Revision of the genus Phloeoditica Schedl - with description of two new genera and two new species in Phloeosinini (Coleoptera, Curculionidae, Scolytinae)

Abstract The genus Phloeoditica Schedl currently includes four species from Southeast Asia. These species vary substantially in important morphological characters and indicate the existence of multiple genera for these species. A revision based on morphological and in part molecular data resulted in the transfer of Phloeoditica setosa to Pseudoxylechinus the erection of a new genus Asiophilus for Phloeoditica phloeosinoides and a new species Asiophilus macropunctatus from Vietnam. Another new genus with affinities to Phloeoditica is described based on the new species Microditica uniseriata from Thailand. The new genera are included in a revised key to the tribe Phloeosinini.


Introduction
described the genus Phloeoditica based on the species Kissophagus curtus Eggers (1925). In the same publication he also transferred K. setosus Eggers (1939) to the same genus and described two new species, P. elegans and P. obscura. Browne (1966) added a fi fth species, P. phloeosinoides, which he with some hesitation placed in Phloeoditica. P. obscura Schedl was later transferred to Pseudodiamerus by Wood (1988). Th e doubts expressed by Browne and the uncritical inclusion of K. setosus and P. obscura in Phloeoditica by Schedl indicate a heterogeneous taxonomic history and a current uncertainty in the assembly of Phloeoditica species. Recent collections from Vietnam and Th ailand have furthermore revealed two additional undescribed species with affi liations to some of the species currently included in the genus. A revision is therefore needed.

Material and methods
Measurements follow the protocol by Wood (1982) and Jordal (1998). Four of the revised species were represented by only a single specimen in a condition which prevented genitalia and proventriculus preparations. Long series were available for the type species of Phloeoditica and one undescribed species in a closely related genus, which allowed dissections and DNA extraction. PCR amplifi cation followed primers and protocols given in Jordal and Hewitt (2004).

Type species: Kissophagus curtus Eggers
Diagnosis. Typical phloeosinine having a 5-segmented funicle and fl attened club with oblique sutures and broadly separated pro-and mesocoxae. Readily recognised by a unique pair of long denticles at the outer apical margin of protibiae, and an unusually long and laterally curved inner uncus.
Diagnosis: Interstriae broad and strongly elevated, with about three irregular rows of rounded scales and one median row of longer bristles separated on average by their length. Apex of metatibiae truncated and slightly excavated, surrounded by 4-5 proximally pointing small spines and a larger inner mucro. It is readily distinguished from P. elegans by the rounded scales on the interstriae. DNA sequences in Genbank: COI, GQ470889; EF1a, AF308402.
Description: Length 2.1-2.5 mm, 1.9-2.1 times longer than wide. Colour dark brown, with yellow setae. Head. Frons slightly convex, transversely impressed above epistoma, a weaker and more narrow impressed area in central area, sometimes with a narrow and shallow median longitudinal groove towards upper level of eyes. Frons fi nely pubescent, setae coarse and slightly longer in impressed area, a few longer setae along epistomal margin. Eyes three times longer (dorso-ventrally) than wide, separated above by 2.2 times their width. Antennal club large, one oblique suture indicated by weak septum and a second false suture indicated by setae. Funiculus 5-segmented, scapus about three quarter length of funiculus and club combined. Pronotum 0.85 times as long as wide, constricted