Amasa parviseta Knížek & Smith, 2024

Knížek, Miloš & Smith, Sarah M., 2024, A new widely distributed invasive alien species of Amasa ambrosia beetles (Coleoptera: Curculionidae: Scolytinae: Xyleborini), Zootaxa 5403 (3), pp. 385-390 : 386-388

Amasa parviseta Knížek & Smith , new species

http://zoobank.org/ urn:lsid:zoobank.org:act:71D2B606-9E48-41E0-A86B-C6B874D1F903

Figs 1–5

Type material. Holotype, female, AUSTRALIA: 35.30S 150.24E, NSW [New South Wales], Bawley Point , 5 April 1997, D.C.F. Rentz ( ANIC). Paratypes, AUSTRALIA: 1 female, ACT [Australian Capital Territory] Black Mt. light trap, 4.iii.[19]68, M.S. Upton ( ANIC) ; 1 female, 35.16S 149.06E, Black Mtn. nr. light trap, 12 Sept. 1994, T. Weir & W. Dressler, ANIC 1910 , Berlesate, dry Eucalyptus litter ( ANIC) ; 1 female, [Queensland], Brisbane, Banyo , Kennedy’s Timber , 8 Aug 2006, W. Roe, in static trap 1514, MSUC_ARC_5000 ; 1 female, N. Qld , 31-X-1986, J.D. Brown, light trap ( QM) ; 1 female; 7 km NE of Tolga, Feb 1988, Storey & De Faveri, light trap ( QM) ; 1 female, as previous except: Dec 1988, NHMUK014189218 ; NSW [New South Wales] Wentworth Falls , 13.i.1955, K.M. Moore, ex E. piperita ( ANIC) . FRANCE: 2 females, Villa Thuret, Antibes , summer 2021, 7,125216 E, 43,563919N, MK coll., 6 females, Paradou Park , Cannes , summer 2021, 7,05809 E, 43,56056 N, MK coll. ; SPAIN: 15 females, Pontevedra, Vilagarcía de Arousa , “ Monte Xiabre “, 17. IV. 2008, Lindgren trap, in Eucalyptus globulus and Pinus pinaster mixed stand, MK coll. ; BRAZIL: 2 females, SP [São Paulo], Lençóis Paulista, Duratex S.A. , α-pinene + ethanol baited multiple funnel FIT, Eucalyptus grandis stand, Flechtmann, C.A.H. coll, 02/III/2007, MSUC_ ARC_321578 , MSUC_ARC_321579 ; URUGUAY: 3 females, Tacuarembo ́, Estación Experimental La Magnolia , 31°42’49.27” S, 55°49’20.95” W, June 2015, D. Gomez, extracted from basal area of dying Eucalyptus grandis, MSUC_ARC_320246 , MSUC_ARC_320247 , MSUC_ARC_320248 .

Diagnosis. 2.38–3.00 mm long (n = 35); 2.06–2.40× as long as wide. The species is distinguished by the pronotum appearing basic (type 2) when viewed dorsally, anterior margin serrate; declivity slightly convex, surface shining, smooth, nearly glabrous; declivital interstriae 1–4 multiseriate granulate, granules confused; and declivital interstriae convex.

Similar species. Amasa truncata , A. resecta , A. versicolor (Sampson)

