Anchylorhynchus vanini, Valente, Roberta De Melo & Medeiros, Bruno Augusto Souza De, 2013

Valente, Roberta De Melo & Medeiros, Bruno Augusto Souza De, 2013, A new species of Anchylorhynchus Schoenherr (Coleoptera: Curculionidae) from the Amazon, with a record of a new host palm for the genus, Zootaxa 3709 (4), pp. 394-400 : 395-399

Anchylorhynchus vanini sp. nov.

Figs. 1–2

Male ( Figs. 1 A, 2B–F). Length of pronotum + elytra: 4.9–7.0mm. Integument brown, densely covered by yellowishbrown, spatulate, non-overlapping scales, revealing punctures, especially along median line of pronotum; rostrum, head and scutellum dark brown and covered by scales smaller than on other dorsal surfaces; antennae, legs and ventral surface covered by pale setae. Rostrum 1.2–1.4 times as long as pronotum, with seven carinae (including the pair along scrobe) well-defined to base. Mouthparts: Mandibles slightly asymmetrical; apically with two distinct obtuse incisors; dorsally convex and with two long setae, ventrally concave and glabrous; molar region subtruncate, articular region slightly sinuate. Maxillae elongated, moving in vertical axis; mala with an anterior lobe, almost reaching apex of palpomere I, setation: apical region covered by numerous long setae, subapical region with a small projection and five spatulate setae, region adjacent to stipes with five long dorsal setae; palpiger with seven long lateral setae and ca. 15 dorsal short setae, ventrally glabrous; palpomere I 1.2 times longer than wide, with three setae on apicolateral edge of outer margin; palpomere II 1.6 times longer than wide, with three setae on apicolateral edge of outer margin; palpomere III 1.6 longer than wide, with one very small seta along inner margin and numerous apical sensilla; stipes with one very long lateroventral seta; cardo with four short lateroventral setae. Labium: prementum subquadrate, anteriorly concave, with dorsal region covered by numerous setae, lateral margin with ca. nine long setae; anterior tendon (ligula) elongate, narrow, sparsely covered by short setae; palpomere I as long as wide, with five long setae on centrolateral region (towards outer margin) and one ventral seta longer than three palpomeres together; palpomere II 1.4 times longer than wide, with two short setae on centrolateral edge of outer margin; palpomere III 1.6 longer than wide, with a very small seta along inner margin and numerous apical sensilla. Antennae: scape 1.2–1.3 times as long as funicle, reaching distal margin of eye; funicle: article I 1.2–1.3 times as long as article II, article II 1.3–1.4 times as long as article III; article III 1.4–1.5 times as long as article IV; articles IV–VI subequal in length; club four–articulated, with suture between apical articles indistinct, 3.3–3.4 times longer than wide. Pronotum trapezoidal, 2.1–2.4 times wider than long; covered by scales directed obliquely to center-apex on disc and backward on sides; anterior margin darkbrown and concave, without constriction (collar) in dorsal view; lateral margins, subparallel from base to middle, then convergent to apex, prominent and forming a strong acute angle with hypomerum in lateral view; posterior margin slightly bisinuate and as wide as humeri; scales longer in lateral and basal margins than on disc. Protibiae curved toward apex. Elytra 1.5–1.6 times longer than wide, 4.0–4.5 times longer than pronotum; wider in basal 1/2, lateral margins subparallel from base to middle, then slightly convergent to apex; epipleuron with inflexion well marked along interval IX, prominent and forming an acute angle with side in lateral view; humeri not prominent. Prosternum convex, densely covered by scales, anterior margin concave and with row of long scales, collar evident; hypomeron strongly concave; sternellum very narrow. Meso- and metasternum densely covered by scales on sides; metasternum in middle shining and with a concavity demarked by acute lateral margins. Ventrites shining, covered by fine sparse scales; ventrites I–II depressed in median region; posterior margin of ventrites II– IV straight; ventrite V trapezoidal, plane in median region, with subtruncate posterior margin. Aedeagus. Median lobe 2.8–3.0 longer than wide; dorsally convex; with subparallel lateral margins, slightly constricted in anterior region; distal margin rounded, with an obtuse median projection; orificial plates large, basal margin with sparse spiniform projections and curved sclerite with a bifid posterior projection. Apodemes of aedeagus 1.6–1.7 times as long as median lobe.

