The taxonomy and diversity of Platerodrilus (Coleoptera, Lycidae) inferred from molecular data and morphology of adults and larvae

Abstract The Oriental neotenic net-winged beetles attracted attention of biologists due to conspicuous large-bodied females; nevertheless phylogenetic relationships remain contentious and only a few species are known in both the fully metamorphosed males and neotenic females. The phylogenetic analyses and morphology of larvae and adults provide data for investigation of relationships and species delineation. Platrilus Kazantsev, 2009, Platerodriloplesius Wittmer, 1944, and Falsocalochromus Pic, 1942 are synonymized to Platerodrilus Pic, 1921. Platrilus hirtus (Wittmer, 1938) and Pl. crassicornis (Pic, 1923) are transferred to Platerodrilus Pic, 1921. Platerodrilus hoiseni Wong, 1996 is proposed as a junior subjective synonym of Falsocalochromus ruficollis Pic, 1942. Platerodrilus is divided in three species-groups: P. paradoxus, P. major, and P. sinuatus groups defined based on the shape of genitalia and molecular phylogeny. The following species are described: Platerodrilus foliaceus sp. n., P. wongi sp. n. (P. paradoxus group); P. ngi sp. n., P. wittmeri (P. major group), P. ijenensis sp. n., P. luteus sp. n., P. maninjauensis sp. n., P. montanus sp. n., P. palawanensis sp. n., P. ranauensis sp. n., P. sibayakensis sp. n., P. sinabungensis sp. n., P. talamauensis sp. n., and P. tujuhensis sp. n. (P. sinuatus group). P. korinchiana robinsoni Blair, 1928 is elevated to the species rank as P. robinsoni Blair, 1928, stat. n. The conspecific semaphoronts are identified using molecular phylogeny for P. foliaceus sp. n., P. tujuhensis sp. n., P. montanus sp. n., P. maninjauensis sp. n.; additional female larvae are assigned to the species-groups. Diagnostic characters are illustrated and keys are provided for P. paradoxus and P. major groups.


Introduction
The platerodriline net-winged beetles are one of elateroid lineages with modified female morphology (Wong 1996, Masek et al. 2014. The adult males are fully metamorphosed . In contrast, females do not pupate and the sexually mature females remain larviform ("trilobite larvae", Figs 2-3, 32-43, Mjöberg 1925, Wong 1996, Bocak and Matsuda 2003. The taxonomic situation is complicated by the fact that Platerodrilus males and females have been observed in copula only twice (Mjöberg 1925, Wong 1996. The taxonomy of the neotenic lineages has quite short history despite the fact that the trilobite larvae were first time described in the 19 th century (Perty 1831, Candèze 1861). Platerodrilus Pic, 1921 was proposed for five species and although compared with Plateros Bourgeois, 1879 (Lycidae), the new taxon was placed in the distantly related Drilidae (now Drilini in Elateridae; Kundrata and Bocak 2011). Mjöberg (1925) erected Duliticola, described both sexes of D. paradoxa Mjöberg, 1925 and discussed the possibility to establish Duliticolinae in Lycidae. Only recently the trilobite larvae attracted further students. Wong (1996) reported another case of a male and a female observed in copula and studied most M. Pic's types deposited in the Paris Museum, but his work remained unpublished (Wong 1998). Kazantsev (2002) described the subfamily Duliticolinae, but the name is unavailable and replaced by Miniduliticolinae (Kazantsev 2005). Kazantsev (2002) designated the type species of Platerodrilus, considered Duliticola as its junior synonym and later described a new genus Platrilus Kazantsev, 2009 which corresponds to Platerodrilus sensu Wong (1998). The subgenus Platerodriloplesius Wittmer, 1941 was elevated to the genus rank by Kazantsev (2002). These taxa are based on flabellate antennae (Platerodriloplesius) or the unique shape of male genitalia (Platrilus) and their relationships have remained contentious.
