On the mysterious Hylobius huguenini Reitter , 1891 ( Coleoptera : Curculionidae : Molytinae )

During verifi cations of museum material for the Catalogue of the Palaearctic Coleoptera, the type specimen of Hylobius huguenini Reitter, 1891 conserved in the Hungarian National Museum was examined. The type specimen had been found by Gustav Huguenin in the Emmental region in Switzerland. The species was never found again and remained therefore mysterious. After the examination of the type specimen, it became clear that Hylobius huguenini belongs to the American genus Heilipodus Kuschel, 1955 (comb. nov.), and there it ranks as a good species next to Heilipodus goeldii sp. nov., described here, and H. polyspilus (Pascoe, 1889), both from Brazil. The type specimens of Heilipodus goeldii sp. nov. were found in the Emil August Göldi-collection in the Natural History Museum of the Burgergemeinde Bern.


Introduction
Hylobius huguenini Reitter, 1891 was described, based on a single female specimen from the Emmental, a region from hilly to mountainous altitudes between the cantons Berne and Lucerne on the northern side of the Swiss Alps.The species was never found again, and therefore its identity remained mysterious.It was included in the Fauna Coleopterorum Helvetica by Stierlin (1898) in the World Catalogue by Dalla Torre & Schenkling (1932), and as a doubtful record also in the checklist of the Swiss weevils (Germann 2010).It was previously stated that -based on pictures of the type specimen -the specimen is more similar to the American species of the genus (Germann 2011).
During the re-examination of species names for the catalogue of Palaearctic Coleoptera, Miguel Alonso-Zarazaga (Madrid, Spain) asked me to unravel this mystery, and as a highly endemic Hylobius restricted to the Emmental-region is very unrealistic, I suspected a misplaced specimen.When Gustav Huguenin, a Swiss internist and pathologist , collected the specimen on which Reitter (1891) based his description, exhaustive plantations of mostly North American conifers were made around the Entlebuch, a subregion of the Emmental.As Huguenin visited Bad Weissenburg in the Simmental several times in the years 1885-1903(Lätsch 1991)), he could have collected the specimen during this time, probably visiting his relatives at Krauchtal, where he was born.So a promising track to solve the mystery, was to check for misplaced Holarctic members of the genus Hylobius Germar, 1817.But after comparing specimens of North American Hylobius from NHM and NMNH, previously identifi ed as such based on the key by Warner (1966), with the type specimen of H. huguenini, this track proved to be wrong.The detailed and critical re-examination of the type fi nally revealed that H. huguenini belongs to the genus Heilipodus Kuschel, 1955 (new combination).In comparison with specimens from the Emil August Göldi-collection (NMBE), H. huguenini comb.nov. is closely related to H. goeldii sp.nov.described below, and both species are similar to Heilipodus polyspilus (Pascoe, 1889) from Brazil

Material and methods
Photographs were taken with a 5-megapixel digital camera (Leica DFC 420), the genitalia were photographed in glycerine.Series of images were captured through a binocular (Leica MZ16) and processed by an Auto-Montage software (Imagic Image Access, Version 8).All measurements were taken digitally with the measurement-tool of the above mentioned Auto-Montage software.

Remark
The type specimen is in a relatively good condition, the tarsal segments 2-5 of the right hind leg are missing as well as the onychium of the left fore leg.The specimen is slightly immature; this explains its light reddish-brown colour.
VESTITURE.Body, head and legs covered with elongated, oval, yellowish scales of variable width.Tips of broader scales truncated.Frons covered with broader scales.Scarcely standing scales restricted to fi rst fi fth of rostrum.Pronotum with broader scales forming lateral bands at each side just before humeral calli of the elytra.Surrounding scales thinner.Elytra with broader and thinner scales patchily arranged, and forming short bands at base of the 3 rd and especially 5 th interstriae.Broader scales are denser just behind second half of elytra, forming a diffuse transverse banding.Scutellum very densely covered with overlapping whitish broader scales.
HEAD. (Fig. 1E) Globular, rostrum 3.5 times as long as wide, eyes oval and fl at.Interocular distance half as wide as base of rostrum.Rostrum narrowest in its middle, widened to apex to about the size at base.PRONOTUM.(Fig. 1A, C) Transverse (L/W = 0.7), widest just behind the middle, strongly constricted towards fore margin, densely tuberculate and transversely wrinkled, carinate in the middle, tubercles glossy.Slightly curved in lateral view.Base weakly sinuate, bulged towards scutellum.
ELYTRA.(Fig. 1A, C) Elongate (L/W = 1.8), parallel sided.Base sinuate.Shoulders well pronounced, slightly convex at disc in the middle.Elytra strongly constricted before their last fi fth, therefore convex on each side before elytral declivity; apex fl attened in lateral view.Striae linear and regularly punctate, interstriae about as wide, convex and glossy.Striae and interstriae weakly blurred by transverse wrinkles.
LEGS.Strong, all femora strongly dentate, tibiae sinuate at inner side, apex with long curved uncus at inner angle.Tips of tibiae in-and outside (ventrally and dorsally) with apical combs, bristles light brown; dorsal row of the apical comb of hind tibiae composed of more than two bristles in parallel.Four visible tarsal segments, 1 s t segment 1.5 times longer than 2 nd , 3 rd of about the same length, twice as wide, 4 th segment tiny, 5 th reaching twice as far as 3 rd .Claws simple.

