Ithyphenes australiaensis Kirejtshuk, 2022

Kirejtshuk, Alexander G. & Kovalev, Alexey V., 2022, Monograph on the Cillaeinae (Coleoptera: Nitidulidae) from the Australian Region with comments on the taxonomy of the subfamily, Zootaxa 5103 (1), pp. 1-133 : 93-97

37. Ithyphenes australiaensis Kirejtshuk et Kovalev, sp. nov.

Figs 28 , A–I

LSID urn:lsid:zoobank.org:act:EF694239-FD8F-41E3-A63A-1992B09C292E

Type specimens examined. Australia, NSW: Holotype, male ( ANIC)—“ 3 km N of Landsowne, NSW, Emgd , 15– 29 May, 1983, C/& N/ Williams ”, “dead ficus oblique branch”; QLD: 1 paratype, female ( ZIN)—“ 16.04S 145.28E, QLD, CT1 10 m, 1km WNW, Cape Tribulation, 31 May—28 June 1996, P. Zborowski, FI Trap JCU.”

Diagnosis. This new species can be diagnosed from the Australian congeners due to the above key to Australian species of the genus. In addition to the above key, Ithyphenes australiaensis sp. nov. and I. rectifrons sp. nov. are different also in the antennomeres 2 and 3 and width of femora (see their descriptions). These two Australian species by some particular characters are somewhat similar to different Indo-Malayan species which were proposed in composition of “ Platynema ”, but the new species distinct from them in many other structural features. In the contrast to other formerly regarded as members of “ Platynema ”, this new species has the comparatively more subparallel-sided body, slightly modified anterior part of frons, shorter head, longer prothorax, and also the absence of long and thin hairs along thorax and abdomen. The anterior edge of frons and many other features of it are rather similar to those in Ithyphenes breviceps comb. nov., but the new species is distinct from the latter in the longer and narrower prothorax, more expressed striae with punctures on elytra, longer abdominal segments, wider pregenal processes, strongly projecting anterior angles of mentum, markedly shorter and wider oviform ultimate labial palpomere (not subcylindrical as in I. breviceps comb. nov.), antennal grooves extending behind eyes, subtruncate apex of prosternal process (not widely arcuate as in I. breviceps comb. nov.), male pygidium about 1.5 × as long as wide (in I. breviceps comb. nov. the male pygidium slightly longer than wide), weaker serration along the posterior edge of male anal sclerite. Another congener with similar anterior edge of slightly modified frons compared with Ithyphenes australiaensis sp. nov. is I. planiceps comb. nov., but the new species differs from the latter in the markedly weakly projecting lateral angles of frons, and also in the more convex and more subparallel-sided body, scape longer and less swollen anteriorly (in I. planiceps comb. nov. the scape less than 2.0 × as long as thick), more consolidated antennal club (in I. planiceps comb. nov. antennomeres 9 and 10 more separated) markedly shorter head, prothorax much longer and subrectiliner at sides (not rounded as in I. planiceps comb. nov.), absence of very long and fine conspicuous hairs along sides of abdominal segments, markedly weaker mandibles.

It can be compared also with the species formerly included into “ Platynema ”, particularly, with the following species:

– with Ithyphenes angustus comb. nov. possessing many characters similar to those in I. australiaensis sp. nov.; however. this new species differs from the latter in the more convex, more subparallel-sided and somewhat lighter body; shorter and thicker antennomeres 2 and 3 (in I. angustus comb. nov. antennomeres 2 and 3 almost 2.0 × as long as thick); more compact antennal club (antennomeres 9 and 10 only slightly separated); weaker mandibles; slightly projecting three processes of frons (frons of I. angustus comb. nov. has only a pair of strongly projecting lateral processes (anterior angles) and deep arcuate excision between them); markedly shorter head, prothorax much longer and subrectiliner at sides (not rounded as in I. angustus comb. nov.); absence of very long and fine conspicuous hairs along sides of metaventrite and abdominal segments; wider pregenal processes; strongly projecting anterior angles of mentum; much wider antennal grooves extending behind eyes; shape of sclerites of ultimate abdominal segment in both sexes; finer serration of posterior edge of male anal sclerite;

– with I. fuscipennis comb. nov.) demonstrating a considerable similarity to I. australiaensis sp. nov.; but the new species differs from the latter in the more convex, more subparallel-sided and somewhat lighter subunicolorous body; slightly projecting three processes of frons (frons of I. fuscipennis comb. nov. has only a pair of strongly projecting lateral processes (anterior angles) and deep arcuate excision between them); shorter antennomeres 2 and 3 (in I. fuscipennis comb. nov. at least antennomere 2 more than 2.0 × as long as thick); markedly shorter head; prothorax much longer and subrectiliner at sides (not rounded as in I. fuscipennis comb. nov.); absence of very long and fine conspicuous hairs along sides of thorax and abdominal segments; markedly weaker mandibles; wider pregenal processes; strongly projecting anterior angles of mentum; much wider antennal grooves; shape of sclerites of ultimate abdominal segment in both sexes (particularly, due to wider base and arcuate (not suparallesided) sides); finer serration of posterior edge of male anal sclerite;

