Redescription of the forgotten New Caledonian weevil genus Callistomorphus Perroud, 1865 (Coleoptera, Curculionidae, Eugnomini) with descriptions of eight new species

Abstract Callistomorphus is one of the “forgotten” genera of the tribe Eugnomini inhabiting rain forest in New Caledonia. In this paper, the genus Callistomorphus and the type species C.farinosus are redescribed. Eight new species, Callistomorphusfundatussp. n., C.gibbussp. n., C.malleussp. n., C.minimussp. n., C.rutaisp. n., C.szoltysisp. n., C.torosussp. n. and C.turbidussp. n., are described, originating from the main island of New Caledonia. Illustrations and SEM photographs of the external morphology and the male and female terminalia are provided, as well as dorsal habitus colour photographs of the adults, a key to the species, a distribution map, and a discussion of the systematic position of Callistomorphus within the tribe.


Introduction
For many years, only three genera of Eugnomini from New Caledonia were known: Pactola Pascoe, 1876, with two species (a third was synonymised by Mazur (2014)), originally placed in the genus Macropoda Montrouzier, 1861 (see Mazur 2014); in Marshall's key and, according to the original description of Perroud, very similar to Stephanorrhynchus White, from which it differs by the fact that its rostrum is three times, not twice, as long as the head". May (1993) analysed in detail the morphology of the larvae from six genera of Eugnominae and revised the status of the subfamily to a tribe with two subtribes -Eugnomina Lacordaire, 1863 andMeriphina Marshall, 1937. This state of affairs was confirmed by Alonso-Zarazaga and Lyal (1999).
In this paper, a redescription of the genus Callistomorphus is presented, as well as descriptions of eight new species from New Caledonia, along with a key to all the species within the genus and comments about the taxonomic position of the genus within the tribe.

Materials and methods
This study is based on 26 specimens. Holotypes are deposited in the Muséum National d'Histoire Naturelle, Paris (MNHN). Paratypes are deposited in the Museum of Natural History, University of Wrocław, Poland (MNHW) and in the Natural History Department of Upper Silesian Museum, Bytom, Poland (USMB).
Measurements were made using a calibrated stereomicroscopic grid eyepiece (C-W10xB/22) in a Nikon SMZ-800 stereomicroscope. Genitalia preparations were made according to the standard method of macerating the separated abdomen for 5-10 min in a warm KOH solution. After dissection, if necessary, terminal structures were stained with a solution of Chlorazol Black E in glycerine for 5-10 min under visual control. Habitus photographs were taken using a Canon Power Shot A640 camera connected with the stereomicroscope and processed using the Helicon Focus v. 4.50 and Photo-Filtre v. 6.1 software programmes. All drawings were made by using the Corel Draw package. Scanning electron micrographs were taken using a Hitachi S-3400N.
The nomenclature of the male terminalia and abbreviations of particular measurements (partly modified) follows Wanat (2001): al abdomen length (measured through the middle of ventrites); apw pronotum width at anterior margin; arw width of rostrum apex; aw abdomen maximum width; bew width of elytral base (measured through the middle of humeral calli); bpw pronotum width at the base; el elytra length (measured in top view in a position when the base and apex of elytra are at the same level); eyl eye length (measured in top view, when the head is positioned horizontally); frw minimum frons width; hl head length (measured in top view, from anterior edge of pronotum to fore margin of eyes); hw head width (measured across the middle of the eyes); lb length of body exclusive of rostrum; lvl last ventrite length (measured through the middle); lvw last ventrite maximum width; mpw minimum pronotal width; pl pronotum length (measured through the middle); rl rostrum length, measured in dorsal view, when base and apex of rostrum are at the same level; scl antennal scape length.
All dimensions are given in millimetres.

Diagnosis.
Distinguished from other genera of Eugnomini by the following combination of characters: rostrum elongate, longer than pronotum alone, but shorter than head and pronotum taken together; in dorsal view with distinct, polished longitudinal carina. Mandibles elongate, distinctly protruding beyond apical margin of rostrum, not exodont, overlapping. Head behind eyes distinctly constricted. Pronotum strongly narrowed before apical part with pair of various developed tubercles near middle of length. Elytra strongly scabrous with numerous, small tubercles and pair of large, elongate tubercles near middle of length (next as "middle tubercles"). Legs elongate, all femora strongly broadened, with distinct, enlarged tooth that is usually larger than half of maximum femoral width; all tibiae distinctly sinuate, without mucro in male; tarsal claws free at base, glabrous, only regularly extended basally.
