Staminodeus, Nico M. Franz, 2001

Nico M. Franz, 2001, Description And Phylogeny Of Staminodeus, A New Genus Of Derelomini (Coleoptera: Curculionidae) Associated With Cyclanthaceae, The Coleopterists Bulletin 55 (4), pp. 411-432 : 413-419

Staminodeus , new genus

Diagnosis. Like Perelleschus and Systenotelus , Staminodeus keys out to Phyllotrox in Kuschel (1952) . However, Staminodeus ( Fig. 1a ) is distinguished from these taxa and all other presently known Derelomini by the carinate rostrum in both sexes and the frontal spine in females ( Fig. 1b ). With the notable exception of S. inermis Franz , the prothoracic leg in all males is ventrally denticulate.

Male. Small, length 1.2–2.7 mm, width 0.6–1.2 mm, oval to elongate, l/w 1.9–2.5, greatest width near anterior 2/5 of elytron, slightly compressed, dorsally convex, ventrally slightly convex, dark reddish­brown, sculpture punctate, vestiture short, fine, appressed, shiny.

Head. Mandible ( Fig. 2a ). With 2 large dentes, inner dens with triangular emargination, outer dens slightly superposed. Maxilla ( Fig. 2b ). Cardo basally bilobed, apically broadened; stipes apically narrowed, outer margin with 1 large seta; galea lacinia palpiger fused, outer margin with 1 large seta, inner 1/3 setose, inner margin with 4–10 lacinial dentes (sensu Ting 1936); maxillary palps 3­segmented, extending beyond apex of palpiger; I longer than II, transverse; II shorter than III, transverse; III equilateral, apically papillate. Labium ( Fig. 2c ). Prementum with lateral margins apically diverging, apical margin with 2 triangular projections, median tendon triangular, dorsally and ventrally with 2 large setae; labial palps 2­segmented, extending beyond apex of prementum; I II similar in length, equilateral; II apically papillate. Postmentum ventrally with 2 large setae.

Rostrum. In lateral view fairly short, 0.3–0.6 mm, slightly shorter than pronotum, r/p

0.7–1.0, dorsally slightly arcuate, narrowed in apical 1/3, ventrally subrectate; in dorsal view fairly broad, breadth similar throughout; in cross­section subquadrate; dorsally with 2 marginal carinae, extending from frons to subapex of rostrum, slightly diverging, and 2 central carinulae, extending from basal 1/4 to apical 1/3 of rostrum, diverging; glabrate or carinulate in laterobasal 1/3; ventrally with 2 median sulci, extending from base to basal 2/5 of rostrum, subparallel; antennal insertion near apical 1/3; scrobe extending to eye, narrow, deep, subrectate, apically acuminate, shallow, basally vaguely defined.

Antenna. 11­segmented, extending to anterior 1/2 of pronotum, fairly slender; scape extending to eye, slightly shorter than funicle club, slender, slightly arcuate, clavate in apical 1/4; funicle 7­segmented; I large, similar in length to II III, elongate, clavate; II– VII small, similar in length, gradually progressing from elongate to transverse, clavate;

club 3­semented, similar in length to III/IV–VII of funicle, oval, compact; I distinctly longer than II III; II III similar in length; funicle club with short pubescence.

Eye. Fairly large, subcircular, slightly protruded, distant from anterior margin pronotum by 1/4–1/2 diameter of eye, separated by distance greater than breadth of antennal club, black.

Head. Fairly small, globular, transverse, frons glabrate or with 1 spinule.

Thorax. Pronotum. In dorsal view large, globular, l/w 0.8–1.1, greatest width near central region, anteriorly narrowed, slightly to distinctly convex, anterior margin explanate, lateral margins rotundate, posterior margin bisinuate, sculpture densely punctate, vestiture medially converging; in lateral view conical, tumescent above procoxal cavities, narrowed in posterior 1/3, posterior margin lateroventrally explanate.

