., Trigonopterus seriatus sp. n., Trigonopterus serratifemur sp. n., Trigonopterus setifer sp. n., Trigonopterus silvestris sp. n., Trigonopterus singkawangensis sp. n., Trigonopterus singularis sp. n., Trigonopterus sinuatus sp. n., Trigonopterus squalidus sp. n., Trigonopterus sumatrensis sp. n., Trigonopterus sumbawensis sp. n., Trigonopterus sundaicus sp. n., Trigonopterus suturalis sp. n., Trigonopterus syarbis sp. n., Trigonopterus telagensis sp. n., Trigonopterus tepalensis sp. n., Trigonopterus tiga sp. n., Trigonopterus trigonopterus sp. n., Trigonopterus tujuh sp. n., Trigonopterus ujungkulonensis sp. n., Trigonopterus variolosus sp. n., Trigonopterus vulcanicus sp. n., Trigonopterus wallacei sp. n.. All new species are authored by the taxonomist-in-charge, Alexander Riedel. Most species belong to the litter fauna of primary wet evergreen forests. This habitat has become highly fragmented in the study area and many of its remnants harbor endemic species. Conservation measures should be intensified, especially in smaller and less famous sites to minimize the number of species threatened by extinction.


Introduction
Trigonopterus Fauvel, a genus of flightless weevils placed in the subfamily Cryptorhynchinae of Curculionidae (Alonso-Zarazaga and Lyal 1999), is hyperdiverse in the Papuan region (Riedel et al. 2010;Tänzler et al. 2012). However, only a few species have been described from west of the Moluccas to date. Besides three species from the Philippines [T. bakeri (Hustache, 1925), T. paucisquamosus (Heller, 1915), T. semirubrus (Hustache, 1925)] and one from Sulawesi [T. fulvicornis (Pascoe, 1885)], there is only one more species described from East Sumatra [T. amphoralis (Marshall)]. The conspicuous gap in distribution is here revealed as a sampling artifact and will be remedied with the present publication. The area covered herein includes parts of Sundaland (i.e. Sumatra, Java, Borneo, and the Philippine island of Palawan) and the Lesser Sunda Islands. No species of Trigonopterus is known to us from the Malay Peninsula and the western and central parts of Sumatra. The intensive field work for this study largely focused on East Sumatra, Java and the Lesser Sunda Islands, while material available from only a few localities in Borneo and Palawan could be included. Thus, many more species can be expected from these islands. The fauna of Sulawesi will be treated in a separate publication.
We have previously established that Trigonopterus weevils are suitable for accelerated taxonomic study combining morphology and the DNA barcoding approach using mitochondrial cox1 data (Riedel et al. 2013a, b;Tänzler et al. 2012); herein we will use the same strategy to provide "faces and names" to an additional 98 undescribed species. While in our earlier study (Riedel et al. 2013b) we tried to name only selected representatives covering all species groups, we now revise all species of a focal region. This newly established taxonomic foundation will be of immediate use to our studies on the evolution and biogeography of Trigonopterus (e.g. Tänzler et al. 2014).

Materials and methods
This study is based on > 4,000 specimens of Trigonopterus, collected specifically for a project on this genus. Unless otherwise stated, specimens were collected by sifting the litter of primary forests with subsequent extraction by hand or, more efficiently, using eclectors (Besuchet et al. 1987). Holotypes were selected from the 703 sequenced specimens; their DNA had been extracted nondestructively as described by Riedel et al. (2010). The genitalia of most specimens did not require maceration after DNAextraction; they could be directly stained with an alcoholic Chlorazol Black solution and stored in glycerol in microvials attached to the pin of the specimens. Genitalia of collection specimens or specimens whose abdominal muscle tissue was not sufficiently digested after DNA extraction were macerated with 10% KOH and rinsed in diluted acetic acid before staining. Illustrations of habitus and genitalia were prepared from holotypes. Finally, type series were supplemented with specimens stored in ethanol and older material from the dry collection. As always the case in paratypes, there is a chance that some of these are incorrectly assigned; this is especially true for specimens without sequence data as an identification based on external morphological characters is more prone to error than an identification based on a cox1 sequence (Tänzler et al. 2012). Several different species belonging to the T. relictus-group occur sympatrically in Sumbawa and Flores. Since it was not possible to separate these sibling species without the extraction of male genitalia and / or their sequence data, a substantial number of specimens were not included in any type series. Type depositories are cited using the following codens:

ARC
Alexander Riedel Collection, stored in SMNK, Germany.
The methods applied for DNA sequencing and sequence analysis are described by Riedel et al. (2010) and Tänzler et al. (2012). Morphological descriptions are limited to major diagnostic characters as outlined by Riedel et al. (2013a, b). Negative character states (i.e. the absence of a character) are only mentioned explicitly where it appears appropriate. For example, there are some species with scale-bearing punctures in which the insertion of the scale has shifted from the center to the margin of the puncture. In these cases, the character is described, but for the majority of species where it is placed in the center it is not mentioned. Common practice would require stating explicitly "scale inserted in center of puncture". Although formally accurate, in groups comprising hundreds of species this leads to inflated descriptions that distract the reader from the important information by enumerating the absence of rare character states.
Morphological terminology follows Beutel and Leschen (2005) and Leschen et al. (2009), i.e. the terms "mesoventrite" / "metaventrite" are used instead of "mesosternite" / "metasternite", and "mesanepisternum" / "metanepisternum" instead of "mesepisternum" / "metepisternum"; "penis" is used instead of "aedeagus" as the tegmen is usually without useful characters in Trigonopterus and therefore omitted from species descriptions. Descriptions were prepared using a Leica MZ16 dissecting microscope and a fluorescent desk lamp for illumination. Measurements were taken with the help of an ocular grid. The length of the body was measured in dorsal aspect from the elytral apex to the front of the pronotum. Width of elytra was measured between the humeri at their greatest extent and across both elytra. Legs were described in an idealized laterally extended position; there is a dorsal / ventral and an anterior / posterior surface. Habitus illustrations were compiled using the Automontage© software (Syncroscopy, Cambridge, UK) with a JVC KY70 camera (JVC Professional Products) adapted to a Leica Z6 APO (Leica Microsystems, Wetzlar, Germany). Photographic illustrations of genitalia were made using the same software / camera combination adapted to a Zeiss Imager microscope, and for this purpose the genitalia were embedded in glycerol gelatin as described by Riedel (2005). Genitalia were photographed with their longitudinal axis somewhat lifted anteriorly, to adequately illustrate structures of the curved down apex. All photographs were enhanced using Adobe Photoshop CS2. However, care was taken not to obscure or alter any features of the specimens illustrated. Sequence data were submitted to the European Molecular Biology Laboratory (EMBL), and the accession numbers are provided under each species e.g. as "(EMBL # FN429236)".
Etymology. This epithet is based on the Latin adjective acuminatus (pointed) and refers to the shape of the elytra.
Etymology. This epithet is a combination of the Latin adjectives aeneus (copper, bronze) and micans (shining) and refers to the metallic lustre of this species´ elytra.

Trigonopterus alaspurwensis Riedel, sp. n.
http://zoobank.org/3A02E4CA-376A-4332-9DD8-CC2856C2EE95 Diagnostic description. Holotype, male (Fig. 3a). Length 3.47 mm. Color of legs and head ferruginous, transverse band of elytra polished black, remainder with greenish coppery lustre. Body elongate; in dorsal aspect with marked constriction between pronotum and elytron; in profile dorsally flat. Rostrum with median and pair of submedian ridges; intervening furrows each with row of punctures and suberect piliform scales; epistome simple. Pronotum anterolaterally markedly projecting, rounded; with subapical constriction; disk densely punctate; punctures partly elongate and / or arranged in confluent rows forming rhombus-like pattern near midline; each puncture containing piliform white scale; medially with glabrous costa. Elytral intervals bearing each one row of course punctures flanked by glabrous ridges; striae hard to distinguish from secondary rows of punctures; punctures containing long, recumbent, cream-colored scales; at middle with transverse subglabrous band; interval 7 swollen subapically, forming lateral edge; apex subtruncate, sutural interval not protruding. Femora edentate; anteroventral ridge indistinct. Metafemur subapically with stridulatory patch. Dorsal edge of tibiae subbasally with angulation extended as acute tooth. Abdominal ventrite 5 with shallow concave pit, basally and laterally with long suberect scales. Penis (Fig. 3b) with body short, sides subparallel; apex broadly rounded; transfer apparatus complex, rotated to the left; apodemes 3.0 × as long as body; ductus ejaculatorius without bulbus. Intraspecific variation.  mm. Females more slender than males. Female rostrum with median and pair of submedian glabrous costae. Female elytra with lateral contour convex, widest near middle; male elytra widest between humeri; elytral sculpture of females less distinct, longitudinal ridges weak or absent, transverse band near middle indistinct, sparsely punctate. Female abdominal ventrite 5 flat.
Etymology. This epithet is based on the Greek allos (other) and the Latin patria (homeland) and refers to its fragmented distribution.