on anterior fourth, anterior margin and notum smooth, shiny, punctures separated by half their diameter; short bristle-like setae from each puncture. Elytra 1.4-1.5 times longer than wide, 1.9-2.0 times longer than pronotum, sides parallel on anterior two-thirds, apex subacuminate due to elevated interstriae 1 and 3. Base of elytra moderately procurved and elevated by a complete row of crenulations. Striae deeply impressed, punctures large, subquadrate, separated by half the length of a puncture and formed by transverse ridges. Interstriae as wide as striae, strongly elevated, interstriae 2 and 4 less elevated on declivity, punctures obscure, small granules of variable size mainly on declivity. Interstriae 10 not elevated, reaches level of metacoxae. Vestiture consisting of 2-3 irregular interstrial rows of densely placed rounded scales and one central row of longer bristles, each separated on average by their length. Hind wing with weakly pigmented veins, stigmal patch without apical tubercles or setae, six short setae along costal margin of stigma, cluster of fi ve longer and softer costal setae at junction between R and SC-C. Sclerolepidia present along entire margin of metepisternum, small and hair-like; metepisternum with densely placed plumose scales. Legs. Procoxae separated by twothirds the width of one coxa. Precoxal ridges very short, sharp. Mesocoxae separated by the width of one procoxa, mesocoxal process slightly proclinate. Metacoxae broadly separated. Protibiae armed by a long inner uncus curved towards outer margin and three socketed teeth embedded in cuticle along the outer lateral margin, the lower two close together and of similar size (type) or the inner tooth shorter (Bangladesh series). Mesotibiae armed by 4 lateral, socketed teeth. Metatibiae armed by 2 small lateral socketed teeth close to apex and 4-5 additional small apical spines along the outer and inner apical margin forming a semi-closed corbel-like structure. Proventriculus with apical plate about one-third as long as proventriculus, without median suture, with about 7 transverse and blunt ridges; femoral teeth small, irregularly placed; closing teeth few, long and soft; mastigatory brush rather weakly developed. Aedeagus about 5 times longer than wide, narrowly rounded at apex; apophyses about 2.5 times longer than aedeagal body (not clearly demarcated); a pair of short and narrow terminal plates present at apex; long infl ated internal sac reaching half way between the apophyses, lightly sclerotised at apex. Tegmen a closed simple ring. Spiculum gastrale robust and L-shaped, with a tiny knob at posterior angle, about 0.8 as long as aedeagus. Female rectum with loop.
Comments. Th e type locality in Tenasserim is most likely in the province Tanintharyi of Myanmar (Burma). A designation of a lectotype is necessary because syntypes are mixed with specimens from diff erent localities. Th e series examined from Bangladesh diff er marginally from the type series collected in Myanmar and Vietnam by the smaller inner tooth at the protibial apex. Schedl, 1962 Figs 1b, 4b, 5b Phloeoditica elegans Schedl, 1962: 190 Type material examined. 2 paratypes: Vietnam with the following label data -"Tonkin, reg. de Hoa-Binh, A. de Cooman / Dauerpräparat nr 2081 Fuehler, coll. Schedl" and "Museum Paris, Tonkin, reg de Hoa-Binh, A. de Cooman 1929 / Dauerpräparat nr 2356 Fuehler, coll. Schedl" (NHMW).

Phloeoditica elegans
Diagnosis: Distinguished from P. curta by the smaller size and the less elevated interstriae having a single row of erect hair-like bristles on interstria 1 and irregular rows of hair-like bristles on the remaining interstriae. Th e fi rst suture of the antennal club has a more distinct septum visible without preparation.
