High diversity and endemism in the genus Cautires Waterhouse, 1879 (Coleoptera: Lycidae) from the Malay mountain forests, with the descriptions of fourteen new species

Abstract. We identified a high diversity in the net-winged beetles of the genus Cautires in Peninsular Malaysia. Fourteen new species are described: Cautires alexae sp. nov., C. andujari sp. nov., C. arribasae sp. nov., C. berembanensis sp. nov., C. campestris sp. nov., C. communis sp. nov., C. jasarensis sp. nov., C. katarinae sp. nov., C. kirstenae sp. nov., C. kotatinggensis sp. nov., C. linardi sp. nov., C. maseki sp. nov., C. pahangensis sp. nov. and C. renatae sp. nov. seven previously described species are discussed, illustrated and differential diagnoses provided; all species are keyed. the Cautires species differ in a limited number of diagnostic characters, namely in the shape of male antennae, the relative size of eyes and in the shape of the male genitalia. The females are difficult to assign to a conspecific male due to high intraspecific variability. The characteristically low dispersal propensity of net-winged beetles lead to the evolution of the unique fauna in the Malay mountains and despite an extensive study of the type material we recorded only a single species of Cautires occurring simultaneously in sumatra. We suggest that the Malay mountain fauna is highly endemic and evolved in situ.


Introduction
the high diversity of beetles in tropical regions remains poorly studied and the number of undescribed taxa in the randomly collected samples is often substantially higher than the number of known species.Such lack of knowledge is to be expected in relation to under-investigated and long-inaccessible regions such as New Guinea (Riedel et al. 2013;Bocek & Bocak 2016), but, at least in the case of net-winged beetles (Lycidae), we can find a high proportion of undescribed taxa in the whole tropics.This is also true for areas where entomological research has a long tradition, such as Sulawesi (Bocak 2000), the Philippines (Weiszenstein & Bocak 2011) and the Great Sundas (Masek et al. 2015).the recent DNA-based study dealing with the Cautires obsoletus species group, i.e., the former genus Bulenides Waterhouse, 1879 (Jiruskova & Bocak 2015), revealed quite a high number of unknown species, as was also the case in recently collected material from the Malay Peninsula.This region was intensively studied from the late 19 th century until WWii (Waterhouse 1879;Pic 1925Pic , kleine 1930aPic , b, 1933)), but has since been omitted from studies.
the Cautires is placed in the tribe Metriorrhynchini, which is the largest lineage of Lycidae as regards the number of species (1200 spp. in 41 genera in the old World tropics, kleine 1933;sklenarova et al. 2013) and which, along with Platerodini, is the most common group of net-winged beetles in the Orient.Almost 100 species of Cautires have been reported from Sundaland (Kleine 1933;Bocak 2002), whereas the recent molecular study dealing with the delimitation of genera in Metriorrhynchini has shown that the fauna of sumatra, Borneo and the Malay Peninsula seldom share any common species and that even the mountain ranges within a single island have a highly endemic fauna (Sklenarova et al. 2014).the species' high turnover is supposedly a result of biological characteristics of net-winged beetles.Lycidae live under the canopy and, although winged and capable of flight, they have a tendency to remain in the low strata of the forest and do not disperse easily.The low dispersal propensity of net-winged beetles leads to diversification in situ and limited dispersal between islands or mountain ranges (Li et al. 2015;Masek et al. 2015).Cautires larvae mainly evolve on the ground in wood at various stages of decomposition.They suck liquids with rich microbial life from small-size organic detritus such as rotten twigs.They can be collected from under the bark of dead tree trunks (Bocak & Matsuda 2003).Here, we present an alpha-taxonomic review of Cautires from the Malay Peninsula.The first species from Malaya were described by the end of the 19 th century (Waterhouse 1879;kirsch 1875), but the fauna was only explored further in the 1920s and 30s when Pic (1925) and Kleine (1930a, b) reported several Cautires species in this region.Only a few of them were collected in the mountain forests at that time; most of the field work took place along the coast in the easily accessible lowlands and frequently visited places which were close to Malacca and Kuala Lumpur.Additionally, some species were described from the Penang and Langkawi islands.Due to the inaccessibility of the Malay inland until the late 1960s, the fauna of the mountain ranges remained poorly studied.recently, an extensive collection of the Malay Cautires was assembled from the Cameron Highlands.The study deals with all species bearing more than three areolae in the pronotum, and this group of species corresponds with the original narrow delimitation of Cautires (kleine 1933;Bocak 2002;but not Dudkova &Bocak 2010 andsklenarova et al. 2014).the Cautires obsoletus species group, which was earlier given the rank of a genus, i.e., Bulenides Waterhouse, 1879, was studied earlier (Jiruskova & Bocak 2015) and all species of this species group are incorporated in the identification key.We delimit species using morphological diagnostic characters and we demonstrate the high species-level diversity of Cautires in the Malay mountain rainforests.