Trigonopterus allotopus
Etymology. This epithet is the latinized form of a combination of the Greek adjective allos (foreign) and the noun topos (place). The species marks the Southwestern limit of the T. politus-group´s distribution which is most diverse in the Papuan region.
Notes. Trigonopterus allotopus Riedel, sp. n. was coded as "Trigonopterus sp. 331" by Tänzler et al. (2014). The holotype was taken from a sample of sifted leaf litter; however, based on observations of the other species of the T. politus-group its occurrence on foliage appears more likely.
Notes. Trigonopterus asper Riedel, sp. n. was coded as "Trigonopterus sp. 359". It is closely related to T. variolosus Riedel, sp. n. from which it can be separated by a larger penis with a longer flagellum. The minimal p-distance between both species is 9.5%.

23.
Trigonopterus dentipes Riedel, sp. n. http://zoobank.org/550B7704-235F-40E4-B006-49B32D239AF6 Diagnostic description. Holotype, male (Fig. 23a). Length 3.84 mm. Color of antennae ferruginous; basal third of elytra and legs dark ferruginous; remainder black. Body in dorsal aspect with marked constriction between pronotum and elytron; in profile dorsally flat, apically convex. Rostrum with median and pair of submedian ridges; intervening furrows each with sparse row of erect piliform scales; epistome with transverse ridge forming submedian pair of small denticles. Pronotum with sides subparallel, rounded to indistinct subapical constriction; disk densely punctate, reticulate; with indistinct median ridge; with swelling in anterior half. Elytra with striae near base and apex distinct; intervals partly swollen or with coarse punctures each bearing small, suberect, cream-colored scale; transverse band at middle with indistinct striae, intervals subglabrous, sparsely punctate; apex subangulate. Anteroventral ridge of femora forming large tooth. Metafemur subapically with stridulatory patch. Dorsal edge of tibiae with subbasal angulation dentate. Abdominal ventrites 1-2 concave, subglabrous; abdominal ventrite 5 flat, coarsely punctate, with sparse erect piliform scales. Penis ( Fig.  23b) with sides of body subparallel; apex bisinuate, with median notch; transfer apparatus compact, symmetrical, but slightly tilted to the left; apodemes 2.5 × as long as body; ductus ejaculatorius without bulbus. Intraspecific variation. Length 3.04-4.04 mm. Coloration of elytral base ranging from orange-ferruginous to dark ferruginous and almost black. Female rostrum with median and pair of submedian glabrous costae; epistome simple. Female elytra more slender, with lateral contour convex to apex; punctures sparser and smaller than in male; male elytra relatively broad between humeri, converging in almost straight line to apex. Etymology. This epithet is based on the combination of the Latin nouns dens (tooth) and pes (foot).

Trigonopterus disruptus
Notes. Trigonopterus dua Riedel, sp. n. was coded as "Trigonopterus sp. 284".  Etymology. This epithet is based on the Indonesian word for "twelve" and is treated as a noun in apposition.
Notes. Trigonopterus echinatus Riedel, sp. n. was coded as "Trigonopterus sp. 337". Etymology. This epithet is based on the Indonesian word for "six" and is treated as a noun in apposition.
Etymology. This epithet is based on a combination of the Latin adjective fissus (cleft) and the Greek noun tarsos and refers to the shape of the protarsi.