Type locality
Brazil, Pará, Obidos (Amazon Basin).VESTITURE.Body, head and legs covered with elongated, oval, yellowish scales of variable width.Tips of broader scales truncated.Eyes encircled with broader scales.Scarcely standing scales restricted to fi rst fi fth of rostrum.Pronotum with broader scales forming lateral spots at each side just before humeral calli of the elytra.Surrounding scales thinner.Elytra with broader and thinner scales patchily arranged, and forming spots at base of the 3 rd and especially 5 th interstriae.Scutellum very densely covered with overlapping whitish broader scales.HEAD.(Fig. 1F) Globular, rostrum 3.5 times longer than wide, eyes oval and fl at.Interocular distance half as wide as base of rostrum.Rostrum narrowest in or just behind its middle, widened to apex to about the size at base.Rostrum striate and weakly punctate on its fi rst half; only faintly punctate and glossy towards apex.Antennae inserted behind last third of rostrum; scrobes from the anterior margin of the eyes apicalwards.Scrobes visible from above from the middle of the rostrum to the ELYTRA.(Fig. 1B, D) Elongate (L/W = 1.6-1.7),widest in fi rst third.Base sinuate.Shoulders well pronounced, slightly convex at disc in the middle.Elytra constricted before their last fi fth, therefore convex on each side before elytral decline; apex fl attened in lateral view.Striae more or less linear and punctate, interstriae about as wide, convex and glossy.Striae and interstriae blurred by coarse transverse wrinkles.
LEGS.Strong, all femora strongly dentate, tibiae sinuate inside, apex with long curved uncus at inner angle.Tips of tibiae in-and outside (ventrally and dorsally) with apical combs, bristles light brown; dorsal row of the apical comb of hind tibiae composed of more than two bristles in parallel.Four visible tarsal segments, 1 st segment 1.5 times longer than 2 nd , 3 rd of about the same length, twice as wide, 4 th segment tiny, 5 th reaching twice as far as 3 rd .Claws simple.

Sexual dimorphism
Weak, last ventrite of the male specimen bulged in the middle, rostrum of the male more coarsely striate.

Differential diagnosis
Very close to H. huguenini comb.nov., differences are as follows: i) eyes encircled with scales; ii) habitus more robust, elytra broader; iii) scales more spotted, not forming transverse bandings; iv) striae and interstriae more blurred by coarse transverse wrinkles; v) scales forming lateral spots on pronotum instead of bandings; vi) median carina on pronotum less pronounced; vii) ventrites more transverse; viii) female genitalia different (Fig. 2G-L).Both species are similar to Heilipodus polyspilus (Pascoe, 1889) (a single male specimen with the following indications was examined: "Brasilien, Porto Alegre, X.-XII.58K.E. European Journal of Taxonomy 20: 1-8 (2012) Hüdepohl" coll.Frey, NMBA) in their general habitus, but differ by i) the much less coarsely tuberculate pronotum, by ii) the indistinct third interstriae on the elytra, which are broadened and elevated in H. polyspilus, by iii) the light brown bristles of the apical combs of tibiae, and by iv) the male genital organs (Fig. 2D-F), note that the male of H. huguenini comb.nov. is unknown.

Discussion
The genus Heilipodus was established by Kuschel (1955)  Based on these characters, H. huguenini belongs to the genus Heilipodus (comb.nov.) and with its spotty pattern it is similar to H. goeldii sp.nov.and to H. polyspilus.All three species belong to the more discretely coloured species of the genus.After the author's investigations H. huguenini comb.nov. is a valid species within the genus Heilipodus.The original areal is most likely somewhere in South America, and based on its similarity to H. goeldii sp.nov., probably in the Amazon Basin.However, it remains mysterious as to how a specimen of this presumably Neotropical species found its way to the Emmental region in Switzerland.International trading is known around Burgdorf, which could have raised the chance of introduced specimens travelling along with goods.Also a mislabelled specimen or an accidentally misplaced specimen during exchange of material by Huguenin (or Reitter) with colleagues cannot be excluded.However, the starting hypothesis that the specimen was introduced together with pine trees from North America can be rejected.
Institute of Biogeography, University of Basel) and Geiser (NMBA) for transmitting the type specimen.I am thankful to two anonymous referees for their valuable comments on the manuscript.
Rostrum striate and weakly punctate on its fi rst half; only faintly punctate and glossy towards apex.Antennae inserted after last third of rostrum; scrobes from the anterior margin of the eyes apicalwards.Scrobes visible from above from the middle of the rostrum to the apex.Antennal scape reaching base of rostrum.Funicular segments as follows: (L/W): 1 Reitter, 1891eldii sp.nov.paratype,ditto.GERMANN C., On the mysterious Hylobius hugueniniReitter, 1891 (Riding 1983)bmer 1982)the species formerly belonging to Heilipus Germar, 1824.The genus HeilipodusKuschel, 1955 is distributed, according to  Wibmer & O'Brien (1986), in South America with 87 species (including the present ones transferred and described), while 36 species are known from Central America(O'Brien & Wibmer 1982).No species are known from North America.Concerning their lifestyle, as far as it is known, Heilipodus are stem borers of various plants.Larvae and pupae of H. erythropus (Klug, 1829) were collected byRosado-Neto (1980)in Brazil (Paraná) from Eryngium L. (Apiaceae).Another species -Heilipodus intricatus (Boheman, 1836) -was used in Australia as potential biological control organism against the invasive Baccharis halimifolia L. (Asteraceae) from the USA(Riding 1983).