– with I. japonicus comb. nov. demonstrating a considerable similarity to I. australiaensis sp. nov.; but the new species differs from the latter in the more convex, more subparallel-sided and somewhat darker subunicolorous body; slightly projecting three processes of frons (frons of I. japonicus comb. nov. has only a pair of strongly projecting lateral processes (anterior angles) and deep arcuate excision between them); markedly shorter head; prothorax much longer and subrectiliner at sides (not rounded as in I. fuscipennis comb. nov.); absence of very long and fine conspicuous hairs along sides of abdominal segments; somewhat weaker mandibles; shape of sclerites of ultimate abdominal segment in both sexes; finer serration of the posterior edge of male anal sclerite;

– with I. ritsemai comb. nov. demostrating also some similarity to I. australiaensis sp. nov.; but the new species differs from the latter in the more convex, more subparallel-sided and somewhat lighter subunicolorous body; slightly projecting three processes of frons (frons of I. fuscipennis comb. nov. has only a pair of strongly projecting lateral processes (anterior angles) and deep arcuate excision between them); shorter antennomeres 2 and 3 (in I. fuscipennis comb. nov. at least antennomere 2 more than 2.0 × as long as thick); markedly shorter head; prothorax much longer and subrectiliner at sides (not rounded as in I. fuscipennis comb. nov.); absence of very long and fine conspicuous hairs along sides of thorax and abdominal segments; markedly weaker mandibles; wider pregenal processes; strongly projecting anterior angles of mentum; much wider antennal grooves; shape of sclerites of ultimate abdominal segment in both sexes (particularly, due to the wider base and arcuate (not suparallesided) sides); finer serration of the posterior edge of male anal sclerite;

– with I. saundersi comb. nov. demostrating some similarity to I. australiaensis sp. nov.; but the new species differs from the latter in the more convex, more subparallel-sided and somewhat lighter subunicolorous body; slightly projecting three processes of frons (frons of I. fuscipennis comb. nov. has only a pair of strongly projecting lateral processes (anterior angles) and deep arcuate excision between them); shorter antennomeres 2 and 3 (in I. fuscipennis comb. nov. at least antennomere 2 more than 2.0 × as long as thick); markedly shorter head; prothorax much longer and subrectiliner at sides (not rounded as in I. fuscipennis comb. nov.); absence of very long and fine conspicuous hairs along sides of thorax and abdominal segments; markedly weaker mandibles; wider pregenal processes; strongly projecting anterior angles of mentum; much wider antennal grooves; shape of sclerites of ultimate abdominal segment in both sexes (particularly, due to wider base and arcuate (not suparallesided) sides); finer serration of the posterior edge of male anal sclerite.

Etymology. The epithet new species is formed from the Australia.

Description of holotype (male). Length of body with abdomen 6.8, length without abdomen 4.0, width 1.2, height 0.7 mm. Elongate, subflattened dorsally and rather convex ventrally; subunicolorous reddish with somewhat darkened elytra; moderately shining; almost without pubescence, although posterior edge of pronotum with dense microsetae, abdominal sclerites with short and thin inconspicuous yellowish setae, posterior edge of anal sclerite with thin and long hairs.

Head and pronotum with punctures, slightly coarser than eye facets, separated by 3.0–4.0 × greater than one puncture diameter, interspaces between them smooth to slightly alutaceous; elytra with weak and slightly oblique striae coordinated with shallow punctures in bottom of these striae (punctures about as coarse as those on head and pronotum); exposed abdominal dorsal sclerites with shallower and somewhat finer punctures than those on head and pronotum, and obliterately microreticulate interspaces between them. Prosternum and metaventrite with rather fine and sparse punctures along middle, interspaces between punctures smooth.