The DNA data represent an independent source of information for species delineation (Vuataz et al. 2011) and for identification of the conspecific semaphoronts (Ahrens et al. 2007). We present the molecular phylogeny of Platerodrilus and compare the results with morphology of adults and larvae to solve taxonomy of Platerodrilus. As a result, we describe new species and discuss their relationships.

Morphological taxonomy
Adult males and female larvae were used for morphological descriptions. A part of specimens used for morphological study was sequenced and labelled with the Gen-Bank voucher numbers in the format UPOL + six-letter/number code and the status of all type specimens were designated with red labels (ICZN 1999). The codes are listed in examined material (Table 1). A. T. C. Wong studied many species in mid 1990's, but the types have not yet been returned to the Paris museum. Therefore, we redescribe only species, which are currently available in the types or are described as new. Other species were redescribed by Wong (1998) and Kazantsev (2009). All morphological measurements were taken using the ocular grid of an Olympus SZX-16 binocular microscope. Abbreviations and depositories. Descriptions: BL-length of body; WH-width at humeri; PL-length of pronotum; PW-width of pronotum; Ediam-maximum eye diameter; Edist-minimum interocular distance in frontal part of cranium.

Sequence handling and phylogenetic analyses
Sequences were edited using the Sequencher 4.8 software package (Gene Codes Corp.). The rrnL mtDNA fragment was aligned using ClustalW 1.83 (Thompson et al. 1994 (Stamatakis et al. 2005) and the bootstrap support of branches (BS) assessed by analyzing 100 pseudoreplicates. All genes and codon positions in the protein coding fragments were partitioned. The model was proposed by jModelTest 2.1.2 (Posada 2008). The dataset was additionally analyzed using MrBayes 3.2.2 (Huelsenbeck 2000). The MCMC was set for independent variability of parameters in individual coding and non-coding genes under the GTR+I+G model. Two runs, each with four chains ran simultaneously for 40×10 6 generations, with trees being sampled every 1000 th generation, all fragments were partitioned and unlinked. The first 6-9×10 6 trees were discarded as burnin and posterior probabilities (PP) at nodes were determined from the remaining trees. The ultrametric tree was produced from the tree depicted in Fig. 1 using r8s software (Sanderson 2002) and the GMYC method as implemented in SPLITS (http:// www.rforge.r-project.org/projects/splits/) was applied to the ultrametric tree.

Sequence variation and phylogeny
The DNA sequences of rrnL were produced for 73 specimens. The dataset of aligned rrnL sequences contained 530-723 homologous positions depending on the applied alignment procedure; 253-267 characters were parsimony informative. The topologies produced from BlastAlign, Muscle and Clustal alignments analyzed under maximum likelihood method and Bayesian inference identified the same strongly supported principal clades of Lyropaeinae and although topologies differed somewhat with respect to the deeper nodes of Miniduliticolini, all analyses recovered Pendola, Macrolibnetis, Horakiella and related taxa as deeper splits of Miniduliticolini and Platerodrilus as a terminal lineage (Fig. 1). One terminal, Platerodrilus sp. 000L01 was recovered outside Lyropaeinae and we consider its position as an artefact of the single marker analysis. The species was found in relationships to another Platerodrilus in the six-gene analysis of Lycidae . Therefore this taxon is not considered in the further discussion.
The P. paradoxus and P. major clades were well supported in all analyses except by analysis of the Clustal alignment (BS 100%, PP 52-100% and BS 97-99%, PP 52-100%, respectively). The P. sinuatus group (including the nested P. major group) obtained much lower support (BS 46-56%, PP < 89%). The species level clusters and relationships of closely related species were regularly well supported (Fig. 1).
The GMYC analysis of the normalized tree was used as an independent test for morphology based delineation of species. The analysis suggested the clusters designated as P. tujuhensis and P. maninjauensis (uncorrected genetic distance 1.4%) as separate species and these are well supported also by morphological differences (see Taxonomy). Similarly, two separate species were inferred for two specimens of P. sibayakensis (uncorrected genetic distance 0.8%) and these do not differ in any morphological character and were collected in the same region.