Redescription. Body length (lb) -7.20-14.70 mm. Body colour and vestiture . Entire body covered with strictly adjoining, small, elongate scales. Colour variable but general patterns appear stable in some species (e.g. C. farinosus Perroud). Middle of elytra usually with paler spot between the 7 th and 11 th elytral intervals and usually extending from one-third to two-thirds of elytral length, though sometimes shorter.
Elytra . Longer than wide (el/bew 1.47-1.68) with eleven intervals. Widest at base, through the middle of well-developed humeral calli; lateral margins subparallel to ca. fourth-fifths of length before strongly narrowing to apex. Third interval, near middle of length, with distinct tubercle (except C. minimus sp. n.); height of the tubercle subequal to width of two or three intervals, the length more or less from one-third to one-quarter length of elytra. Intervals convex, in some species intervals 3, 5, 7, 9 more convex with numerous, irregular, small tubercles (flattened or acuminate). Seventh interval narrowed on short distance behind humeral angles, apically with more or less distinct tubercle (next as -posterior calli), protruding beyond outline of elytra in dorsal view (except C. minimus sp. n.); 9 th interval behind humeral angles weakly protruding, clearly visible in dorsal view on this section.
Tegmen . With elongate apodeme, parameroid lobes divided in different ways (detailed in description of species).
Spiculum gastrale . With elongate apodeme and divided base. Hemisternites strongly sclerotised, in most species directly connected with base of spiculum.
Distribution. The genus is endemic in New Caledonia, known only from the main island, Grande Terre. Localities where particular species were collected are shown in Fig. 145.
Biology. The detailed biology of species is unknown. Although other members of Eugnomini have been reared from dead wood, subcortical tissues, live stems, galls, and the leaves or fruits of many species of plants from different families (e.g. May 1987, specimens of Callistomorphus were collected by beating or by sifting from the litter. Many species are suspected to have nocturnal activity, often being collected using light traps or by beating vegetation at night (see the data from the labels). According to the label data and the personal comments of Marek Wanat, members of the genus are most commonly found on plant leaves in humid and rain forest growing on limestone and/or ultramafic rocks (Bonvallot et al. 2013), some of them only at altitudes exceeding 500 metres above sea level.
Remarks. Members of the genus are variable in terms of their size, body proportions and colour. However, they are separated from the other genera of the tribe by the set of characters presented in the above diagnosis. Many of the species are also the biggest members of the tribe. Despite their large size and characteristic body form, members of this genus are not common in museum collections or in the field. For example, during the French fieldwork conducted in the 1980s and 1990s, where fogging and standard collecting methods were used (pers. com. Hélène Perrin), no single specimen of Callistomorphus was found (see the label data of the specimens deposited in MNHN); fewer than 30 specimens of the genus were recently collected during three Polish expeditions (2006, 2008 and 2010) where a wide range of collecting methods (beating vegetation at night and day, sifting, sweep netting, light traps) were used. Most of these specimens represent new species which are described in this paper. Figures 1,4,13,22,31,40,49,58,67,76,85,94,101,108,115,122,127,132,135,140 Callistomorphus farinosus Perroud, 1865: 170, pl. 1, fig. 7 Diagnosis. The largest member of the genus. Last three antennomeres of funicle wider than long. Apical margin of pronotum widely concave medially in dorsal view. Elytra with characteristic whitish spot in the area from medial tubercles to 7 th intervals, not reaching apical part. Penis body distinctly, regularly narrowed from base to apex in lateral view. Parameroid lobes of tegmen slightly divided apically. Female abdominal tergite VIII with maximum width near middle. Redescription. Body length (lb) -12.80-14.70 mm. Body colour and vestiture (Fig. 13). As stated in diagnosis, whitish spot on elytra is clearly visible on generally darker ground coloration. Some specimens with T-or X-shaped blackish spot on elytra, extending from base to medial tubercles. Pronotum with distinct, light, oblique lines. All studied additional specimens also with distinctly lighter hind legs than lectotype. Darker area at apical part of elytra sometimes with transverse stripe of paler scales.