Description: Length 1.7-2.0 mm, 2.0-2.2 times longer than wide. Colour dark brown, with yellow setae. Head. Frons convex, transversely impressed on lower half, especially just above epistoma. Short bristle-like setae evenly distributed from upper level of eyes to epistoma. Eyes three times longer (dorso-ventrally) than wide, separated above by 2.2 times their width. Antennal club large, one oblique suture indicated by a distinct septum and a second false suture indicated by setae only. Funiculus 5-segmented, scapus about three quarter length of funiculus and club combined. Pronotum 0.9 times as long as wide, weakly constricted on anterior third, anterior margin and notum smooth, shiny, punctures deep, subconfl uent; short spatula-shaped setae from each puncture. Elytra 1.5 times longer than wide, 1.9 times longer than pronotum, sides slightly diverging posteriorly, rounded behind. Base of elytra moderately procurved and elevated by a complete row of crenulations. Striae slightly impressed, punctures large, deep, transversely oval, separated by half the length of a puncture. Interstriae slightly wider than striae, slightly elevated, punctures at base of erect setae obscure. Interstriae 10 sharply elevated, reaches level of metacoxae. Vestiture consisting of 2-3 irregular interstrial rows of recumbent bristle-like setae slightly longer than distance between them and one central row of longer erect bristles each separated on average by 2-3 times their length. Sclerolepidia present along entire margin of metepisternum, small and hair-like; metepisternum with densely placed plumose scales. Legs. Procoxae separated by one-third the width of one coxa. Precoxal ridges very short, sharp. Mesocoxae separated by the width of one procoxa, mesocoxal process proclinate. Protibiae armed by a long inner uncus curved laterally and three socketed teeth embedded in cuticle along the outer lateral margin, the lower two of similar size and closer together, much larger. Mesotibiae armed by 4 lateral, socketed teeth. Metatibiae armed by 3 lateral socketed teeth close to apex.
Comments. Types were mounted on cardboard which prevented examination of posterior ventral body parts. Types were not dissected for internal characters. (Eggers, 1939), comb. n.
Diagnosis. Distinguished from all genera in Phloeosinini by the strongly concave frons and further from Phloeoditica and Microditica genus nov. by the visible large and dome shaped scutellum, and by the gradually rounded lateral margin of the protibia having socketed teeth. It is distinguished from other Pseudoxylechinus species except P. indicus Wood by the strongly concave frons and hair-like ground vestiture, and further from P. indicus by the more obtusely rounded lower lateral margin of the impressed frons, by the broader pronotum, and by the broader interstriae.
Description: Length 2.7 mm, 2.1 times longer than wide. Colour dark brown with yellow setae. Head. Frons deeply concave between eyes from epistoma to upper level of eyes, upper half of impressed area reticulate with minute granules, shin-ing below. Vestiture consisting of moderately long coarse setae over impressed area, slightly longer setae along lateral margin, sparse, minute setae above eyes. Eyes three times longer (dorso-ventrally) than wide, separated above by 3 times their width. Antennal club fl attened, with one septate suture; funiculus possibly 6-segmented. Pronotum 0.8 times as long as wide, constricted on anterior third, anterior margin and notum lightly rugose, reticulate, punctures shallow, confl uent; vestiture consisting of dense hair-like setae interspersed by a smaller number of longer and coarser bristles. Elytra 1.5 times longer than wide, 2.1 times longer than pronotum, sides subparallel on anterior two-thirds, rounded behind. Base of elytra procurved and elevated by a complete row of crenulations. Striae weakly impressed, punctures small, shallow, separated on average by less than their diameter. Interstriae three times wider than striae, weakly elevated, feebly granulated, punctures obscure. Interstria 10 not elevated, short, reaching beginning of metepisternum. Vestiture consisting of 4-5 irregular interstrial rows of hair-like setae (ground vestiture) and one central row of longer bristles each separated on average by their length. Sclerolepidia present along entire margin of metepisternum as small plumose scales; metepisternum with densely placed plumose scales. Legs. Procoxae separated by about half the width of one coxa (covered in glue). Precoxal ridges very short, sharp. Protibiae armed by six socketed teeth along the lateral and apical margin, the uppermost teeth half way and the remaining fi ve close to the apical margin, inner uncus distinctly curved caudally. Mesotibiae armed by 4 lateral, socketed teeth. Metatibiae armed by 3 small lateral socketed teeth close to apex.
Comments. Th e holotype has lost both antennae and only a badly preserved microscope slide of the non-type specimen was available, indicating most likely a 6-segmented funicle. However, the similarity in other characters to the species of Pseudoxylechinus Wood and Huang (1986) is striking and the species undoubtedly belongs here. Some authors have noted that Pseudoxylechinus may be a synonym of the recently resurrected genus Longulus Krivolutskaya, but the two genera remained separate in the absence of suffi cient type material (Mandelshtam et al., 2007). Most species of Pseudoxylechinus are nevertheless distinguished from Longulus by having a distinctly impressed lower male frons, particularly so in P. indicus and P. setosus (see Wood 1986).