DNA identification of immature stages
The origin of large-bodied neotenic larvae was recovered in three unrelated lineages: Lyropaeus, Macrolibnetis depressus + unidentified species from India and Platerodrilus (Fig. 1). Males and female larvae of four species, i.e. P. foliaceus, P. maninjauensis, P. montanus and P. tujuhensis clustered with conspecific males in clades with very high bootstrap support. Additionally, a number of larvae was assigned to the species groups in relationships to the previously described species (Fig. 1). We found that the species of the P. paradoxus clade share pronotum without glabrous prominent tubercles (Figs 1,34,40). Similarly, the species of the P. sinuatus group from continental Asia ( Fig. 1) have smooth terga (VP2304, VP2311). The glabrous tubercles in the discs of the thoracic terga are present only in the lineage of Sumatran and Malay species of the P. sinuatus group ( Fig. 1; terminals VP2308, VP2302, VP2307, VP0047 etc.). The robust, vermiform larva ( Fig. 43) clustered with species of the P. major clade (Fig. 1).

Supergeneric classification of Platerodrilus and related genera.
The results confirm that Lyropaeini (i.e., Lyropaeus Waterhouse, 1878 sensu lato) is an independent lineage with the large-bodied neotenic females and Platerodrilus belong to a sister-clade of Lyropaeini along with Macrolibnetis, Horakiella, and Pendola (Fig. 1). Most of these genera are also known only from males but no large bodied female has been assigned to them and their females are probably larviform but similar in body size to males. The only miniduliticoline taxon with the large-bodied female except Platerodrilus is Macrolibnetis (Levkanicova and Bocak 2009).
The subfamiliar and tribal classification of Platerodrilus and related genera has been ambiguous. Mjöberg (1925) used the name Duliticolinae, but stated that the formal description should be postponed. Therefore, Duliticolinae Mjöberg, 1925 is an unavailable name. Kazantsev (2002) erected subfamily Duliticolinae without any description and with type genus Platerodrilus as a single genus classified in the new tribe, when he considered Duliticola as a junior synonym. According to the articles 13.1 and Articles 11.7.1.1 and 64 (ICZN 1999) the name Duliticolinae Kazantsev, 2002is unavailable. Kazantsev (2002 further proposed the name Miniduliticolini for Miniduliticola Kazantsev 2002, but the description is uninformative: "The hypothesized apomorphies of the genus Miniduliticola gen. n., particularly glabrous elytra with no trace of longitudinal costae or tubercles support the erection of a new tribe". The single type specimen of Miniduliticola is damaged and there is no information available on male genitalia. The name Miniduliticolini Kazantsev, 2002 became the oldest available name for a clade which is recovered as a sister clade to Lyropaeini Bocak and Bocakova, 1989 (Fig. 1). Kazantsev (2005) proposed Platerodrilini to replace Duliticolini Kazantsev, 2002. In this case, he provided description of the new taxon: "The Platerodrilini tr. n. is tentatively included in Miniduliticolinae. The hypothesized apomorphy of the new tribe distinguishing it from Miniduliticolini is the reticulated elytra." (Kazantsev 2005). Therefore, we have two available names for supergeneric taxa, one based on a single damaged specimen bearing characters correlated with small body (i.e. simplified structures, Bocak et al. 2014) and the second name without any delineation, based on Platerodrilus, which represents a crown branch in the current molecular phylogeny. As the position of Miniduliticolini was considered tentative in Duliticolinae sensu Kazantsev (2002) and also Platerodrilini were tentatively placed in Miniduliticolini (Kazantsev 2002), the names are not connected to any phylogenetic hypothesis to define their limits and relationships of Miniduliticola remain unknown. Therefore, we propose to use Miniduliticolini for designation of the whole clade in a sister position to Lyropaeini including Platerodrilus, Pendola, Horakiella and Macrolibnetis (Fig. 1). If Miniduliticolini belong to any other lineage, the sister-group to Lyropaeini would be designated as Platerodrilini.