Females ( Figs. 1 B, 2A). Length of pronotum + elytra: 4.7–6.7mm. Females differ from males in having pronotal disc with a large dark brown triangular area, densely punctate, each puncture with a small seta; lateral areas of pronotum with integument paler than disc and covered by yellowish-brown spatulate scales. Pronotum more trapezoidal, with lateral margins parallel in basal 1/3 then strongly converging to apex, basal margin distinctly narrower than humeri, with a wider median process. Hypomeron less concave than in male. Protibiae straight toward apex. Elytra more round and convex. Metasternum convex. Ventrites I–II only slightly concave; ventrites III and IV narrower, retracted, separately angulate, with posterior margin of each segment distinctly projecting and bisinuate; ventrite V concave in median region. Body part ratios: length rostrum/length pronotum: 1.2–1.4 times; pronotum width/length: 1.9–2.1 times; elytron length/width: 1.4–1.5 times; length elytron/length pronotum: 4.4–4.8 times.

Variation. Rostrum from light-brown to red-brown, sometimes lighter in middle of dorsal region. Scales of head and scutellum sometimes very small, apparently lacking. Dark area of pronotal disc (♀) with color from dark brown to black. Punctures of elytral striae sometimes darker. Mandibular teeth vary from obtuse to acute. Setae may be decumbent in labium and maxillae.

Etymology. Named after Dr. Sergio Antonio Vanin, who mentored both authors and for his friendship and dedication to the study of Neotropical Curculionidae . As a side note, a species of Anchylorhynchus , A . bucki Vanin, happens to be the first species described by him.

Remarks. Anchylorhynchus vanini sp. nov. is very similar to Anchylorhynchus aegrotus Fahraeus and both can be easily distinguished from most other species of Anchylorhynchus by the elytra covered by completely yellowish brown scales and variably reduced scales on head and pronotum revealing the punctures. The yellow morphs of Anchylorhynchus variabilis Gyllenhal are further distinguished by having all the scales on the underside and epipleura transformed to hairs. The shape of the pronotum, very wide in males and with a distinct inflexion in females, is also shared between A. aegrotus and A. vanini sp. nov. Females can be distinguished from A. aegrotus by the dark area on the pronotum. Both males and females of A. vanini sp. nov. (4.7–7.0 mm) are generally larger than A. aegrotus (4.3–5.5 mm). The aedeagus of A. vanini sp. nov. is slightly wider at the apex, while it is slightly narrower in A. aegrotus . Finally, A. vanini sp. nov. is the only species of Anchylorhynchus with two long setae on the mandibles. Most species have only one long external seta, while A. tricarinatus has three setae. A. aegrotus is distributed along the Cerrado and Mata Atlântica biomes in Brazil, and has been collected only from Syagrus romanzoffiana (Cham.) Glassman , while A. vanini sp. nov. is distributed in the Brazilian Amazon and has been collected only from Syagrus vermicularis .

The key to the species of Anchylorhynchus provided by Vaurie (1954: 13–14) may be modified as follows to include the new species:

14 Beak from apex to front of eye at most 1.4 times as long as pronotum; pronotum in male at least twice as wide at base as long, in female narrower than elytra and with sharp angulation or tubercle on sides at middle; punctures on pronotal disc usually visible, especially along the median line.................................................................... 14a 14a Body length generally larger, 4.7–7.0 mm. Pronotum in male more trapezoidal and wider, 2.0–2.4 times wider than long, entirely covered by yellowish-brown scales; in female pronotal disc with distinct dark area covered by tiny setae. Median lobe with distal margin rounded and with an obtuse median projection. Mandibles with two long setae......... A. vanini sp. nov.