Head widest behind eyes and slightly arcuately narrowing posteriorly, temples about 1.5 × as long as eye.Anterior part of frons subflattened, its anterior edge with slight median projection and one couple of slight paramedian lateral projections. Labrum slightly exposed from under frons and visible from above, with widely rounded and sparsely serrate anterior edge of lobes. Mandibles moderately stout and with bidentate apex strongly curved downwards, subtransverse anterior edge and gently rounded at side.Antennae slightly longer than head wide; scape comparatively narrow and slightly curved, about 2.0 × as long as each of antennomeres 2 and 3; antennomere 2 (pedicel) slightly thicker than antennomere 3; oblong club about 0.3× total antennal length, somewhat more than 2.0 × as long as wide, with antennomeres 9 and 10 comparable in width and length and somewhat separated from each other, and slightly wider and longer than antennomere 11, apex of terminal antennomere rounded to subacute. Pronotum about 1.3 × as long as wide and somewhat rectilinearly widening posteriorly, anterior edge almost straight and posterior one evenly convex, posterior angles widely rounded. Scutellar shield subtriangular, about 2.0 × as wide as long. Elytra slightly widening posteriorly, nearly 1.5 × as long as their combined width, moderately steeply sloping at narrowly explanate sides. Abdomen about as wide as pronotum with only distal part of segment 4 exposed dorsally and with laterosternites clearly widened posteriorly, segment 5 almost 2.0 × as wide as long, tergite VI somewhat longer than tergite V; postbasal lines of exposed tergites behind elytral apices well expressed and their lateral ends reaching middle of tergites. Pygidium nearly 1.2 × as long as wide, widely rounded at apex.

Pregenal processes comparatively narrow and at wide hypostomal sinuses subarcuately curved. Terminal maxillary palpomere more than 2.5 × as long as thick and subcylindrical. Terminal labial palpomere slightly longer than thick, subovoid and with oblique apex. Mentum rather widened anteriorly and with sides of mentum about 2.0 × as long as its median part. S-shaped antennal grooves somewhat divergent, their inner side quite distinct behind posterior level of eye. Median plate of prosternum almost flatly widened anteriorly from prosternal process. Prosternal process strongly widened before subtruncate apex, its apex nearly 2.0 × as wide as distance between procoxae. Distance between procoxae about 0.5 × as great as length of antennal club, and somewhat smaller than that between mesocoxae and somewhat greater than that between metacoxae. Mesothoracic median plate distinctly isolated by longer lateral ridges. Metaventrite subflattened and with clear discrimen in distal third. Metepisterna gradually narrowing posteriorly and at base about as wide as mesotarsomere 1. Abdominal ventrite 1 somewhat longer than ventrite 2 and somewhat shorter than each of ventrites 3 and 4. Hypopygidium somewhat transverse and with shallowly emarginate posterior edge.

Pro- and mesofemora about 3.0 × as wide as corresponding tibiae and metafemora almost 3.5 × as wide as corresponding tibia. Protibia somewhat narrower than antennal club, comparatively coarsely serrate along outer edge. Meso- and metatibiae somewhat narrower than protibia, with two unclear rows of short and stout spines along outer edge. Protibia with very long and stout spur, meso-and metatibiae with moderately long spurs. Tarsi with thickest tarsomere 1 (slightly wider than antennomere 2), following tarsomeres thinner, claws simple and narrow.

Anal sclerite with subtruncate and serrate apex bearing ten teeth (including one very small tooth at each side). Aedeagus moderately sclerotized and comparatively small, tegmen widely rounded at apex; penis trunk about as long as tegmen, somewhat arcuate at sides and nearly widely rounded at apex.

Female. Length of body with abdomen 5.6 mm. Differs from male in structure of terminal abdominal segment: more coarsely and widely rounded apex of pygidium (about 1.3 × as long as wide) bearing ten small teeth and widely rounded apex hypopygidium. Mandibles with arcuate anterior edge and roundly angular at side, their apex slightly turning downwards. Ovipositor moderately sclerotized and rather wide; gonocoxites comprising almost 0.4 of entire length, lateral lobes slightly sclerotized and about 0.5 × as long as gonocoxites in general, outer outline of gonocoxites slightly concave and sinuated posteriorly from apices of lateral lobes, moderately narrow apex with moderately long styli located at great distance from apex.

Distribution. This species is known only from type locality in NSW (Landsowne) and QLD (Cape Tribulation).

Notes on bionomy. This species can be associated with dying and dead trees (dead Ficus obliqua branch”).

Figures

FIGURE 28. Ithyphenes australiensis sp. nov., orig. A–D, F–H: holotype, male from NSW (“3 km N of Landsowne …”); E, I: paratype from QLD (“… Cape Tribulation…”); A: body, dorsal; B: head, dorsal; C: head, ventral; D: thorax, ventral; E: terminal abdominal segment, ventral; F: male anal sclerite, ventral; G: tegmen, ventral; H: penis trunk, dorsal; I: ovipositor, ventral. Scale bars: a = 1.0 mm to Fig. A; b = 0.5 mm to Figs B–E; с = 0.25 mm to Figs F–I.