Th e distribution of the genus ranges from Japan in the east, via Yunnan and Tibet to Darjeeling in the west (Wood 1986 Diagnosis: A typical phloeosinine genus with 5-segmented funicle, fl attened club with two oblique sutures and widely separated pro-and mesocoxae. It is readily distin-guished from Phloeosinus by the entire eye and less produced outer apical margin of the protibiae, and by the ascending venter.
Description: Body length 1.5-1.65 mm. Frons convex; eyes entire, distance between eyes 2.7-2.9 their width; funicle 5-segmented, antennal club large and moderately fl attened, with two oblique sutures. Pronotum and elytra roughly punctured, with a pair of medial closely set erect setae. Scutellum large, fl at, slightly sunken with a small depression in elytra around scutellum; elytral base procurved, raised with a single complete row of crenulations. Metepisternal setae hair-like or bifi d. All coxae widely separated; protibiae with 5-6 lateral and apical socketed teeth. Venter ascending to meet elytral apex.
Etymology. From the Greek word philos (having affi nity for) and Asia, referring to the type localities in Vietnam and Philippines.
Comments. Browne (1966) placed Phloeoditica phloeosinoides in Phloeoditica with much hesitation and referred to several characters that deviate from P. curta and P. elegans, e.g. the larger and dorsally visible scutellum, the scant vestiture, and two real sutures in the antennal club. Species of this genus bear some superfi cial resemblance to the hylesinine genus Ficicis, but is readily distinguished by the 5-segmented funicle and the lack of pronotal asperities. Taxa included: A. phloeosinoides (Browne) and A. macropunctatus Jordal, sp. n.
Diagnosis. Distinguished from A. macropunctatus by the more sparsely punctured frons, by the less asperate interstriae, by the scant elytral vestiture, and by the protibiae bearing 5 and not 6 lateral socketed teeth.
Description: Length 1.5 mm, 2.0 times longer than wide. Colour dark reddishbrown. Head. Frons weakly convex above to fl attened below, transversely impressed just above epistoma; punctures few, small and shallow. Vestiture consisting of 5-6 setae along epistomal margin, and almost invisible fi ne setae above. Eyes three times longer (dorso-ventrally) than wide, separated above by 2.7 times their width. Antennal club large, moderately fl attened and oval, with two regularly spaced oblique sutures, fi nely pubescent. Funiculus 5-segmented, scapus about 0.8 times as long as the length of funiculus and club combined. Pronotum 0.85 times as long as wide, distinctly constricted on anterior third, notum roughly punctured, weakly granulated along anterior-lateral areas, punctures irregularly separated by about half their diameter; vestiture consisting of scant minute setae in punctures and a pair of medially placed longer erect setae. Elytra 1.3 times longer than wide, 1.7 times longer than pronotum, sides subparallel on anterior half, apex rounded. Base of elytra procurved and elevated by a complete row of crenulations. Striae impressed, punctures variably large, deep, subconfl uent. Interstriae as wide as striae, slightly elevated, rugose, shining, with punctures about half the size of strial punctures and more widely spaced. Interstriae 10 reaching level of metacoxae. Vestiture consisting of interstrial rows of tiny recumbent setae. Sclerolepidia present along entire margin of metepisternum, very small; metepisternum almost glabrous, with scant minute setae. Legs. Procoxae separated by width of one coxa. Precoxal ridges short, distinct. Mesocoxae separated by slightly more than the width of procoxa, mesocoxal process vertical. Protibiae armed by 5 socketed teeth along the lateral and apical margin and one lightly curved inner mucro. Mesotibiae armed by 5 lateral, socketed teeth. Metatibiae armed by 4 lateral socketed teeth on apical half.