The other Miniduliticolini with large-bodied neotenic females form a clade designated as Platerodrilus in Fig. 1. The deepest split of Platerodrilus consists of a clade of P. curtus, P. foliaceus and several unidentified larvae . Their male genitalia (Figs 44-47) resemble those of P. paradoxus (see Kazantsev 2009) and the larvae do not have glabrous tubercles in the disc of the pronotum. These characters place P. paradoxus (type species of Duliticola) in the clade designated as P. paradoxus group in Fig.  1. Further, based on morphology, two species P. svetae and P. wongi (Fig. 5) are placed here. This group is a monophyletic lineage in Fig. 1, but we do not reinstate the name Duliticola Mjöberg, 1925 as the present sampling is limited and the genus cannot be recognized using external characters.
The sister clade to the P. paradoxus clade contains Platerodrilus species with two types of male genitalia: (a) the phallus with short, densely pubescent parameres (Figs 48-51) and (b) the phallus slender, curved, parameres with long membranous apical process . We designate these groups as P. major and P. sinuatus groups (Fig. 1). The P. major group (Figs 1,17,30,(48)(49)(50)(51) contains species placed in Platrilus by Kazantsev (2009). This lineage represents a crown clade within P. sinuatus group (Fig. 1). This assemblage was designated as Platerodrilus sensu Wong (1998), when P. major Pic, 1921 was proposed as a type genus of Platerodrilus and D. paradoxa Mjöberg, 1925 for Duliticola to keep both names valid (invalid designations in the unpublished manuscript by Wong 1998). Kazantsev (2002) designated P. sinuatus Pic, 1921 as a type species of Platerodrilus and considered as Duliticola a junior synonym of Platerodrilus. Subsequently, he erected a separate genus Platrilus Kazantsev, 2009. As a subordinate lineage, Platrilus cannot be accepted in classification and is proposed to be a junior synonym of Platerodrilus.
The P. sinuatus group contains species from continental Asia, which form a deep split (terminals VP2304, VP2311) and further a group of species from the Sundaland and Palawan (Fig. 1). Larvae from continental Asia do not have any tubercles in the thoracic terga, similarly to the P. paradoxus and P. major group, only the species from Sumatra, Java and Malay Peninsula have the glabrous tubercles both in the disc and posterior margins of thoracic terga 39). The males of these species can be assigned to continental or Sundaland lineages only with DNA data. Therefore, we propose to group them in the P. sinuatus group despite paraphyly of the assemblage.
Further two genus-group names were proposed for species now placed in Platerodrilus. Platerodriloplesius was erected for taxa with flabellate male antennae (Wittmer 1944). The male genitalia of Platerodrilus bicolor (Wittmer, 1941) (type species of Platerodriloplesius) resemble those of P. paradoxus. In contrast, genitalia of P. palawanensis sp. n. (Figs 69-70) and P. borneensis (Wittmer, 1966) (both species having the flabellate antennae) indicate their relationships to P. sinuatus group (Figs 52-72). Morphology of genitalia indicate that the species classified in Platerodriloplesius belong to different clades and Platerodriloplesius in Kazantsev's sense is a polyphyletic typological assemblage based on a highly variable morphology of male antennae, which might be used for pheromone communication, and therefore their surface is expanded by lamellae to house a higher number of olfactory sensors. As the type species of Platerodriloplesius belongs to the P. paradoxus group, Platerodriloplesius is a junior synonym of Duliticola and Platerodrilus. Pic (1942) described Falsocalochromus in the supposed relationships to Calochromus Guérin-Méneville, 1833. The described species Falsocalochromus ruficollis Pic, 1942 is conspecific with Duliticola hoiseni Wong, 1996 from the P. sinuatus group and the Falsocalochromus is a junior synonym of Platerodrilus.
To sum up, we propose to consider Duliticola, Platerodriloplesius, Platrilus and Falsocalochromus to be junior synonyms of Platerodrilus. Platerodriloplesius represents a polyphyletic assemblage and Platrilus is a terminal branch supported by unique apomorphies rendering Platerodrilus in a paraphylum. As these taxa cannot be assigned to species groups without dissection of male genitalia, the proposed generic classification results in a definition of an easily recognisable monophyletic assemblage.
