Macratria tigrina, Telnov, 2023

Telnov, Dmitry, 2023, Fourth contribution to the Macratriinae LeConte, 1862 of the Papuan Region and Wallacea (Coleoptera: Anthicidae) with descriptions of sixteen new species, Zootaxa 5361 (1), pp. 1-52 : 46-48

Macratria tigrina sp. nov.

urn:lsid:zoobank.org:act:E4328385-69A1-4C1E-9164-A83A9A0A2859

( Figs 125–137 )

Type material designated. Holotype ♂ NME: INDONESIA E, New Guinea, Papua Prov., Sentani 40 km W, road to Demta vill., Berab vill., 02°30’06’’S 140°08’’2’’E, 33 m, 02.IV.1998, sago swamp, from Metroxylon sp. [printed].

Paratypes 4 specimens. 1♂, 1♀ NME & 1♂, 1♀ DTC: same label as holotype.

Derivatio nominis. Named after the tiger ( Panthera tigris ) for the yellow-black striped antennomeres 7–10 of the new species.

Measurements, holotype male, total body length 4.6 mm; head length 1 mm, head width across compound eyes 0.7 mm, pronotal length 1.1 mm, maximum pronotal width 0.7 mm, elytral length 2.5 mm, combined maximum elytral width 1.05 mm. Male paratypes 4.5–4.6 mm, female paratypes 4.2–4.5 mm long.

Description. Male ( Figs 125–137 ). Dorsum and venter nearly uniformly black. Mouthparts including maxillary palpi yellow and antennomeres 1–7 yellow. Antennomeres 7–10 transversely black-brown medially, yellowish rufous at anterior and distal tips. Pro- and mesothoracic legs yellow, tibia shortly brown at contact point with femur, coxa and trochanter brown. Metathoracic leg brown, two ultimate metatarsomeres yellow. Head moderately glossy dorsally and ventrally, elliptical, distinctly narrows towards base. Frons narrow, about 0.4× as wide as dorsal eye length. Compound eye large, occupying most of lateral side of head beyond antennal insertion, moderately protruding from lateral outline of head. Interfacetal setae long, dense. Tempus long, strongly constricted towards head base. Head base narrowly rounded. Frontoclypeal suture or impression not observed. Head dorsal punctures variably large but generally small and rather shallow, distinctly denser on anterior part of frons and lateral sides of vertex compared to median area of frons and vertex. Intervening spaces smooth, narrower than to 4× as wide as punctures. Head dorsal setae white, subdecumbent, dense, directed in part transversely, in part longitudinally. Tactile setae sparse, erect, not or slightly longer but thinner compared to ordinary setae. Antenna slender and strongly filiform, extending towards mesocoxal cavity when directed posteriad. Basal antennomere elongate, about 2.3× as long as antennomere two. Antennomere three about 1.6× as long as antennomere two, about 0.8× as long as antennomere four. Antennomeres 3–11 long and slender, antennomere eight widened fusiform, 9–10 widened distally. Terminal antennomere long and slender, acutely pointed, about twice to 2.2–2.3× as long as penultimate antennomere. Terminal maxillary palpomere subcultriform. Pronotum moderately glossy dorsally and on prothoracic hypomeron, slightly convex in dorsal aspect, elongate cylindrical, as wide as head across compound eyes. Anterior margin narrow, subtruncate. Lateral margins constricted laterally anteriad and less prominent so towards base. Dorsal pronotal punctures larger and denser than those on head, moderately deep. Intervening spaces transversely microstrigose, generally narrower than to as wide as punctures. Pronotal dorsal setation double, not fully concealing dorsal sculpture of pronotum. Whitish setae are thicker, denser and appressed, yellowish setae are thinner, subdecumbent, sparser. Tactile setae sparse, erect, not longer than ordinary yellowish setae. Scutellar shield small, truncate at posterior margin. Elytron elongate, moderately glossy, gradually narrows posteriad. Humerus broadly rounded. Postbasal transverse impression not indicated. Punctures on each elytron in anterior half arranged into six incomplete, flat, irregularly shaped rows; punctures subconfluent in corresponding rows. Intervening spaces between rows minutely punctate and microstrigose. Elytral setation yellowish, moderately dense, long, directed posteriad, subdecumbent, not concealing dorsal sculpture of elytron. Those setae adjacent to suture directed slightly obliquely laterally. Slightly transverse patch of denser, stronger appressed, somewhat thicker setae in basal and somewhat longitudinal patch in apical third, both not touching suture and intermixed with ordinary yellow setae. Tactile setae sparse, erect, not longer than ordinary setae. Lateral humeral stria not visible in dorsal view. Sutural stria complete, rather broad. Metathoracic wing fully developed. Legs long. Male metatibia in distal half with series of several long, straight to slightly sinuous whitish setae ( Fig. 127 ). Tibial terminal spurs paired, serrate. Basal metatarsomere distinctly longer than combined length of remaining tarsomeres. All claws strongly dentate at base. Metaventrite deeply, narrowly longitudinally impressed at place of metathoracic discrimen. Male tergite VII elongate, strongly narrowing posteriad, narrowly rounded at posterior margin, with about ten long setae along lateral and posterior margins ( Fig. 128 ). Male morphological sternite VII ( Figs 129–132 ) short and broad, with paired, long, sinuous-angulate at inner margin, preapically at external margin somewhat notched, apically rounded prong; prong apically rounded and here densely setose, inner margin at place of angulation with a row of short, thickened setae; posterior margin of sternite VII medially deeply U-shapedly emarginate, lateral margins strongly produced posteriad, narrow and acutely angulate. Tergite VIII, morphological sternites VIII and IX as in Fig. 133 . Aedeagus ( Figs 134–135 ) moderately broad, basale nearly 3× as long as short apicale, paramere short, apically rounded. Median lobe apically tripartite.

Sexual dimorphism. Female pro- and mesothoracic legs brown, only distal part of tibia and tarsus paler yellow, terminal antennomere about 2.2–2.3× as long as penultimate antennomere, and elytra comparatively shorter. Female tergite VII narrowing posteriad, rounded at posterior margin ( Fig. 136 ), morphological sternite VII broadly subtriangular, shortly rounded medially at posterior margin ( Fig. 137 ).

Differential diagnosis. Macratria tigrina sp. nov. belongs to the gestroi species-group and is unique among all congeners primarily in the peculiar shape of the male antennomere eight (widened fusiform), the colouration of the antennomeres 7–10, the head strongly constricted posterior to compound eyes and the unique shape of the terminalia and aedeagus. Also see diagnose of M. sentani spp. nov. above.

Ecology. Collected from leaves of sago palm ( Metroxylon sagu ) in a swampy area at edge of primary lower montane rainforest.

Distribution. Northern lowlands, New Guinea.

Figures

FIGURES 125–127. Macratria tigrina sp. nov., holotype ♁. 125—Habitus, dorsal view; 126—Forebody, dorsal view; 127— Right metatibia, dorsal view [not to scale].

FIGURES 128–137. Macratria tigrina sp. nov. 128—Paratype ♁, tergite VII, dorsal view; 129—Same, morphological sternite VII, ventral view; 130—Same, morphological sternite VII, median part of lateral prong; 131—Morphological sternite VII, apices of lateral prongs, ventral view; 132—Morphological sternite VII, median part of posterior margin, ventral view; 133—Same, morphological tergite VIII, morphological sternites VIII and IX, ventral view; 134—Same, aedeagus; 135— Same, aedeagus, apical portion; 136—Paratype ♀, tergite VII, dorsal view; 137—Same, morphological sternite VII, ventral view [not to scale].