Asiophilus macropunctatus
Diagnosis. Distinguished from A. phloeosinoides by the more coarsely punctured frons and pronotum, by the elytral vestiture consisting of bristle-like interstrial setae, and by the protibiae bearing 6 lateral socketed teeth.
Description: Length 1.65 mm, 2.0 times longer than wide. Colour dark brown or black. Head. Frons weakly convex, transversely impressed just above epistoma, punctures large, nearly confl uent. Scant minute setae in punctures, about 12 longer setae along the epistomal margin. Eyes three times longer (dorso-ventrally) than wide, separated above by 2.9 times their width. Antennal club large, moderately fl attened and oval, with two regularly spaced oblique sutures, fi nely pubescent. Funiculus 5-segmented, scapus about 0.8 times as long as the length of funiculus and club combined. Pronotum 0.8 times as long as wide, distinctly constricted on anterior third, notum roughly and densely punctured, punctures subconfl uent; vestiture consisting of scant minute setae in punctures and a pair of median longer erect setae. Elytra 1.3 times longer than wide, 1.9 times longer than pronotum, sides subparallel on anterior two-thirds, apex rounded. Base of elytra strongly procurved and elevated by a complete row of crenulations. Striae impressed, punctures large, deep, separated by about one-quarter their diameter. Interstriae as wide as striae, slightly elevated, rugose, shining, with irregularly sized and more widely spaced punctures about half the size of strial punctures. Interstriae 8 and 9 on posterior half more elevated and sharply crenulated; interstriae 10 reaching level of metacoxae. Vestiture on disk consisting of interstrial rows of recumbent hair-like setae separated by less than their length, strial setae minute; on declivity interstrial setae in two confused rows. Sclerolepidia present along entire margin of metepisternum, very small; metepisternum with scant bifi d setae, densely clothed closer to endosternum. Legs. Procoxae separated by width of one coxa. Precoxal ridges short, distinct. Mesocoxae separated by slightly more than the width of procoxa, mesocoxal process vertical. Protibiae armed by 6 socketed teeth along the lateral and apical margin and one lightly curved inner mucro. Mesotibiae armed by 6 lateral, socketed teeth. Metatibiae armed by 5 lateral socketed teeth on apical half.
Comments. Only known by the unique type specimen from high altitude in Northern Vietnam. Diagnosis. Typical phloeosinine genus with a 5-segmented funicle, barely visible scutellum and the broadly separated pro-and mesocoxae. Th e genus is diagnosed by the unique long and laterally curved inner uncus (mucro) of the protibiae, by the deeply grooved antennal club, and by the short crenulations at the elytral base reaching only to interstriae 5.
Description: Frons convex and nearly glabrous in both sexes; eyes entire; funicle 5-segmented, antennal club large, with deeply grooved sutures. Pronotum smooth and shiny. Scutellum very small, fl ush with elytra and mainly visible on anterior slope. Elytral base nearly straight, with a single row of crenulations from scutellum to interstriae 5. Metepisternal setae scale-like; sclerolepidia distinct, small. Protibiae with the inner uncus very large and curved laterally, lateral teeth apparently unsocketed. Hind wings with four setae along costal margin at stigmal patch, hind margin from base to tip with long setae. All coxae widely separated, mesosternal process vertical. Postnotum fused to metanotum, scutoscutellar suture parallel to sutural groove for two-third of its length, then curves relatively abruptly laterally. Proventriculus simple, without apical sutural teeth or posterior mastigatory brush. Male aedeagus weakly sclerotised, spiculum gastrale weakly forked and tegmen a simple ring.
Etymology. Th e Greek name micro (small) refers to the small size of a bark boring beetle; ditica is a Latinised form of the Greek feminine adjective dytiké (that likes to penetrate) (Alonso-Zarazaga and Lyal 2009).