Epipleura . Mesepisternum triangular; mesepimeron pentagonal, dorsally broadened, projecting to pronotum elytron; metepisternum tetragonal, extending beyond lateral margin of metasternum, anteriorly broadened, posteriorly narrowed; metepimeron extending above posterior 1/4 of metepisternum.

Sterna . Prosternum fairly long, equilateral, convex, procoxal cavities inserted near central region, contiguous; mesosternum nearly 1/2 as long as metasternum, transverse, convex, retracted from ventral plane, mesocoxal cavities inserted at posterior margin, separated by distance nearly 1/5 as broad as mesocoxae; metasternum transverse, laterally convex, centrally plane, medially canaliculate, anterior margin with nodulate projection between mesocoxae, posterior margin with small, triangular projection near inner margin of each metacoxa, metacoxal cavities inserted at posterior margin, separated by distance similar to length of ventrite IV.

Metendosternite. ( Fig. 2d ). Stalk slightly shorter than furcal arms, ventrally broadened, emarginate, separated by median flange; ventral flange broader than stalk, laterally convex; lamina nearly 1/4 as long as central sclerotization; lateral projections apically expanded; anterior tendons inserted near lateral 1/3 of dorsal margin of lamina, slender, converging; furcal arms diverging, dorsally bifurcate.

Legs. Prothoracic leg distinctly longer than mesothoracic leg, slender; procoxa elongate, conical, apically obliquely truncate, inner margin with 1 subapical foveola; protrochanter transverse, apically broadened, oblique; profemur similar in length to pronotum, f/p 0.9–1.3, slender, in cross­section subcircular, ventrally inermous or denticulate; protibia similar in length to profemur, t/f 0.8–1.2, slender, in cross­section subquadrate, width similar throughout, anteroventral margin inermous or denticulate/dentate, apically truncate, posteriorly narrowed, with row of setae ventrally ascending beyond condyle, inermous or mucronate; protarsus 5­segmented, nearly 3/5 as long as protibia; I longer than II, elongate, clavate; II shorter than III, equilateral, clavate; III bilobed, equilateral, lobes slender, diverging; IV nearly 1/4 as long as III, equilateral; V similar in length to II III, elongate, clavate; protarsal claws nearly 2/5 as long as V, paired, simple; I–IV ventrally with long vestiture. Mesothoracic leg slightly shorter than metathoracic leg, fairly slender; mesocoxa equilateral, subcircular; mesofemur fairly slender, slightly sinuate, in cross­section subcircular, slightly compressed, greatest with near apical 2/5, ventrally inermous; mesotibia short, anteroventral margin inermous, apically slightly broadened, inermous or mucronate. Metacoxa transverse, elliptical, medially canaliculate; metatibia fairly long, apically inermous.

Scutellum . Exposed by elytron, intermediate in size, pentagonal.

Elytron. In dorsal view oval to elongate, l/w 1.3–1.6, greatest width near anterior 2/5, broader than posterior margin of pronotum, humeri subquadrate, anterior margin bisinuate, lateral margins subparallel in anterior 1/2, gradually converging in posterior 1/2, posterior margin rotundate, subcontiguous; in lateral view convex, lateral margin slightly sinuate; 10­striate; striae similar in breadth to intervals, punctate, shallow, maculations dark brown, equilateral, subcontiguous; intervals light brown; III VI merging before posterior margin, VII–IX ascending in anterior 1/3, X contiguous with lateral margin; vestiture parallel.

Wing. ( Fig. 2e ). Slightly longer than body, wing/body 1.2–1.5, elliptical to elongate, l/w 2.6–3.7, greatest width near apical 1/3, anterior margin sinuate, posterior margin slightly convex, anal lobe large; C, Sc, R, Cu, Cu1, 2A, and 4A present; with 1 small, triangular maculation in radial field and 2 large, elongate maculations in apical field; radial sclerites and 1 radiomedial sclerotization present; stigmal patch with 2 short macrosetae (see Zherikhin and Gratshev (1995:756); long macrosetae along apical margin of anal lobe; short macrosetae sparse along apical 1/2 of R, dense along posterior margin; microsetae throughout surface.