Trigonopterus florensis
Diagnostic description. Holotype, male (Fig. 33a). Length 1.72 mm. Color of antennae and tarsi ferruginous, remainder black. Body in dorsal aspect with marked constriction between pronotum and elytron; with distinct constriction in profile. Rostrum with median ridge and pair of submedian ridges, anteriorly coarsely punctate-scabrous; epistome with transverse, subangulate ridge. Pronotum with subapical constriction; disk coarsely punctate-reticulate, sparsely setose; with pair of curved sublateral impressions; medially swollen. Elytra relatively compact; with striae deeply impressed, each with row of short suberect bristles; intervals costate, subglabrous; apex narrow, round-ed. Femora each with small tooth. Metafemur subapically with stridulatory patch. Abdominal ventrite 5 coarsely punctate, with shallow median impression bordered by pair of weak longitudinal costae. Penis (Fig. 33b) with sides subparallel, in apical third markedly converging to narrow subglabrous apex; transfer apparatus flagelliform, 3.9 × as long as body; apodemes 3.5 × as long as body; ductus ejaculatorius torn and apical portion missing. Intraspecific variation. Length 1.48-2.04 mm. Color of elytra dark ferruginous to black. Female rostrum dorsally in apical half subglabrous, with submedian rows of sparse minute punctures, with dorsolateral pair of furrows; epistome simple. Pronotum in smaller specimens narrower, in large specimens wider. Elytra in larger specimens with humeri more distinctly subangularly projecting laterad, in smaller specimens evenly rounded; intervals weakly costate in smaller specimens, markedly costate or carinate in larger specimens. Penis with flagelliform transfer apparatus 3.9-4.0 × as long as body; apodemes 3.2-3.7 × as long as body. Etymology. This epithet is based on the island of Flores. Notes. Trigonopterus florensis Riedel, sp. n. was coded as "Trigonopterus sp. 440". Morphologically it is very similar to T. pseudoflorensis Riedel, sp. n. and T. paraflorensis Riedel, sp. n. but its cox1 sequences differ 6.69%, respectively 7.75% smallest interspecific p-distance.
Notes. Trigonopterus pararugosus Riedel, sp. n. was coded as "Trigonopterus sp. 327" by Tänzler et al. (2014). The interspecific p-distance of cox1 to T. rugosus Riedel, sp. n. is 5.6-7.2%. Morphologically no clear differences could be detected and it is assumed that both represent a pair of cryptic species.
Notes. Trigonopterus porcatus Riedel, sp. n. was coded as "Trigonopterus sp. 370". Etymology. This epithet is based on the Greek prefix pseudo (false) and the name of Trigonopterus florensis Riedel, sp. n., a sibling species.
Notes. Trigonopterus rugosus Riedel, sp. n. was coded as "Trigonopterus sp. 280" by Tänzler et al. (2014). The minimal p-distances of cox1 to T. pararugosus Riedel, sp. n. is 5.6-7.2%. Morphologically no clear differences could be detected and it is assumed that both represent a pair of cryptic species.
Etymology. This epithet is based on the Latin noun saltator (leaper) and refers to the biogeographic pattern where close relatives of this species are found on islands to the West.
Etymology. This epithet is based on the Sasak tribe traditionally inhabiting the island of Lombok. It is a noun in apposition.
Etymology. This species is named in honour of Andreas Schulz (Leverkusen, Germany), a successful collector of edaphic arthropods.
Etymology. This epithet is based on the Latin adjective seriatus (arranged in rows) and refers to the elytral scales.

Trigonopterus serratifemur
Etymology. This epithet is a combination of the Latin nouns serra (saw) and femur (thigh) and is to be treated as noun in apposition.
Etymology. This epithet is a combination of the Latin noun seta (bristle) and the suffix -fer (bear, carry) and refers to the elytral vestiture.