Material and methods
We had 159 specimens at our disposition from different localities in the Main range of Peninsular Malaysia, mainly from the Cameron Highlands in the Titiwangsa Mountains (Fig. 1).Although the area is quite small, about 1000 km 2 , it covers various ecosystems from the lowland tropical forests close to tapah (350 m a.s.l.), mid elevation forests in the area of kampong kuala Boh, ringlet and along the roads from Cameron Highlands to Gua Musang, Kuala Lipis, and Ipoh (600-1000 m a.s.l.), and high mountain and cloud forests in the highest elevations of the Mt.Brinchang, Beremban and Jasar (1500-2000 m a.s.l.).The specimens were collected mostly by sweeping of the low forest stratum and beating of vegetation.The material was preserved in 96% alcohol and each specimen was given a voucher number consisting of two letters and four-digit number.All specimens designated by these voucher numbers are deposited in the collection of the Laboratory of Molecular systematics, Palacký university, Olomouc, Czech Republic (LMBC).A piece of a metathoracic tissue of each specimen was deposited for future isolation of genomic DNA in the tissue collection of the same institution.
the study is based on adult males (Fig. 2) and, due to the absence of external morphological diagnostic characters and uniformity of female genitalia, we do not delimit any species when only females are available.Some females are included in the type series when they were collected simultaneously with the males and are phenotypically similar.As the identification of females is based on similarity to conspecific males, we do not provide detailed descriptions of females for each species.The differences in the structure of costae and ridges, the shape of the pronotum and colouration are variable in most species and do not provide reliable diagnostic characters.the density of transverse elytral costae depends on the body size of a specimen and colour patterns usually follow the most common co-mimetics in the locality and additionally the colouration partly depends on the altitude where the given population occurs.Generally, the mountain species are darker coloured or uniformly black (Fig. 79).
The tips of abdomen were placed in water to relax soft body parts for at least several hours and then transferred into hot 10% aqueous solution of potassium hydroxide for a short time depending on the level of sclerotization and the persistence of fat bodies and muscles.The phallus was removed from the abdominal sclerites, cleaned and photographed by a canon Eos 700D camera mounted on an Olympus SZX-16 binocular microscope.A scale in the eyepiece was used to take the measurements of the individual body parts described below.

Diagnosis
Cautires belongs to the subtribe cautirina in close relationships to Xylobanus (Lycidae: Metriorrhynchini), from which it can be distinguished by continuous larval terga and a simple, usually slender phallus with a pair of sickle-shaped thorns in the internal sac (sklenarova et al. 2014).Almost all oriental Cautires have the male antennae flabellate (Figs 7-20), some species have very short lamellae and the antenna is acutely serrate (Fig. 6).The female antennae are always serrate.Each elytron bears four primary and five secondary longitudinal costae (Figs 41-58) and numerous transverse costae connecting them.Cautires species have the lanceolate phallus with membranous internal sac bearing two sickle-shaped thorns at its base .
The latter study also redefined the limits of Xylobanus Waterhouse, 1879, which was originally defined by the absence of secondary costae.some Xylobanus have elytral costae similar to those of Cautires and adults of these species can be identified using the shape of male genitalia.The species group of C. obsoletus corresponds with the limits of Bulenides and these species differ in absence of lateral ridges in the pronotum.14.Antennomere 3 with lamella about 1.5 times longer than stem of antennomere, phallus relatively robust, pointed at apex, 6.7 times longer than wide at widest point (Fig. 78) ……C.tenebricus (kleine, 1930) -Antennomere 3 with lamella twice or more longer than stem of antennomere (Figs 10,12), if phallus pointed at apex then very slender, nine times longer than wide at widest point (Fig. 68) ………15

Etymology
The specific epithet alexae is a matronym in honour of Alex crampton-Platt, a colleague from the Natural History Museum in London.

Etymology
The specific epithet is proposed in honour of Paula Arribas, a colleague studying beetle soil communities.