Male terminalia (Figs 94,108,115). Penis body little longer than apodemes; in dorsal view slightly narrowed to rounded apex; in lateral view distinctly curved at base; regularly narrowing apicad; apodemal bridge weakly sclerotised. Endophallus everted without visible sclerites. Parameroid lobes of tegmen divided apically, with similar length as apodeme. Spiculum gastrale with hooked basal piece. Hemisternites on spiculum gastrale irregular, small, strongly sclerotised. Female terminalia (Figs 122,127,132,135,140). Apodeme of sternite VIII with separate basal part; apical lobe with characteristic shape of sclerotisation occupying medial area. Abdominal tergite VIII slightly broadened from base to more or less middle of length, remainder of tergite VIII distinctly narrowed to rounded apex; lateral margin with elongate setae. Spermatheca as in Fig 132. Pygidium with maximum width at base, distinctly narrowed to rounded apex. Ovipositor with relatively small gonocoxite; apical setae short; vagina stout.
Measurements Remarks. Kuschel selected a female specimen from Perroud's original series as a syntype in 2004 but this action was never published. To ensure stability in nomenclature and to clarify identity of this species I herein designate the same female specimen as the lectotype. I take this action under the article 74.1 of the Code (ICZN).
Elytra (Figs 23,32). Elongate (♂: el/bew = 1.65). Slightly narrowed from humeral calli to apical part. Medial tubercles distinct, higher than width of its base on 3 rd interval. Striae with single line of suboval punctures. Odd intervals with distinct, toothshape, tubercles with elongate, slightly hooked, single scale on the top. Tubercles on 7 th intervals conspicuous, protruding from outline of elytra in dorsal view. Scutellum distinctly elongate, ca 1.5 × as long as wide.
Male terminalia (Figs 95,109,116). Penis body distinctly longer than apodemes; almost subparallel from base to apical part, apically slightly narrowed to rounded apex; basal part partly sclerotised, except medial area; in lateral view distinctly, regularly curved, apically slightly upturned. Internal sac longitudinally crinkled, without any apparent structure or sclerites. Parameroid lobes of tegmen slightly shorter than apodeme, divided almost to base; the dorsal part of the tegminal ring with membrane and sharp, protruding process. Tegminal apodeme apically extended. Spiculum gastrale robust, slingshot-shape, apically strongly sclerotised; in lateral view apodeme apically curved; hemisternites fused with base of spiculum.
Female Etymology. This epithet is derived from the Latin word "funda" (slingshot) and refers to the shape of spiculum gastrale. A variable adjective.
Remarks. Only one specimen of this new species has been found within the studied collections. A set of characteristic features, including the almost uniform brown colour, elongate elytra and last ventrite, as well as terminal structures, indicates that this is a new species.
Description. Body length (lb) -7.90-9.60 mm. Body colour and vestiture (Fig. 15). Generally dark brown with various, irregular spots of different shades of brown. Legs in some specimens with mottled coloration, from whitish to variable shades of orange and almost black. Tibiae generally paler, more or less orange. Pronotum sometimes with darker spots near base, medially and with pair of narrow, oblique stripes of white-yellow scales from hind angles to middle of length.
Male terminalia (Figs 96, 110, 117). Penis body slightly longer than apodemes; from base to apical part almost subparallel, apically slightly narrowed to rounded apex; basal part sclerotised, except medial part; distinctly, regularly curved in lateral view, apices thin and distinctly upturned. Internal sac without any structure or sclerites. Etymology. This epithet is the Latin noun "gibbus" (protuberance, hump) and refers to a pair of large tubercles on elytra. A noun in apposition.
Remarks. The shape of pronotum together with the lateral profile of the rostrum are characteristic for this new species. The terminalia are quite similar to C. fundatus sp. n. but differ in the shape of the apex of the penis (in dorsal view more rounded, in lateral view more upwardly directed in C. gibbus sp. n.). One small specimen was quite similar to C. turbidus sp. n. in bodily proportions, but distinctly different in the shape of the pronotum, rostrum length and form of terminal structures.
Description. Body length (lb) -8.60-10.50 mm. Body colour and vestiture (Fig. 16). Colour variable, from dark brown to yellowish. Some specimens with whitish coating on apical and lateral parts of elytra. Similar, pale coating, in some specimens, also covered hind femora. Pronotum with longitudinal yellowish stripes.
Male terminalia (Figs 97,111,118). Penis body slightly longer than apodemes; from base to apical part almost subparallel, apically slightly narrowed to rounded apex; basal part sclerotised, except medial area; in lateral view distinctly, regularly curved, apically expanded into small tubercles. Internal sac without any structure or sclerites. Parameroid lobes of tegmen thin, distinctly shorter than apodeme, divided almost to base and surrounded by thin membrane. Tegminal apodeme apically extended. Spiculum gastrale robust, apodeme laterally flattened, distinctly bent distally; hemisternites fused with base of spiculum.
