Triplax ainonia Lewis, 1887

Park, Boo Hee Jung and Haechul, 2017, First record of two erotylid species of Triplax (Coleoptera: Erotylidae: Tritomini) from Korea, Journal of Species Research 6 (3), pp. 291-294 : 292-293

Triplax ainonia Lewis, 1887

[Korean name: Neu-ta-li-beo-seos-beol-re] [ Figs. 1 , 3 , 5 ] Triplax ainonia Lewis, 1887: 69 .

Re-description: Body length 3.0- 3.5 mm. Body elongate oval, weakly convex, color mostly black and shiny; strongly glabrous; 1-8 antennomeres (9-11 antennomeres blackish brown), mouthpart, pronotum and legs yellowish brown to reddish brown; pronotum with two transverse and black spot, one placed at middle of basal margin and the other placed at middle of anterior margin; ventral part mostly black, but yellowish brown at lateral and apical part. Head finely punctate; shallowly depressed at each side; vertex with black circular marking; ocular distance about 2.2 times wider than eye diameter; antenna reaching to middle of pronotum; third antennomere about 1.8 times longer than fourth; 9-11 antennomeres forming a loose club; ninth antennomere triangular, tenth antennomere bowl-shaped and apical antennomere rotundate; apical maxillary palpomere about 2.5 times wider than long. Pronotum weakly convex, about twice

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wider than long; finely and a little sparsely punctate; with a pair of bilateral- symmetrical, circular and black markings; anterior margin weakly round, thinly rimmed; lateral sides subparallel-sided, gradually narrow anteriorly, with a small pore at each; basal margin strongly arched posteriorly at median part, distinctly rimmed. Scutellum almost cordiform, with fine punctures. Elytra weakly convex; striate-punctate; strial punctures distinct; interstriae weakly flat, with small and somewhat sparse punctures. All tibiae of legs strongly widened apically; 1-4 tarsomeres with dense setae ventrally; fourth tarsomere minute, inserted into third; fifth tarsomere almost equal to four preceding tarsomeres combined together. Male gentalia with median lobe and median stout as in Fig. 3 .

Specimens examined: [GG] 1 ex. Deoksu-ri, Danweol-myeon, Yangpyeong-gun, 21.vi-30.vi.2016, J.B. Seung and B.H. Jung (FIT); 1 ex. Deoksu-ri, Danweol-myeon, Yangpyeong-gun, 2.vi.-17.vi.2016, J.B. Seung and B.H. Jung (FIT); [JJ] 20 exs. Hwasun Gotjawal, Andeok-

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myeon, Seogwipo-si, 13.vi.2016, J.B. Seung and B.H. Jung, from Pleurotus pulmonarius ; 2 exs. Hwasun Gotjawal, Andeok-myeon, Seogwipo-si, 15.v.-6.vi.2016, J.B. Seung (FIT).

Host fungus: Pleurotus pulmonarius (Fr.) Quél.

Distribution: Korea (New Record), Japan, Russia (Far East).

Remarks: Triplax ainonia Lewis is rarely observed in Korea and is a mycetobiont (an obligatory fungal inhabitant). This species inhabits the fresh fruiting bodies of Pleurotus pulmonarius , which are soft and nearly ephemeral. Both adults and larvae usually feed on and breed in the context and the gills of fruiting bodies. In the laboratory, development from first larvae to adulthood took approxmately 30 days.

Figures

Figs. 1-2. Habitus(dorsal). 1. Triplax ainonia; 2. T. nagaoi.

Figs. 3-4. Genitalia (lateral, Each scale bar=0.1 mm). 3. T. ainonia; 4. T. nagaoi.

Figs. 5-6. Antenna (Each scale bar=0.1 mm). 5. T. ainonia; 6. T. nagaoi.