Distribution
Peninsular Malaysia: Pahang.Cautires arribasae sp.nov. is known only from the mountain forests in the cameron Highlands.

Diagnosis
Cautires berembanensis sp.nov.belongs to a group of the species with the black body and very small eyes.The species is characteristic in the very wide, flat male antennomeres 3-10 (Fig. 6), which is unknown in other Malay species and in the extremely slender phallus (Fig. 62).

Etymology
The specific epithet refers to the type locality of the holotype.

Diagnosis
Cautires campestris sp.nov. is one of the species with a brightly coloured humeral part of the elytra, reddish pubescence on the disc of the pronotum and large eyes.this species has very long, slender antennal lamellae (Fig. 7), which resemble very closely those of the black coloured species C. jasarensis sp.nov.Additionally, C. campestris sp.nov.differs from other species in the robust phallus and the pronotum with vestigial postero-lateral ridges.

Etymology
The specific epithet refers to the lowland distribution of the species.

Distribution
Peninsular Malaysia: Perak, Kelantan.The species is widely distributed in low elevations of the Cameron Highlands region.

Etymology
The specific epithet refers to the abundance of the species.Altogether 52 specimens were identified in the available material and it makes C. communis sp.nov. the most common species in the cameron Highlands.

Distribution
Peninsular Malaysia: Pahang.Cautires communis sp.nov.was collected only in the highest part of the Cameron Highlands and does not occur on the northern slopes in lower elevations.

Diagnosis
Cautires griseus belongs to the group of species with a bright humeral part of the elytra (Fig. 47) and brown pubescence in the disc of the pronotum (Fig. 27).It differs from similarly coloured species in the length of antennal lamellae (Fig. 9) and in the relatively robust, shorter, parallel-sided phallus (Fig. 65).

Etymology
The specific epithet refers to the Mt.Jasar, the locality where a part of the type series was collected.

Distribution
Peninsular Malaysia: Pahang, Kelantan.This species is widely distributed in the Cameron Highlands.

Diagnosis
Cautires katarinae sp.nov. is similar to C. griseus in the reddish pubescence on the humeral part of the elytra and the shape of the pronotum.it differs in the shape of antennal lamellae (Figs 9,11).Additionally, C. katarinae sp.nov.has the robust phallus with the obtuse apex (Fig. 67).

Etymology
The specific epithet is in honour of Katerina Sklenarova, a colleague from the laboratory.

Description of the male
Body slender, mostly black, primary and secondary elytral costae with reddish pubescence, only posterior part of costae black (Fig. 49).Head small, eyes hemispherically prominent, large, eye diameter 1.29 times interocular distance.Antennae robust, flabellate, lamellae wide and flat (Fig. 11).Pronotum with 7 areolae, median areola well developed, marked by sharp ridges, median areola attached directly to basal margin of pronotum; anterior pronotal angles obtuse, lateral margins straight, lateral part of pronotum elevated, only slightly divergent, posterior angles prominent, but not acutely projected, pronotum with red pubescence (Fig. 29).Elytra parallel-sided, very slightly widened apically, primary and secondary costae well developed, transverse costae dense (Fig. 49).Phallus robust, widened from basal to apical fifth, slightly constricted in middle of widened part, widely rounded at apex (Fig. 67).

Distribution
Peninsular Malaysia: Kelantan.The species is known only from the type locality.

Etymology
The specific epithet kirstenae is a matronym in honour of kirsten Miller, a colleague from the Natural History Museum in London.

Distribution
Peninsular Malaysia: Pahang.The species is known only from the type locality.

Etymology
The specific epithet refers to the town Kota Tinggi, a place close to the locality where the paratype was collected.

Distribution
Peninsular Malaysia: Perak, Johor.Cautires kotatinggensis sp.nov. is one of a few widely distributed Cautires species in the Malay Peninsula.

Diagnosis
Cautires linardi sp.nov.belongs to the group with the uniformly black body and large eyes.This species has the characteristic shape of the pronotum with the very wide basal part and acutely projected posterior angles (Fig. 32).

Etymology
The specific epithet linardi is a patronym in honour of Benjamin Linard, a colleague from the Natural History Museum in London.

Etymology
The specific name is in honour of Michal Masek, a colleague from the laboratory.