Abdomen. Venter. Nearly 2 as long as lateral margin of metasternum, laterally convex, centrally plane, posteriorly gradually converging; III IV fused, V–VII separat­ ed; III similar in length to IV, transverse, anterior margin with large, triangular, acuminate projection between metacoxae, anterior edges projected; IV longer than V, transverse; V VI similar in length, transverse; VII similar in length to IV, transverse, posterior margin rotundate, cristulate; vestiture fairly long, semierect. Pygidium. Indistinct (covered by elytron), shorter than VII, transverse, slightly convex, narrow, parallel to orientation of tergum. Tergum VIII. Nearly 1/2 as long as spiculum gastrale, transverse, convex, anterior margin subrectate, anterior edges projected, posterior margin subrectate, plicate, setose. Sternum VIII. Consisting of 2 elongate, plicate, posteriorly diverging sclerites, nearly 1/3–1/2 as long as tergum VIII. Spiculum gastrale. Similar in length to median lobe, narrow, subrectate, medially flanged, basally with irregular expansion, apically bifurcate, with short, slender, perpendicular projections (T­shaped). Tegmen. Nearly 1/3 as long as median lobe, fairly slender, Y­shaped; tegminal apodeme slightly shorter than lateral apodemes, subrectate; lateral apodemes arcuate, projecting to lateral region of median lobe. Aedeagus. Median lobe in dorsal view elongate, l/ w 2.2 –3.5, basal margin irregular, lateral margins subrectate, subparallel, apical margin rotundate; in lateral view fairly broad, slightly sinuate, apically narrowed, slightly deflexed, porose; internally with 2 elongate, laterobasal sclerites, extending from basal region to central region of median lobe; with 1 elongate, median sclerite, extending along laterobasal sclerites; with 2 apical rami; and extended, denticulate regions; aedeagal apodemes short­ er or longer than median lobe, narrow.

Variation. Color variation occurs in all species, i.e., teneral individuals are pale yellow to light­reddish brown. Morphometrical variation occurs to a remarkable extent in male individuals of all species (excepting S. inermis ). Apparently, larger males display positive allometry in the shape of the prothorax, i.e., the pronotum is distinctly expanded, the prothoracic leg is very long, and anteroventral margin of the protibia bears more and larger dentes ( Franz 1999).

Female. Length 1.1–2.4 mm, width 0.6–1.2 mm, l/w 1.8–2.4. Rostrum 0.3–0.7 mm, subequal in length to pronotum, r/p 0.8–1.2; antennal insertion near apical 2/5. Frons with 1 basally triangular, apically acute, arcuate spine, nearly 1/4–3/4 as long as diameter of eye, anteriorly with long, fine, erect setae. Pronotum fairly large, fairly globular, l/w

0.7–1.1, slightly convex. Prothoracic leg longer than mesothoracic leg, fairly slender; procoxa anteriorly with long vestiture; f/p 0.9–1.3, profemur fairly slender, slightly sinuate, in cross­section subcircular, slightly compressed, greatest with near apical 2/5, ventrally inermous; t/f 0.7–1.1, protibia fairly slender, anteroventral margin inermous, apically slightly broadened, inermous; mesotibia apically inermous. Elytron l/w 1.2– 1.6. Wing/body 1.2–1.5, wing l/w 3.0–3.6. Posterior margin of ventrite VII glabrate. Tergum VIII nearly 2/5 as long as sternum VIII, transverse, convex, anterior margin subrectate, posterior margin rotundate, plicate, setose; tergum IX weakly sclerotized, similar in length to sternum VIII, elongate, anteriorly irregular, posteriorly narrowed; sternum VIII narrow, subrectate, medially flanged, apically bifurcate (Y­shaped); coxites nearly 1/2 as long as sternum VIII, elongate, apically setulose, styli elongate, apically with 1 seta; vagina bursa copulatrix large, elongate, longer than sternum VIII, with common oviduct; spermathecal duct apically papillate; spermatheca elongate, abruptly deflexed (C­shaped), basally rugose, apically narrowed; basally with large, elongate gland reservoir.