Measurements. ♂: al 3.50-4.00, apw, 1.  Etymology. This epithet is derived from the Latin noun "malleus" (hammer) and refers to the shape of female sternite VIII. A noun in apposition.
Remarks. The species is variable in size and colour but easily distinguished by the elongate elytra with relatively small medial tubercles and weakly curved rostrum. Also, penis and female sternite VIII are characteristic.

Callistomorphus minimus sp. n.
http://zoobank.org/5D16E00A-66CC-441B-AD90- D0BF4399C7A6 Figures 17,26,35,44,53,62,71,80,89,124,129,137,142 Diagnosis. The smallest member of the genus with several characteristic features. Eyes strongly convex, distinctly protruding above margin of head in lateral view. Pronotum distinctly narrowed from base to approximately three-quarters of length, apically sides only slightly expanded towards anterior margin; dorsal surface glabrous, medially only with small, obtuse tubercle. Elytra slender, elongate; without distinct medial tubercles, only with single, small tubercles on intervals. Apical part of elytra and sides of pronotum dark brown, in contrast to colour of the rest parts of body.
Description. Body length (lb) -7.20 mm. Body colour and vestiture (Fig. 17). Body covered almost entirely with yellowish scales. Rostrum brown. Antennae light brown. Lateral part of pronotum dark brown; base of pronotum in dorsal view with two, short, brownish stripes reaching to onefifth of its length; between them small, brown spot. Elytra uniformly yellowish except: brownish apical angles ahead of humerus; base of intervals 3-5; indistinct, suboval darker spot from 1 st to 3 rd intervals before midlength. Apical part of elytra from fourfifth of length dark brown. Scutellum light brown. Mesepimeron, mesanepisternum and mesoventrite brown; metanepisternum together with metaventrite yellowish as most part of elytra. Legs uniformly yellowish.
Head (Figs 62, 71, 80). Slightly wider than long (hw/hl ♀: 1.17). Frons narrower than double width of eye; longitudinal carina between eyes distinct, surface between concave. Eyes strongly convex, circular, slightly longer than half length of head (eyl/ hl ♀: 0.56), distinctly protruding above margin of head in lateral view. Rostrum longer than pronotum (rl/pl ♀: 1.20), 3.40 × as long as maximum width at apex (rl/ arw); longitudinal carina indistinct, polished only from antennal insertion to apex. Scape shorter than rostrum (scl/rl ♀: 0.76). First funicle segment ca 1.2 × as long as 2 nd and 2 × as long as 3 rd ; antennomeres 4 th and 5 th slightly longer than wide; last two as long as wide. Club suboval, 2 × as long as wide, as long as last four funicle segment combined.
Elytra (Figs 26,35). Elongate (el/bew ♀: 1.68). Regularly narrowed from base to apical part; posterior calli weakly developed, not protruding beyond outline of elytral in dorsal view. Surface of striae and intervals not visible due to very dense scales. Medial tubercles absent, on striae only single, small tubercles completely covered with scales. Scutellum slightly longer than wide, slightly protruding above margin of elytra in lateral view.
Etymology. This epithet is the Latin adjective "minimus" (small, little), the new species is the smallest member of the genus.
Remarks. C. minimus sp. n. is a very characteristic species. It is easy to distinguish from other members of the genus by small size, shape of pronotum (not extended apically), reduced tubercles on elytra and pronotum and contrasting coloration of the body.
Description. Body length (lb) -10.80 mm. Body colour and vestiture (Fig. 18). Colour variable, the body dappled with many small spots, from dark brown to yellowish, especially on distal part of elytra and hind legs. In front of medial tubercles on elytra darker spot from suture to base of tubercles. Pronotum with longitudinal yellowish stripes. Striae with distinct, single, short scales in each point of row.
Pronotum (Figs 45, 54). Slightly wider than long (bpw/pl ♂: 1.08). Base 1.35 × as wide as apical margin (bpw/apw); apical margin in dorsal view straight with numerous, distinct tubercles (on SEM photography (Fig. 45) apical margin of pronotum is seen as convex because the image was taken in different angle); in lateral view apical margin straight anteriorly, then converging towards base. Medial tubercle on pronotal disc distinct, strongly protruding, separate apically. Width of medial constriction in relation to apical and basal margin in male: mpw/apw = 0.65, mpw/bpw = 0.45.
