Two new species of Paraneseuthia are described from peninsular Malaysia: P. joeparkeri sp. n. from Bukit Larut (Maxwell Hill) and P. titiwangsana sp. n. from the Genting Highlands. The new species are morphologically allied to species known so far only from Sumatra; they all share emarginate apex of the aedeagus bordered at each side by a subtriangular projection and a pair of setae. This is the first record of this eutheiine genus from the Malay Peninsula and extends the known diversity of Paraneseuthia species within the historical Sundaland area.
Four new species of Cephennomicrus are described from Malaysia: C. curvidens sp. n., C. gentingensis sp. n. (both from the Genting Highlands, West Malaysia), C. santubongensis sp. n. and C. muluensis sp. n. (both from Sarawak, East Malaysia). Male genitalia of all new taxa are illustrated and diagnostic characters are discussed.
A new species of the Oriental genus Elacatophora, E. euconnoides sp. n., is described from the Cameron Highlands, West Malaysia. Diagnostic characters, including the male genitalia, are illustrated and discussed. A new case of subjective synonymy was discovered: Elacatophora minae (Makhan & Ezzatpanah, 2011) is placed as syn. n. of E. soesilae (Makhan & Ezzatpanah, 2011).
A new species of Clidicini ant-like stone beetles, Clidicus mawarensis sp. n., is described and illustrated. The holotype male was collected in East Malaysia (Borneo: Sabah); the new species belongs to a group of large-bodied Clidicus, and shows similarities to C. ganglbaueri Reitter; the male has unusually complex structures of the aedeagal apical region.
Six new species of the cephenniine genus Hlavaciellus Jałoszyński are described: H. cincinnalis sp. n. (Malaysia: Sabah); H. carinatus sp. n. (Malaysia: Pahang); H. microtuberculatus sp. n. (Malaysia: Pahang); H. diversipilosus sp. n. (Malaysia: Pahang); H. concavus sp. n. (Indonesia: Sumatra); and H. sumatranus sp. n. (Indonesia: Sumatra). An updated key to identification of males of all nominal species of Hlavaciellus is given.
Clidicus Laporte, 1832 currently comprises 27 species distributed in India (Karnataka, Tamil Nadu), Sri Lanka, Indonesia (Java, Kalimantan, Sumatra), Malaysia (Sabah, Sarawak), Laos, Vietnam, the Philippines (Mindanao), China (Hainan) and Australia (Queensland). Some species have conspicuously large adults reaching 8.5 mm, and they represent the largest known Scydmaeninae. Species of Clidicus were relatively poorly known until recently, when Orousset (2014) revised a large portion of this genus and described several new species. Other major studies include Besuchet (1971), who described Sri Lankan species, Jałoszyński et al. (2003) who recorded four new species from Vietnam and Laos, Jałoszyński (2009) with the first description of a Philippine species, and Zhou Li (2015), who discovered the first species in China. Another new species, representing the second Clidicus occurring in the Philippines, is described below.
Loeblites Franz, 1986 is a genus of Glandulariini with adults sharing a very similar body form and most taxonomically important structures with Syndicus Motschulsky, 1851. One of the most conspicuous differences between these genera is the antennal structure. In Syndicus, the antennomere XI is strongly reduced, much shorter than X and lacks the basal stalk, so that the two terminal antennomeres are compactly assembled. They either form one oval structure that appears as a single antennomere because the base of subconical antennomere XI is as broad as apex of X (Syndicus s. str.) or the antennomere XI forms a distinct small 'papilla' on top of X (subgen. Semisyndicus Jałoszyński, 2004) because the base of antennomere XI is much narrower than apex of X. Adults of Loeblites have unmodified antennae, with the antennomere XI strongly elongate and with a narrow basal stalk; additionally the antennae are strikingly slender, nearly filiform. Morphological structures of both genera were described and illustrated by Jałoszyński (2004, 2005). While Syndicus is species-rich, often abundant in leaf litter and under bark in subtropical forests (Jałoszyński 2004, 2006, 2008, 2009, 2011, 2014; Jałoszyński Nomura 2006; Yin Li 2015; Yin et al. 2014; Yin Zhou 2016; Zhou Yin 2017), and broadly distributed from southeastern Australia, through Southeast Asia, Yunnan (China) and Ryukyus (Japan), up to Sri Lanka, India and the Himalayas, Loeblites comprises merely four species known to occur in Malaysia, Thailand and China (Jałoszyński 2005; Zhou Li 2015). Loeblites mastigicornis Franz, 1986 is known to occur in Chiang Mai (northern Thailand), L. sabahensis Franz, 1992 and L. minor Jałoszyński, 2005 in Sabah (northern Borneo), and L. chinensis Zhou Li, 2015 in Yunnan (southwest China). Two females representing an undescribed species were also recorded from Yunnan by Zhou Li (2015). Specimens of this interesting genus are found rarely, in small numbers and they are typically sifted from leaf litter in subtropical forests.
The 'Cephennomicrus group' of Cephenniini includes nine genera distributed mostly in SE Asia (but with some species known also from other continents, except for the Americas). Four new Oriental species are described: Cephennococcus penangensis sp. n. (W Malaysia), Cephennomicrus matangensis sp. n. (E Malaysia), Cephennomicrus selangorensis sp. n. (E Malaysia), and Trurlia nova sp. n. (E Malaysia). Cephennomicrus selangorensis is unique in having the pronotum in both sexes with broad lateral impressions demarcated from the disc by a sharp ridge, a modification slightly similar to that of only one (Australian) congener.
The genus Marcepania is a sole member of the tribe Marcepaniini, known to occur in SE Asia. The five hitherto described species inhabit the Malay Peninsula and Borneo. The first species discovered in the Philippines, Marcepania princesa sp. n. is described here, based on a male specimen found on the island of Palawan. It is most similar to its geographically closest relative, M. elongata of northern Borneo.
The glandulariine genus Siamites is amongst the rarest Oriental ant-like stone beetles. To date, only three species have been known, distributed in Thailand and Vietnam. A new species, S. sarawakensis sp. n. is described here, based on a male specimen collected in Sarawak, East Malaysia. This finding extends the known range of Siamites over 1200 km southeastward.
Four new species of the rare glandulariine genus Siamites Franz are described: S. langkatensis sp. n. (Indonesia); S. thantonus sp. n. (Thailand); S. sumatrensis sp. n. (Indonesia); and S. sabahensis sp. n. (E Malaysia). The Indonesian species represent the first records of Siamites on Sumatra, and the Malay species is the first Siamites known to occur in Sabah; the number of nominal Siamites species increases to eight.