Trigonopterus silvestris
constriction. Rostrum with median carina terminating on forehead; with pair of submedian ridges; intervening furrows each with row of erect, piliform scales; epistome with transverse, angulate ridge forming minute median denticle. Pronotum without distinct subapical constriction; disk densely punctate, interspaces glabrous; each puncture containing one small scale. Elytra with striae deeply impressed; each with row of narrow, suberect scales; intervals weakly carinate, nude, coriaceous; interval 7 swollen subapically, laterally weakly projecting; apex extended ventrad, beak-shaped. Metafemur with crenulate anteroventral ridge terminating with small tooth; subapically with stridulatory patch and transverse row of denticles. Metatibia in basal half with dorsal edge denticulate. Abdominal ventrite 5 flat, subapically with shallow pit. Penis (Fig.  83b) with body in profile markedly curved ventrad; in dorsal aspect sides basally concave, before apex subparallel; apex medially with small rounded extension; apo demes 1.6 × as long as body; ductus ejaculatorius without bulbus. Intraspecific variation. Etymology. This epithet is based on the Latin adjective singularis (alone) and refers to the fact that no other Trigonopterus species could be found on the type locality.
Etymology. This epithet is based on the Latin adjective sinuatus (bent) and refers to the elytral outline.
Etymology. This epithet is based on the Latin adjective variolosus (scarred) and refers to the species´ rough sculpture.