Comments: Th is genus shares most characteristics with Phloeoditica but is readily distinguished by the diff erently shaped protibia, the incomplete row of crenulations at the base of elytra, by the lack of ground vestiture, by the number and position of setae on the front and hind margin of the hind wings, and by the scutoscutellar suture following the scutellar grove much longer posteriad. Th e long setae along the hind margin are typical for small sized beetles (Kuschel 2000) and may not be of signifi cant   phylogenetic value. Phylogenetic analyses of combined COI and EF-1α nucleotide data show that Microditica and Phloeoditica are quite unrelated and do not necessarily form a monophyletic group (unpublished data). Th is taxon share a few characters with other tribes such as Phloeotribini (semiarticulated antennal club) and Hypoborini (interrupted row of crenulations at base of elytra), but is readily distinguished from all taxa in those tribes by the broadly separated coxae.   840E, 21 Nov. 1999 K. Harkestad, leg. (NHCB). Paratypes: Same locality as holotype (8 specimens, NHCB).

Microditica uniseriata
Diagnosis. Very small body size; frons convex and shining in both sexes; large club with two deep grooves; protibiae with large inner uncus directed laterad; base of elytra with a single row of crenulations between scutellum and interstriae 5; uniseriate rows of interstrial spatulate bristles. DNA sequences in Genbank: COI, GQ470890; EF1a, GQ470891) Description. Length 0.85-0.95 mm, 2.0-2.1 times longer than wide. Colour light brown. Head. Frons convex, shiny, sparsely dotted by small shallow punctures separated by 2-4 times their diameter. Vestiture consisting of sparse minute hair-like setae, a few longer setae close to epistoma. Eyes 2.5 times longer (dorso-ventrally) than wide, separated above by 2.4 times their width. Antennal club large, two segments clearly marked by deep grooves, almost articulated; funiculus 5-segmented; scapus about 0.7 times as long as funiculus and club combined. Pronotum 0.95 times as long as wide, broadly rounded anteriorly, constriction on anterior fourth vaguely indicated. Disk smooth, shiny, with small and shallow punctures variably separated by 1-3 times their diameter. Vestiture consisting of scant minute hair-like setae and two median pairs and two anterior pairs of longer setae. Elytra 1.2 times longer than wide, 1.6 times longer than pronotum. Sides subparallel on anterior half, apex rounded. Base of elytra straight, with a single row of raised crenulations between scutellum and interstriae 5. Striae lightly impressed, punctures large, deep, separated by half their diameter. Interstriae smooth, punctures obscure, with a single row of small granules mainly on declivity and associated with the base of setae. Interstriae 10 not elevated, reaching level of metacoxae. Vestiture consisting of interstrial rows of erect spatulate bristles, each separated on average by their length. Sclerolepidia present along entire metepisternal suture, sparse metepisternal scale-like setae. Legs. Procoxae separated by width of 1 coxa; precoxal ridges very short but distinct. Mesocoxae 1.2 times wider than one procoxa; mesocoxal process vertical. Metacoxae broadly separated. Protibiae with two lateral unsocketed teeth, a third tooth just mesal to the second tooth, then gently curved to meet a large and laterally curved inner uncus. Mesotibiae and metatibiae each armed by 4 lateral socketed teeth. Proventriculus simple, apical plate short, about one-quarter of total length, with 3-4 transverse blunt ridges or rugae; femoral teeth weakly developed at base of 4-5 closing teeth. Mastigatory brushes not developed. Aedeagus weakly sclerotised, about 6-7 times longer than wide, apophyses very thin, longer than aedeagal body; tegmen a simple ring. Spiculum gastrale slightly shorter than aedeagus, weakly forked in the caudal end.
Etymology. Th e specifi c epithet uniseriata refers to the uniseriate rows of interstrial bristles.
Comments. M. uniseriata has been collected only from the type locality and was taken from the bark of an unknown dead shrub together with Hypothenemus birmanus (Eichhoff ).