Elytra (Figs 27,36). Slightly more than 1.50 × as long as its width (el/bew ♂: 1.55). Subparallel from base to apical part; posterior calli distinct, strongly protruding beyond outline of elytral in dorsal view. Odd intervals with distinct, pointed tubercles that are easily visible in dorsal and lateral views, each furnished with single, hooked, elongate scale. Striae weakly impressed, formed by oval punctures, each with single, whitish scale inside. Medial tubercles distinct, strongly protruding, as high as almost half its length. Scutellum ca 1.20 × as long as wide.
Male terminalia (Figs 98, 112, 119). Penis body distinctly longer than apodemes; almost subparallel from base to apical part; narrowed from fourth-fifth of length, apically widely rounded; basal part unsclerotised; distinctly, regularly curved in lateral view, apically strongly upturned, apex rounded. Internal sac without any structure or sclerites. Parameroid lobes of tegmen with extended common base, as long as apodeme, from half of length divided. Spiculum gastrale basally separate into two extended lobes; hemisternites indistinct. Etymology. This species is dedicated to my colleague Rafał Ruta, PhD (Wrocław, Poland), a great field researcher and specialist in Scirtidae (Coleoptera), who collected some specimens used in this paper, including the holotype of C. minimus sp. n.
Remarks. In lateral view the head and rostrum are similar to those of C. malleus sp. n. (rostrum elongate, slightly curved). However, C. rutai sp. n. has more prominent medial tubercles on the pronotum and elytra, the outline of elytra in dorsal view is more robust, and the shape of the penis is characteristic.
Elytra (Figs 28, 37). Slightly more than 1.50 × as long as its width (el/bew ♀: 1.55); subparallel from base to apical part; posterior calli well developed, protruding beyond outline of elytral in dorsal view; in lateral view strongly convex. Odd intervals with distinct, pointed tubercles furnished with single, hooked, elongate scale; these tubercles are easily visible in dorsal and lateral view. Striae formed by oval punctures, each with single, whitish scale inside. Medial tubercles relatively small, short and weakly elevated. Scutellum slightly longer than wide; surrounded by narrow, asetose area, this in turn surrounded by elongate concentrically oriented scales.
Female terminalia (Figs 125,134,138,143). Abdominal sternite VIII with enlarged apical lobe, as long as half-length of apodeme; medially with wide, distinctly sclerotised area; sides from half of length to apex with distinct punctures, each bearing short, apically hooked setae. Abdominal tergite VIII subtriangular, apically with numerous, elongate setae. Spermatheca as in Fig. 137. Ovipositor with stout gonocoxite, stylus short.
Description. Body length -11.30-12.00 mm. Body colour and vestiture (Fig. 20). Generally dark brown. Indistinct, darker, subtriangular spot between intervals 1-3 situated anteriorly to medial tubercles. White spot on last two intervals present, extended from approximately one-third to two-thirds of length. Apical part of mesepimeron whitish, in contrast to generally dark brown colour of body. Ventral part (metaventrite and ventrites) densely covered by light, variable (from whitish to yellowish) scales.
Elytra (Figs 29,38). Slightly more than 1.50 × as long as its width (el/bew ♂: 1.51; ♀: 1.55). Subparallel from base to apical part; 7 th interval with strongly protruding tubercle before apex of elytra -posterior calli well developed protruding beyond outline of elytral in dorsal view; in lateral view elytra weakly convex. Odd intervals with distinct tubercles, that are pointed on basal half of elytral disc, and more obtuse on apical part. Striae easily visible, formed by distinct oval punctures. Medial tubercles large; slightly longer than one-quarter length of elytra; in lateral view, more or less one-third of elytral height medially. Scutellum short, subquadrate.
Male terminalia (Figs 99,113,120). Penis body longer than apodemes; from base to fourth-fifth of length slightly dilated, remainder of penis distinctly narrowed to rounded apex, its basal part sclerotised; in lateral view strongly curved, apically distinctly upward. Internal sac without any distinct structure or sclerites. Parameroid lobes of tegmen divided almost from base. Spiculum gastrale anchor-shaped; hemisternites well sclerotised, fused with base of spiculum.
Female terminalia (Figs 126, 139 Etymology. This epithet is derived from the Latin adjective "torosus" (muscular) and refers to "muscular" shape and size.