Description of the male
Body uniformly black (Fig. 53).Head small, eyes hemispherically prominent, small, eye diameter 0.77 times interocular distance.Antennae flabellate, with lamella of antennomere 6 about twice longer than stem of antennomere (Fig. 15).Pronotum with shining disc and with 7 well developed areolae, median areola complete, well marked, attached directly to basal margin of pronotum; anterior angles obtuse, lateral margins concave, almost parallel-sided in anterior half of pronotum, lateral part of pronotum strongly elevated, posterior angles slender, acutely prominent (Fig. 33).Elytra apparently widened apically, primary and secondary costae well developed, transverse costae dense, slightly irregular (Fig. 53).Phallus very robust, slender only at basal third, apex rather obtuse (Fig. 71).

Etymology
The specific epithet refers to the Malay state Pahang where the holotype of C. pahangensis sp.nov.was collected.

Diagnosis
Cautires nervosus is one of the uniformly black coloured species (Figs 35,55).the species has extremely small male eyes, their diameter only 0.54 times the interocular distance, and a very short antennal lamella of antennomere 3 (Fig. 17). the phallus of C. nervosus is moderately wide (Fig. 73) and differs from the similar phalli of C. maseki sp. nov. and C. simillimus sp. nov. (Figs 71,76).

Distribution
Peninsular Malaysia: Pahang.Cautires nervosus is a very common species in the cameron Highlands area, but no specimens were recorded outside the Cameron Highlands plateau and adjacent mountain tops with elevation over 1400 m a.s.l.

Etymology
The specific name is in honour of Renata Bilkova, a colleague from the laboratory.

Distribution
Peninsular Malaysia: kelantan.Cautires renatae sp.nov. is known only from the type locality in the kelantan state.

Diagnosis
Cautires reverandi belongs to a group of species with a bright humeral part of the elytra (Fig. 57), a reddish pubescence on the pronotum (Fig. 37) and big eyes.It differs from the superficially similar species C. renatae sp.nov. in the shorter lamella of the antennomere 3

Distribution
Peninsular Malaysia: Perak, Pahang, kelantan.Cautires reverandi is a widely distributed species in the cameron Highlands region.

Remark
the holotype of C. reverandi is a female and the comparison with other species is limited to the general appearance.We identified a series of very similar specimens from several localities in the lowlands and lower mountain forests in the region, which we identified as C. reverandi.our association of the female type and the newly collected individual from Malay inland as the same species is additionally supported by a common occurrence in the region.kleine, 1926 Figs 20, 38, 58, 76 Cautires simillimus kleine, 1926: 187.

Diagnosis
Cautires simillimus belongs to a group of mountain species with a uniformly black body (Figs 38,58).this species resembles C. nervosus and C. maseki sp.nov. in the general appearance, but the males of C. simillimus have long and slender antennal lamellae (Fig. 20) and additionally they differ in the relatively robust, parallel-sided phallus (Fig. 76).

Type material
Holotype MALAYSIA: ♀, Pahang, Lubok Tamang, 3500 ft., 10 Jun.1923, H.M. Pendlebury (BMNH).A. et al., The genus Cautires in Malay mountain forests Bocak 2015).the total number of Cautires in the Malay Peninsula has reached 30 species (Fig. 79).The altitudinal distribution shows a very high diversity in the Main Range and twenty-one species have been reported from the humid and relatively cold mountain forests in the cameron Highlands plateau and the adjacent mountain tops with altitudes > 1000 m a.s.l.Only two species were collected in the intermediate elevations 600-1000 m a.s.l. and they overlap in distribution with the mountain species from elevations around 1000 m a.s.l.Additionally, six species were collected in the lowlands of the Malay Peninsula, i.e., elevations under 400 m a.s.l., and, finally, only a single species, C. indus, has a wide altitudinal distribution and this is the only species which was also reported from Sumatra.The proportion of lowland species is higher in the C. obsoletus species group as defined by Dudkova & Bocak (2010).The fauna of the mountain regions is mostly represented by species with a fully developed pattern of seven areolae in the pronotum.We noted that none of the species occurs in the wide span of different ecosystems from the lowlands to the high mountains and that a low number of species have been recorded from the intermediate to lower mountain elevations 600-800 m a.s.l.(Fig. 79).