Discussion
Herein, we apply our fast track taxonomy approach (Riedel et al. 2013a) to revise the entire Trigonopterus fauna of a defined region. The proportion of closely related species to be separated was higher than in our earlier work covering representatives of different species groups (Riedel et al. 2013b), but this did not cause any complications. Diagnosis of species using cox1 sequences was straightforward and the question where to draw the line between allopatric populations and putative species entities usually could be answered by the evaluation of morphological, especially genital characters. In a few cases, especially in the T. relictus-group, sibling species could be revealed that occur syntopically. After recognizing a subdivision into well separated clades of relatively high divergence we reassessed genital characters. We found that the length of the flagellum was correlated with these clusters. It can only be speculated that their discovery would not have been possible with morphological taxonomy alone as the taxonomist in charge had initially relegated these differences to intraspecific variation by lumping a number of them. At the start of this project and based on literature the high diversity of Trigonopterus in the Papuan region (Riedel et al. 2010;Tänzler et al. 2012) seemed to contrast with a relatively poor representation in the Philippines (three described species : Heller 1915;Hustache 1925) and Sulawesi (one described species: Riedel 2011), while its presence in Sundaland appeared questionable -the single species described by Marshall (1925) from East Sumatra looked out of place and more like the result of a mistake than representing a reliable record.
Step by step, extensive field work revealed this picture to be a simple artifact. In fact, the islands of the Sunda Arc and Borneo each harbour a rich and so far overlooked fauna, at least in places with wet primary forest. However, unlike in New Guinea and Wallacea where many species can be collected from foliage, the fauna of the Sunda Islands is largely restricted to the litter layer more difficult to sample and thus largely neglected by collectors. Moreover, Trigonopterus weevils usually fall into the category of "small beetles" which have a higher chance to be undescribed than beetles of larger body size (Stork et al. 2008).
The field work for this study focused on eastern parts of Sumatra, Java and the Lesser Sunda Islands. Materials stored in museum collections neither contained Trigonopterus from the western parts of Sumatra, nor from the Malay Peninsula. A dedicated search in the field could possibly lead to interesting discoveries, but equally well the genus´ real area of distribution excludes this region or parts of it. More promising for future discoveries of species are Borneo and Palawan where only material from a few localities was available. Borneo obviously possesses a rich fauna of Trigonopterus and its species number will be magnitudes higher than the ten species recorded so far. Species discovery on Java (35 species recorded), Bali (8 species recorded), and Lombok (7 species recorded) may approach saturation, while additional species are likely to be found on Sumatra (7 species recorded), Sumbawa (12 species recorded), and Flores (18 species recorded).
Most localities sampled by us harbour at least one species of Trigonopterus; in some places many more were found, such as seven species each at Mount Sawal of West Java, and Mount Ranaka of Flores Island. Although these figures are dwarfed by comparable localities of New Guinea (Riedel et al. 2010), the cumulative number of highly endemic species found on the Sunda Islands is substantial. A few of the species found in the montane forests of West Java are of relatively wide distribution, (e.g. T. allopatricus Riedel, sp. n., T. javensis Riedel, sp. n., T. vulcanicus Riedel, sp. n.), but none cover the entire island. Species with a narrower distribution range can be found on somewhat isolated mountain blocks with suitable vegetation, e.g. T. dimorphus Riedel, sp. n. and T. halimunensis Riedel, sp. n. on Mt. Halimun-Salak, T. angulicollis Riedel, sp. n. and T. gedensis Riedel, sp. n. on Mt. Gede. For lowland habitats the original degree of endemism is harder to judge since the areas of lowland primary forest remaining today are very restricted themselves. The two species recorded for Ujung Kulon National Park are found nowhere else but in this last major area of primary lowland forest of western Java. Similarly, the species found in Alas Purwo National Park and the two species found in Meru Betiri National Park are also restricted to their respective localities, although the two are separated by less than 60 km distance. Such a distance could easily straddle geological, respectively ecological boundaries effectively separating populations of flightless beetles. At the same time, it raises the question how many species once inhabiting the other areas of Java´s lowland forest have become extinct when the land was converted to agricultural use.
Wide areas of East Java and the Lesser Sunda Islands are markedly influenced by seasonal climate resulting in extensive monsoon forests, while wet evergreen forests persist on the slopes of higher mountains (Whitten et al. 1996). Trigonopterus species are restricted to the latter areas, and the monsoon forests are a habitat unsuitable to them, just like the vegetation altered by human influence. Even before the arrival of humans on the Sunda Islands the habitats of Trigonopterus were probably somewhat patchy for climatic reasons. With agriculture changing the land and human population increasing, areas of wet evergreen forests became increasingly fragmented and at times limited to a few square kilometers or less. Besides the usual risks that come with small areas of habitat for animals, additional factors pose serious hazards to the species inhabiting these forests: 1) Many of the mountains supporting these forests are active or dormant volcanoes. Eruptions may destroy major portions of the habitat. During our sampling campaign violent eruptions of Mount Merapi destroyed the last remaining area of primary forest on this mountain. 2) With increasing accessibility spots of natural beauty such as pockets of wet evergreen forests become more vulnerable to illegal logging and to disasters such as wildland fires. During times of drought a cigarette or a campfire may be enough to wipe out the remaining habitat. A wide and sealed road built for the purpose of recreation gave us easy access to a small fragment of wet montane forest on slope of Mount Wilis. It can only be hoped that the road´s impact will not be fatal to T. acuminatus Riedel, sp. n., a species exclusive to this area. 3) Many of the remaining wet evergreen forests stand on fertile grounds highly suitable to cultivate vegetables. With some of the highest population densities worldwide, it is not surprising that in Java, Bali and Lombok gardens tend to expand on the mountain slopes and encroach even on protected forests. Many Trigonopterus species have constraints in terms of elevation: For example, T. argopurensis Riedel, sp. n. was found to a maximum elevation of 1785 m. Although a larger forest area exists on the upper slopes of Mt. Argopuro, it seems to be unsuitable to this particular species which is cornered by coffee gardens in its lower range.
Looking at the distribution of Trigonopterus species in the Sunda Arc and the areas of remaining primary forests, it appears likely that some of these newly discovered species will become extinct in the next few decades. The blame will be largely on human activities which have reduced the once extensive areas of forest to small fragments. It is our responsibility to help preserving these remaining areas of habitat. We should intensify our efforts especially with those forests harbouring endemic species but nevertheless holding a relatively weak conservation status, as exemplified by the reserves of Mount Sawal and Mount Ranaka. In these cases, a limited investment in better protection could achieve a significant improvement for species conservation.
Herein, we provide faces to 98 hitherto unknown species by publishing their descriptions and images, in parallel also on the wiki-site Species-ID. The new names will be useful to deposit scientific data reliably and sustainably. Separate studies on the phylogeny and distribution patterns of Trigonopterus are in progress and will build on this taxonomic foundation. Most of all, it is hoped that knowledge of this previously unknown fauna will create an awareness for the conservation value of the remaining fragments of wet evergreen primary forest in the region. There may be a certain redundancy of conservation areas when we look at the distribution of many vertebrates -however, the larger portion of biodiversity as represented by arthropods exhibits a different picture. The message that a study of flightless weevils of the Sunda Arc conveys is clear: with almost every area of remaining primary forest being destroyed we will lose some more species -with or without names.