Pronotum (Figs 48, 57). Slightly wider than long (bpw/pl ♂: 1.17). Base 1.24 × as wide as apical margin (bpw/apw); apical margin concave with weakly developed tubercles, only on apical angles tubercles distinct and protruding; in lateral view apical margin protruding towards head; basal margin slightly, but visibly, concave medially; basal angles, in dorsal view, lying clearly below middle part of basal margin. Medial tubercles weakly developed, obtuse; in lateral view slightly protruding above margin of pronotum. Width of medial constriction in relation to apical and basal margin in male: mpw/apw = 0.59; mpw/bpw = 0. 48.
Elytra (Figs 30, 39). Relatively short (el/bew ♂: 1.47); slightly narrowed behind humeral angles; posterior calli developed, protruding beyond outline of elytra in dorsal view. Surface with very rough sculpture; striae composed of subcircular, shallow punctures; surface bordering striae and intervals indistinct, especially on basal half in front of medial tubercles. Apically striae evanescent, only as shallow punctures. Medial tubercles distinct, lower than width at base. Scutellum slightly longer than wide.
Male terminalia (Figs 100, 107, 114 121). Penis body distinctly longer than apodemes; base fully sclerotised; from base slightly dilated, maximum width before midlength; before two-thirds of length distinctly narrowed, then subparallel to widely rounded apex; distinctly curved in lateral view, upward before two-thirds of length. Internal sac without any visible structures or sclerites. Parameroid lobes and tegminal apodeme with similar length; divided beyond middle of length. Spiculum gastrale Y-shaped; hemisternites fused with base of spiculum. Hemisternites of sternite VIII elongate, clavate.
Etymology. This epithet is derived from the Latin adjective "turbidus" (confused, impatient) and refers to my feelings after I wasted too much time trying to create any suitable name for this creature.
Remarks. By the short, distinctly curved rostrum, small size and very characteristic male terminalia (unique form of pygidium, strongly upwardly-directed penis body in lateral view), this species is easy to distinguish within the genus. A female is unknown but may be easily to distinguished based on the description presented above. Callistomorphus   1 Elytra and pronotum glabrous, without prominent tubercles (Figs 26, 35); eyes strongly convex, distinctly protruding above margin of head in lateral view (Fig. 62); length of body less than 7.50 mm............. C. minimus sp. n. -Elytra and pronotum strongly scabrous with distinct medial tubercles and numerous, small tubercles on entire elytra (e.g. Figs 25, 33); eyes more or less convex but not protruding above margin of head in lateral view (e.g. Fig. 58 For a clear presentation of measurements, important for distinguishing particular species, all indices are presented in Table 1. All available specimens have been measured.

Taxonomic position of the genus Callistomorphus Perroud
As was mentioned in the introduction, the genus Callistomorphus was forgotten or ignored for decades in most of the previously published research on Eugnomini.
Currently, the tribe seems to be not monophyletic, without any clear synapomorphies uniting all the genera. Voss (1937) and Marshall (1937) indicated that the essential feature is the elongation and flexibility of the maxillary palpi, but at the same time they emphasised the weakness of this feature for defining Eugnomini, as it does not occur in the genus Pactola. Short maxillary palpi are also present in a close relative of Pactola -Pactolotypus Broun, 1909, as well as in some species of Eugnomus and Rasilinus Mazur, 2016 (Mazur 2016 andMazur -unpublished data). Marshall (1937) distinguished several other features that he suggested as characteristic for Eugnomini, but there are numerous exceptions if we assume the genera currently included in the tribe (Alonso-Zarazaga and Lyal 1999). However, most of these features are represented in Callistomorphus. Cawthra (1966) redefined Eugnominae (sensu Voss 1937) and established a systematic positioning of the tribe, which was subsequently adopted by Alonso-Zarazaga and Lyal (1999) with minor changes. Additionally, Cawthra (1966) included the five genera of Meriphinae Marshall, 1937 in Eugnominae, which are currently treated as a subtribe of Eugnomini (Alonso-Zarazaga and Lyal 1999). The distinguishing characteristics of Eugnomini sensu Cawthra (1966) (without Meriphina), with their relationship to Callistomorphus and the exceptions within the tribe, are presented below.
of Zoology Polish Academy of Sciences (Warsaw, Poland), for her kind assistance in taking the SEM microphotographs, Douglas Willcox for the linguistic corrections and reviewers for all their useful advices.