Rapid morphological divergence in male genitalia is widespread and results largely from sexual selection (Eberhard 2010). Therefore, delineations based on highly divergent genital morphology can lead to proposal of genus-rank taxa when the group of species sharing divergent genitalia represents only a terminal subclade. The molecular phylogeny revealed such pattern in broadly defined Platerodrilus, where three types of male genitalia are encountered. On the other hand, we can see low divergence in genitalia within Platerodrilus subclades, e.g., the P. sinuatus group. The diverging populations of Platerodrilus are in allopatry and the reinforcement of the reproductive barriers cannot take place. Probably as a result, the male genitalia are similar within species groups consisting of allopatrically distributed species (Wong 1998 (Bocak 2002).
Female mature larva. Diagnosis. Body shape characteristic ("trilobite larva" Figs 32-43). Two body types are present: the flat, wide (Figs 32-42) and robust, vermiform (Fig. 43). Although different in general appearance these larvae share common diagnostic characters: the fossa antennalis closed, separated from the mouth-parts by pleurostoma (the pleurostoma absent from other lycids); slender, longitudinal sclerite present ventrally of pleurostoma; mala sclerotized. The apical antennomere with several peg-like processes. The complex, oval meso-and metathoracic spiracles are cribriform, the sieve plate with multiple openings. They are situated in large depressions. Similar larvae of Lyropaeus differ in the shape of the apical antennomere and both Macrolibnetis and Lyropaeus do not have spiracular cavities in abdominal segments (Masek et al. 2014).
Description. Body wide, considerably flattened due to extensively projected lateral plates (Figs 32-41) or slender with postero-lateral processes (Fig. 43), usually dark brown, cryptically coloured, some species aposematically coloured with brightly coloured patches. Head prolonged, rounded anteriorly; epicranium consists of dorsal and pleural plates, membranous between plates. Complete fossa antennalis dorsally limited by epicranium, ventrally by sclerotized pleurostoma. Longitudinal sclerite situated ventrally of pleurostoma. Basal antennomere very short, apical antennomere with several peg-like processes ventrally and more extensive, sclerotized area dorsally. Mala sclerotized, with peg-like process. Cervical membrane extensive, with pigmented patches postero-ventrally. Pronotum trapezoid, terga with considerably widened lateral plates and sometimes with tubercles at posterior margin. Prosternum prolonged, episterna extensive, attached to prosternum. Extensive spiracular plates with spiracular openings at margin and bottom of extensive cavity in both, meso-and metathorax. Legs slender, relatively long, trochanters divided in two parts. Abdomen with large lateral processes, spiracular openings on margin and bottom of cavities in segments A1-A8. Sterna A1-A8 with slender postero-lateral processes, upper pleurites extensive, with similar process at outer posterior angle. Lower pleurites very small, with short process only in segments A3-A8. Segment A9 widest at apex, with short, fixed urogomphi (Figs 35-40, 43).
Remark. Sexually mature larviform females observed only by Mjöberg (1925) and Wong (1996) were not available to us. The collected larvae did not pass the final ecdysis and their maturity is supposed on the basis of their body length. Only several lower instar larvae were collected and they differ from later instars in shorter and partly missing processes and absence of spiracular cavities.
Biology. The information on biology was given by Wong (1996) and Bocak and Matsuda (2003).
Distribution. Most species are known from Borneo and the Philippines, only P. wongi sp. n. occurs in Sumatra.

Platerodrilus paradoxus
Diagnosis. P. paradoxus belongs to a group of Bornean species with robust and long parameres. The male of P. paradoxus resembles P. foliaceus but differs in the slender apex of parameres. Additionally these species differ in larval morphology (Figs 34, 40).