Description (female). 2.38–3.00 mm long (n = 35) (2.70 mm in HT); 2.06–2.40× as long as wide (2.25× in HT). Body usually bicolored: pronotum, head, legs, antennae and abdomen light brown, elytra darker. Head: epistoma entire, transverse, with a row of hair-like setae. Frons weakly convex to upper level of eyes; surface strongly shagreened, impunctate, granulate; granules slightly longitudinal, rounder, denser above epistoma, increasing in size and length and decreasing in density dorsally and laterally; whole surface with very sparse, fine and rather long hair-like setae, their length similar to the maximum width of eyes. Eye emarginate to half its width just above antennal insertion, upper part smaller than lower part. Submentum triangular, deeply impressed. Antennal scape as long as club. Pedicel as wide as scape, shorter than funicle. Funicle 4-segmented, segment 1 shorter than pedicel. Club approximately circular and flat, type 4; segment 1 corneous, transverse on anterior face, occupying basal 1/4; segment 2 narrow, larger than segment 1, corneous; segments 1–3 present on posterior face. Pronotum: 0.93–1.17× as long as wide (1.04 in HT). In dorsal view basic and parallel-sided, type 2, sides parallel in basal 1/2, rounded anteriorly; anterior margin with a row of 10–14 serrations. In lateral view basic, type 0, disc flat, summit at midpoint. Anterior slope shagreened, shining, with densely spaced, fine transversal asperities, becoming lower, smaller and denser towards summit, bearing long, fine, semi-recumbent, hair-like setae. Disc shiny, shagreened, sparsely fine punctate in posterior part, sparsely granulate in anterior part to the summit, with microscopic hair-like setae. Lateral margins obliquely costate. Base transverse, posterior angles broadly rounded. Elytra: 1.14–1.44× as long as wide (1.21× in HT), 1.00–1.50× as long as pronotum (1.16× in HT). Scutellum moderately sized, broad, linguiform, flush with elytra, flat, shiny. Elytral base transverse, edge oblique, humeral angles rounded, parallel-sided in basal 3/4, then sharply angulate to apex. Disc ascending posteriorly, shiny, with very short fine semirecumbent hair-like setae in punctures; striae and interstriae laterally diverging from base to declivital summit; striae not impressed, punctures separated by two diameters of a puncture; interstriae flat, finely punctate, punctures fine, up to 1/2 the size of strial punctures, uniseriate, becoming confused and biseriate posteriorly. Declivity truncate, face slightly convex, smooth, shining, nearly glabrous; three striae present, striae moderately impressed, especially the first one, the third one evenly curved laterally in the middle and more distant from the others, strial punctures shiny, very large, shallow, with visible bottom, much larger than on disc, punctures subcontiguous to separated by one diameter of a puncture; interstriae smooth, semishining, impunctate, convex, sutural interstriae narrower than others, interstriae 1–4 multiseriate granulate, granules strongly confused, biggest on the interstriae 1 and 2, becoming smaller and sparse on lateral interstriae, bearing very fine and short microscopic hair-like setae. Posterolateral margin forming a circumdeclivital carina, carina almost glabrous, with very fine and short microscopic sparse hair-like setae. Legs: procoxae contiguous; prosternal coxal piece bulging. Protibiae slender, broadest at apical 1/3; posterior face inflated, coarsely granulate; apical 1/2 of outer margin with 6–8 small socketed denticles, their length as long as basal width. Meso- and metatibiae broad, flattened, outer margins evenly rounded with 10 small and nine small to minute socketed denticles, respectively; posterior faces unarmed; anterior faces finely granulate.

Differential diagnoses. The species is the morphologically most similar to Amasa truncata , from which it differs mainly in the form of the elytral declivity, which is “hairy” in A. truncata with hair-like setae of nearly equal length present in all interstriae of declivital face and also on the posterolateral circumdeclivital carina, these are rather long, longer than the diameter of the strial punctures on the declivity. Granulation of the declivital interstriae is not so conspicuous or abundant as in the new species. Amasa resecta is remarkably bicolored with light pronotum and dark elytra and has dull glabrous elytral declivity with sparse granules on declivital interstriae, which are completely missing on interstriae 4. Amasa versicolor has also dull elytral declivity and with short hair-like setae on both the interstriae and on the posterolateral circumdeclivital carina (interstrial setae shorter than in A. truncata ).

Etymology. L. parvi = small, L. seta = hair, in reference to the nearly glabrous elytral declivity and its posterolateral carina, with microscopic fine setae only, contrary to the morphologically most similar species A. truncata .

Distribution. Australia (Australian Capital Territory, New South Wales, Queensland). Europe: France (incl. Corse, A. Roques pers. comm.), Portugal, Spain. South America: Argentina (Tucumán), Brazil (Minas Gerais, São Paulo), Chile (Valparaíso), Uruguay.

Host plants. Specimens were collected from Eucalyptus piperita and Eucalyptus leaf litter in Australia and Eucalyptus in Chile, Uruguay and France ( Gómez et al. 2017; Kirkendall 2018, A. Roques pers. comm.), otherwise all known specimens were collected in traps located in areas of Pinus and Eucalyptus trees.

Remarks. This species was initially determined to be Amasa truncata in the following publications: Cognato & Flechtmann (2011), Gómez et al. (2017), Raihno et al. (2018), Kirkendall (2018); Amasa resecta ( Viñolas & Verdugo 2011) ; Amasa near truncata in Barnouin et al. (2020); and Amasa sp. in Marchioro et al. (2022) and Córdoba et al. (2023).

Figures

FIGURES 1–5. Amasa parviseta paratype female from Ponteverda Spain (MK collection) 1) habitus dorsal view; 2) habitus lateral view; 3) elytral declivity part; 4) elytral declivital face; 5) lateral detail of elytral declivity with microscopic hair-like setae visible on the lateral edge of the declivity and on the apices of tubercles on the declivital face. Photographs by Antonín Knížek.