- Body length generally smaller, 4.3–5.5 mm. Pronotum in male less wide, 1.9–2.0 times wider than long; in both male and female entirely covered by large scales or covered by large scales in the sides and tiny setae in the disc; scales either uniformly yellowish-brown or forming a central longitudinal band of brown scales continuing in the scutellum and base of elytra. Median lobe with distal margin constricted. Mandibles with only one long external seta............................ A. aegrotus Natural history. Adults were collected by the first author in flowers of Syagrus vermicularis , locally known as “gueroba”. This palm is distributed in transition zones between Amazon forest and Cerrado in the Brazilian states of Pará, Tocantins and Maranhão, so it is likely that A. vanini sp. nov. is also found elsewhere. This is the first record of S. vermicularis as a host for a species of Anchylorhynchus . In the two localities studied, insects were also collected from flowers of Syagrus inajai (Spruce) Becc. and Syagrus cocoides Mart. , in addition to a number of others palms ( Acrocomia aculeata (Jacq.) Lodd. ex. Mart., Attalea maripa Mart. Aubl. , Attalea phalerata Mart. ex. Spreng., Astrocaryum vulgare Mart. , Mauritia flexuosa L. f. and Oenocarpus distichus Mart. ). Specimens of Anchylorhynchus vanini sp. nov. were only found in S. vermicularis , suggesting that the association is specific at least locally. Besides, supporting the specificity o the association, A. vanini sp. nov. was not collected in similar studies conducted elsewhere in the Brazilian Amazon where S. vermicularis was not recorded: Caxiuanã, Pará ( Valente 2000), Querência, Mato Grosso ( Valente & Guimarães 2010) and in the region of the middle Xingu River in a number of palms ( Syagrus cocoides , Syagrus inajai , Attalea maripa , Attalea phalerata , Astrocaryum gynacanthum Mart , Astrocaryum aculetum G Mey , Astrocaryum murumuru Mart. , Astrocaryum paramaca Mart. , Astrocaryum vulgare Mart. , Bactris acanthocarpa Mart. , Bactris brongniartii Mart. , Bactris campestris Poepp. ex Mart. , Euterpe longebracteata Barb. Rodr. , Euterpe oleracea Mart. , Geonoma maxima (Poit.) Kunth , Mauritia flexuosa , Mauritiella armata (Mart.) Burret , Oenocarpus distichus and Socratea ezorrhiza (Mart.) H. Wendl. ).

Geographical distribution. Lowland rainforests, in open forests in Pará (Canaã dos Carajás and São Geraldo do Araguaia), Brazil, in elevations ranging from 210 to 500 m.

Type material. Holotype male deposited in MPEG: “ Brasil –PA–Canaã dos Carajás\ Projeto Níquel Vermelho\ -6°28’32”/-49°52’27”\ 27–XI–2005 \ R.M Valente col. [label 1], Em inflorescência de\ Syagrus vermicularis \ amostra 0 3 [label 2]”. Paratypes: same as holoype (15 ♂ [2 dissected], 15 ♀ UFPA; 1 ♂, 1 ♀ MZUSP); same as holoype but, “amostra 01”(9 ♂, 16 ♀ UFPA; 2 ♂ MZUSP, 3 ♂, 3 ♀ CMNC); “amostra 02” (1 ♀ MPEG; 1 ♂ MZUSP); same as holoype but, “ 02–V–2004, amostra 01” (4 ♂ MPEG); “ 07–V–2004, amostra 02” (2 ♂, 2 ♀ [1 dissected] UFPA); “ 26–VIII–2004, amostra 01” (3 ♂, 1 ♀ MPEG) “ 25–XI–2005, amostra 01”(2 ♂, 7 ♀ MPEG); “ 25–XI–2005, amostra 03” (3 ♂, 4 ♀ MPEG), “ 25–XI–2005, amostra 04” (11 ♂ [1 dissected], 8 ♀ UFPA; 1 ♀ MZUSP); “ 25–XI–2005, amostra 05” (2 ♂, 3 ♀ AMNH); “ 25–XI–2005, amostra 06” (2 ♂, 2 ♀ MPEG); “ 25–XI– 2005, amostra 07” (1 ♂, 1 ♀ MPEG); “ 25–XI–2005, amostra 08” (4 ♀ [1 dissected] UFPA; 2 ♀ MZUSP). “ Brasil – PA–São Geraldo do Araguaia\ Serra das Andorinhas\ Fazenda do Cunha, Córrego Jatobá\ 25–X–2011 [label 1], Em inflorescência de\ Syagrus vermicularis \ amostra 0 1, 9:00 horas\ Guimarães, J.R. Col”. [label 2] (1 ♂, 2 ♀ UFPA); same date but, “amostra 0 2, 9:27 horas” (1 ♂, 4 ♀ MPEG); “amostra 0 3, 9:48 horas” (1 ♂, 4 ♀ MPEG); “amostra 0 4, 10:10 horas” (1 ♂, 2 ♀ MPEG); “ 28–X–2011, amostra 0 5, 10:12 horas” (1 ♂, 1 ♀ UFPA).

Figures

FIGURE 1. Anchylorhynchus vanini sp. nov., habitus, dorsal, lateral and ventral view. A Male, Holotype. B Female, Paratype, MZUSP. Scale bars: 2 mm.

FIGURE 2. Anchylorhynchus vanini sp. nov. A Female mandibles, dorsal view. B – F Male: B Mandibles, dorsal view. C Maxilla, dorsal view. D Labium, dorsal view. E Aedeagus, dorsal and lateral view. F Pronotum (arrows indicate the direction of the scales). Scales bars: A – D, 2 µ; E, 0.01 mm, F, 1 mm.