Female larva. Body flat and wide (Fig. 34), pronotum parallel-sided at base, then gradually tapering to front, triangular, without any glabrous tubercles in disc, only small tubercles in middle part of posterior margins of thoracic segments, in middle of anterior pronotal margin four subequal tubercles; mesothorax strongly transverse, with rounded lateral margins and straight posterior margin, posterior angles obtuse, metathorax similar in shape with more acutely projected posterior angles. Abdomen with short, robust lateral processes.
Measurements. Male. BL 6.9 mm, PL 1.0 mm, PW Diagnosis. P. foliaceus belongs to the P. paradoxus group and the male resembles P. paradoxus in general appearance. P. foliaceus differs in the rounded apex of parameres (Figs 46-47). The female larvae of P. foliaceus are very flat and have much slenderer lateral processes of abdominal segments than P. paradoxus (Figs 34, 40).
Female larva. Body extremely flat and wide (Fig. 40), pronotum triangular, without any glabrous tubercles, in middle of anterior margin four subequal tubercles; mesothorax strongly transverse, with rounded lateral margins and moderately projected posterior angles, metathorax similar in shape with more acutely projected posterior margins. Abdomen with very slender and long lateral processes.
Distribution. Indonesia: Kalimantan. Known only from the type locality. Etymology. The specific epithet refers to the flat body shape of the female larva. Remark. The males and female larvae were identified as conspecific on the basis of highly similar sequences of rrnL (Fig. 1). Diagnosis. P. wongi is a single species of the P. paradoxus group occurring in Sumatra. It resembles P. curtus from the Philippines in the uniformly yellow elytra, but has relatively shorter parameres (Figs 44-45).
Distribution. Indonesia: Northern Sumatra. Etymology. The specific epithet is a patronym in honour of Alvin T. C. Wong.
The key to identification of males from the P. paradoxus species group Whole elytra yellow (Fig. 5)  * We failed to find any distinguishing character between P. svetae and P. piceicollis. The type of P. svetae is deposited in a private collection and unavailable for study.

Species group Platerodrilus major Pic, 1921
Diagnosis. The species group P. major is a monophyletic assemblage representing a terminal branch, which includes the species placed in Platrilus Kazantsev, 2009 and it is represented in the current analysis by P. major and P. ngi (Fig. 1). The group is characterized by the short and setose parameres without long membranous apical processes (Figs 48-51). The following species are placed here: P. atronotatus Pic, 1943, P. crassicornis Pic, 1923, P. hirtus Wittmer, 1938, P. major Pic, 1921, P. ngi sp. n. and P. wittmeri sp. n. The species described by M. Pic were redescribed by Wong (1998). T. C. Wong 1993 (ZRCS); 1 spec., Singapore, Sime Road, C. Lee (ZRCS, #6.20969, 1993(ZRCS, #6.20969, .7277, 1993. Diagnosis. P. ngi is the only representative of the P. major group known from Singapore and Tioman. It differs in dark red colouration of the pronotum and humeral two thirds of elytra from P. atronotatus from the Malay Peninsula. P. atronotatus has the black pronotum. Additionally, the phallus of P. atronotatus is slender and antennomeres 3 and 4 short and much wider.

Platerodrilus ngi
Description. Male. Body small, dark brown to black, head, prothorax, mesoscutellum and basal two thirds of elytra dark red; whole body with dense, short, pubescence. Head small, including eyes slightly wider than frontal margin of pronotum. Eyes hemispherically prominent, frontal interocular distance 1.8 times eye diameter. Antennae robust at base, compressed, reaching two thirds of elytral length, antennomere 3 0.6 times antennomere 2, antennomere 3 as long as wide at apex. Pronotum flat, 1.7 times wider than long at midline. Anterior margin almost straight, anterior angles sharply marked, posterior margin bisinuate. Elytra slightly wider posteriorly, elytra 2.8 times longer than width at humeri; only slightly widened posteriorly, elytral costae conspicuous. Legs compressed, densely pubescent. Male genitalia with straight phallus and setose parameres, short phallobase slightly shorter than parameres.
Distribution. Singapore, Malaysia: Pahang. Biology and female specimens collected in Singapore were reported by Lok (2008).