JIRUSKOVA
Numerous black coloured species occur in the mountain forest at elevation over 1000 m a.s.l.(Fig. 79).Although some species with bright colour pattern have been collected in the mountain habitats, we noted that the black individuals dominated the mountain ecosystem and the brightly coloured individuals were only rarely collected from among them.the black species are restricted to elevations over 1000 m a.s.l. and we suggest that differences in mimicry patterns might play a role in the evolution of the mountain species.Membership in different aposematic rings has been found to be a factor limiting the gene flow in other organisms (e.g., Merrill et al. 2014;Twomey et al. 2014).
The favourable wet conditions are another factor which potentially contributes to the observed diversity in the higher elevations.The larvae of net-winged beetles have unique mandibles adapted for sucking liquids from decaying organic material (Bocak & Matsuda 2003) and they need very moist organic material to be able to feed throughout the year.the mountain area has a similar amount of precipitation to the lowlands west of the range, around 2600 mm per year, but further moisture occurs in mountain forests through condensation from clouds and lower evaporation.This is because the roughly 10ºC lower temperature results in the absence of a clear dry season in the high elevations (data from the www.worldclimate.comdatabase).the amount of organic debris on the soil surface is higher and the net-winged beetles are very common in these mountain localities.The larvae of Cautires have been collected from decaying twigs in the mountains of Sumatra (Bocak & Matsuda 2003) and sifted from soil surface wood debris in the Cameron Highland area (unpublished data).the comparison of a relatively high number of cautirina sequences reported in the previous study on phylogeny of Metriorrhynchini (sklenarova et al. 2013) indicates that the oriental species of Cautires have small ranges.The uniqueness of the Malay fauna was confirmed by the extensive search in the historical collections of the Oriental region in the museums of Paris, Warsaw and London, where the most important collections are deposited.We noted during this study that only a single species, C. indus, has been recorded in the Malay Peninsula and simultaneously in neighbouring sumatra and Borneo.The other species was reported from Malaysia and Java due to incorrect identification (Kleine 1926;C. congener).This finding agrees with the low dispersal propensity of net-winged beetles.In contrast with them, the fauna of many beetle families is similar on both sides of the shallow Malacca Strait which was dry for the substantial part of the Quaternary (Sathiamurthy & Voris 2006).The described high diversity, almost complete turnover between major regions and high level of endemism call for the protection of the unique faunas in the Malay mountains.

Fig. 1 .
Fig. 1. the sampled localities in the Malay Peninsula.A. the localities in the Malay Peninsula.B. Detailed map of sampled localities in the Cameron Highlands region.C. Habitats in the cameron Highlands mountain.

Fig. 79 .
Fig. 79. the altitudinal zonation of the Cautires species occurring in the Malay Peninsula.

Cautires from the Malay Peninsula
Peninsular Malaysia: Perak.Cautires alexae sp.nov. is known only from the type locality.
DiagnosisCautires arribasae sp.nov. is one of the species with a brightly coloured humeral part of elytra and black pronotum.thespeciesresembles C. alexae sp.nov.andC.kotatinggensis sp.nov. in general appearance and differs in the large eyes, the shape of the pronotum(Figs 21, 23, 31), and phallus (Figs 59, 61, 69).
The genus Cautires in Malay mountain forests Cautires jasarensis sp.nov. is similar to C. kirstenae sp.nov.Both species share the uniformly black body, pronotum and elytra, the relatively small, hemispherically prominent eyes and the long antennal lamellae(Figs 28, 30, 48, 50).C. kirstenae sp.nov.and the similarly coloured C. communis sp.nov.have a slender phallus pointed at the apex(Figs 64, 68), but the phallus of C. jasarensis sp.nov. is much wider in its apical third and its apical part is parallel-sided.the phallic apex of C. jasarensis sp.nov. is widely rounded in contrast with other species in the region (Fig. Cautires kirstenae sp.nov.belongs to the species with a uniformly black body.It is similar to C. communis sp.nov.and C. jasarensis sp.nov., but differs from C. communis sp.nov. in the long and slender male antennal lamellae (Figs 8, 12) and from C. jasarensis sp.nov. in the more slender phallus (Figs 66, 68).
Peninsular Malaysia: Pahang.JIRUSKOVA A. et al., The genus Cautires in Malay mountain forestsCautires maseki sp.nov. is one of numerous species with a uniformly black body.It is very similar to C. nervosus and C simillimus sp.nov. in general appearance and these species differ only in the shape of the phallus, which is extremely robust in C. maseki sp.nov.(Figs71,73, 76).
Cautires renatae sp.nov.resemblesC.reverandi in the bright humeral part of elytra and the reddish pubescence on the pronotum.Additionally, C. renatae sp.nov.has a different shape of the phallus (Figs 74-75).
and in the very wide phallus (Figs 74-75).