Etymology. The species name is a patronym in honour of Peter Ng. Diagnosis. P. wittmeri is the only bicoloured species from the P. major group in Java. It resembles P. major from Northern Sumatra in colouration but differs in the shorter phallobase (Figs 48-49, 50-51).
Distribution. Indonesia: Java. Etymology. The specific epithet is a patronym in honour of the late W. Wittmer, who donated the specimen to the senior author in 1992.

5
The expanded base of phallus in lateral view mostly hidden by parameres, phallobase deeply emarginate basally, elytra black apically ......... P. major Pic -The expanded base of phallus in lateral view exposed, considerably widened, phallobase shallowly emarginate basally, elytra testaceous ..P. hirtus Wittmer Species group Platerodrilus sinuatus Pic, 1921 Diagnosis. The group P. sinuatus is a paraphyletic assemblage consisting of P. luteus, the Indo-Burmese species (represented in the analyzed dataset by female larvae VP2304, VP2311), P. palawanensis from Palawan, P. indicus from Assam and Nepal and the terminal lineage of Platerodrilus from Sundaland (Figs 1-2). All species have a long, slender, considerably curved phallus and short parameres with the membranous apical process (Figs 52-72). The following species are placed in this species group: P. angustatus Pic, 1921, P. apicalis Pic, 1936, P. atricolor Pic, 1938, P. corporaali Pic, 1921, P. grootaerti Kazantsev, 2009, P. holynskae Kazantsev, 2009, P. inapicalis Pic, 1937, P. indicus Wittmer, 1966, P. luteus sp. n., P. maninjauensis sp. n., P. montanus sp. n., P. palawanensis sp. n., P. ranauensis sp. n., P. reductus Pic, 1926, P. rotundicollis Wittmer, 1938, P. ruficollis Pic, 1942, P. rufus Pic, 1924, P. sinuatus Pic, 1921, P. talamauensis sp. n., P. tujuhensis sp. n., P. sibayakensis sp. n. and P. sinabungensis sp. n. The female larvae of species occurring in continental Asia north of the Isthmus of Kra have terga without glabrous tubercles similarly to the species of the P. paradoxus clade. The group of species from the Malay Peninsula, Sumatra and Java are characterized by larvae with glabrous tubercles in thoracic terga (Figs 1, 32-33, 39, 41). The male genitalia are similar in the shape of the basal part of the phallus and phallobase. The minute differences are difficult to describe in a form of the identification key and the DNA data were used for confirmation of the species delineation in several cases. Diagnosis. P. ijenensis is the only Javanese species of P. sinuatus group with bicoloured elytra. It resembles in colour pattern the Sumatran species P. corporaali, which differs in the reddish coloured head and basal antennomeres, and the very short antennomere 3.
Female larva. Body flat, wide (Fig. 32), pronotum triangular, with two glabrous rounded tubercles postero-laterally, another two tubercles in middle of anterior margin; mesothorax strongly transverse, with rounded lateral margins and weakly projected posterior angles, laterally with four tubercles, upper rounded, lower transverse, metathorax similar in shape with more acutely projected posterior margins. Abdominal segments with slender and long lateral processes.
Female larva. Body flat, wide (Fig. 33), pronotum triangular, without glabrous tubercles except two tubercles in middle of posterior margin; mesothorax strongly transverse, with rounded lateral margins and weakly projected posterior angles, laterally with four tubercles, upper rounded, lower only slightly transverse, metathorax similar in shape with more acutely projected posterior margins. Abdominal segments with slender and long lateral processes.
Description. Body medium-sized, dark brown to black, only pronotum, mesoscutellum and humeral two thirds of elytra orange; apical third of elytra and two thirds of elytral suture dark brown to black. Head small, including eyes apparently narrower than frontal margin of pronotum, antennal tubercles robust, deeply separated. Eyes hemispherically prominent, eye diameter 1.9 times frontal interocular distance. Antennae flabellate, antennomere 3 with long process, pubescent, length of antennomere 3 1.6 times antennomere 2. Pronotum strongly transverse, 1.5 times wider than long at midline, anterior margin straight, with prominent anterior angles, lateral margins almost straight, posterior margin bisinuate, surface of disc mat, finely punctuate, with dense short pubescence. Elytra 2.9 times longer than width at humeri, elytra almost parallel-sided; slightly widened posteriorly, widest at apical fourth, elytral costae inconspicuous. Legs compressed, with dense pubescence. Male genitalia with curved phallus, short rounded parameres bearing slender membranous processes; phallobase wide, deeply emarginate (Figs 69-70 Diagnosis. P. ranauensis was found as a sister species to P. talamauensis (Fig. 1) and these species differ in the extent and shape of the orange part of elytra and in the shape of the posterior margin of phallobase (Figs 54-55).
Description. Body medium-sized, dark brown to black, only pronotum testaceous to brown and basal quarter of elytra orange (Fig. 9). Head small, including eyes slightly narrower than frontal margin of pronotum, antennal tubercles small. Eyes hemispherically prominent, eye diameter 2.3 times frontal interocular distance. Antennae compressed, pubescent, length of antennomere 3 1.1 times antennomere 2. Pronotum transverse, 1.7 times wider than long at midline, anterior margin widely rounded, semicircular, without prominent anterior angles, posterior margin of pronotum bisinuate, surface of disc glabrous, with sparse long pubescence (Fig. 24). Elytra almost parallel-sided, 3.0 times longer than width at humeri; slightly widened posteriorly, widest at apical fourth. Elytral costae inconspicuous. Legs compressed, with dense pubescence. Male genitalia with short rounded parameres bearing slender membranous processes; phallus curved, phallobase wide, deeply emarginate (Figs 54-55 (Fig. 1) and they share the pronotum with acutely projected posterior angles. P. sibayakensis differs in the 4.1 times longer antennomere 4 than its width in the middle and the more robust phallus tapering gradually from the base to apex (Figs 71-72). Diagnosis. P. talamauensis and P. ranauensis are closely related (Fig. 1) and they differ in the extent and shape of the orange part of the elytra (Figs 9, 15) and in the shape of posterior margin of phallobase (Figs 52-55).
Distribution. Indonesia: Sumatra. Etymology. The specific epithet refers to the type locality of the holotype. Diagnosis. P. tujuhensis resembles in the uniformly light coloured head, pronotum and elytra P. robinsoni, which differs in the more robust basal part of the phallus. The molecular phylogeny suggests the sister relationships of P. maninjauensis and P. tujuhensis. These species differ in colouration (Figs 7, 12) and the shape of the phallus and phallobase (Figs 56-57, 60-61). The female larvae of both species are similar and differ only in the relative size of mesonotal tubercles, which are smaller in P. tujuhensis.
Female larva. Body flat, wide, dark brown, only margins of tergites lighter, pronotum triangular (Fig. 41), with two glabrous rounded tubercles postero-laterally, another two tubercles in middle of anterior margin; mesothorax strongly transverse, with rounded lateral margins and weakly projected posterior angles, laterally with four tubercles, upper rounded, lower transverse, metathorax similar in shape with more acutely projected posterior margins. Abdominal segments with slender and long lateral processes.
Distribution. Indonesia: Sumatra. Etymology. The specific epithet refers to the locality of the paratype.

Platerodrilus ruficollis
Remark. Wong (1996) described and illustrated Duliticola hoiseni. During the recent search in the Paris Museum we found that Pic (1942) described the same species as Falsocalochromus ruficollis and placed in the relationships with Calochromus despite that fact that the species perfectly fits in his own concept of Platerodrilus. Therefore, we propose D. hoiseni as a junior subjective synonym of P. ruficollis.
Remark. P. testaceicollis was placed in Platerodrilus by Kazantsev, 2009, but the abdomen of the type is missing and the species cannot be placed in any species group unless further specimen is available. The redescription was given by Wong (1998).

Duliticola javanica Kemner, 1928: 136.
Remark. The type series contains just female larvae judging from the illustrations might include two species. The adult is unknown.