Variation. Apparently, the frontal spine displays negative allometry ( Franz 1999, in prep.). The morphometrical variation of the prothorax is less remarkable than in males.

Type Species. Staminodeus vectoris , by present designation. Etymology. Named for the association with the staminodes of the inflorescences of Cyclanthaceae (see below). Gender masculine.

Key to the Species of Staminodeus

1. Length 1.1–1.4 mm, light reddish­brown; male with eyes separated by distance similar to breadth of antennal club, frons glabrate, profemur ventrally inermous, anteroventral margin of protibia apically mucronate ( Fig. 3a ); female with eyes separated by distance slightly greater than breadth of antennal club, frontal spine nearly 1/3 as long as diameter of eye, protibia apically mucronate ----------------------------------------- S. inermis n. sp.

1. Length 1.4–2.7 mm, dark reddish­brown; male with eyes separated by distance (slightly) greater than breadth of antennal club, frons glabrate or spinulose, profemur ventrally denticulate/dentate, anteroventral margin of protibia denticulate/dentate, protibia apically inermous or mucronate ( Fig. 3b–g ); female with eyes separated by distance greater than breadth of antennal club, frontal spine nearly 1/2–3/4 as long as diameter of eye, protibia apically inermous -------------------------------------------------------------------- 2

2(1). Male with laterobasal 1/3 of rostrum carinulate, anteroventral margin of protibia with 12–18 denticuli, protibia apically inermous ( Fig. 3b–c ) ----------------------------------------------------------------------------------------------------------------------------------------- 3

2. Male with laterobasal 1/3 of rostrum glabrate, anteroventral margin of protibia with 3–10 dentes, apically mucronate ( Fig. 3d–g ) -------------------- 4

3(2). Male with greatest width near humeri, rostrum slightly broadened in apical 1/3, frons glabrate, procoxal cavities inserted near anterior 1/3 of prosternum, profemur sinuate, posterolaterally denticulate, protibia distinctly arcuate ( Fig. 3b ); female with laterobasal 1/3 of rostrum carinate, frontal spine nearly 1/2 as long as diameter of eye ---------------------------------------- ------------------------------------------------------------------------------------------------------------------------ S. curvitibialis n. sp.

3. Male with greatest width near anterior 2/5 of elytron, breadth of rostrum similar throughout, frons spinulose, procoxal cavities inserted near central region of prosternum, profemur slightly arcuate, posterolaterally glabrate, protibia slightly arcuate ( Fig. 3c ); female with laterobasal 1/3 of rostrum carinulate, frontal spine nearly 2/3–3/4 as long as diameter of eye ----------------------------------------------------------------------------------------- S. denticulatus n. sp.

4(2). Male with frons spinulose ----------------------------------------------------------------------------------- 5

4. Male with frons glabrate -------------------------------------------------------------------------------------- 6

5(4). Male with frontal spine nearly 1/5 as long as diameter of eye, profemur slightly sinuate, ventrally denticulate, protibia subrectate, anteroventral margin of protibia with 6–10 dentes ( Fig. 3d ) -------- S. bispinosus n. sp.

5. Male with frontal spine nearly 2/5 as long as diameter of eye, profemur (distinctly) arcuate, ventrally denticulate/dentate, protibia slightly arcuate, anteroventral margin of protibia with 8–10 dentes ( Fig. 3e ) ---------------- ----------------------------------------------------------------------------------------------------------------------------------- S. forcipis n. sp.

6(4). Male with anteroventral margin of protibia with 3–6 subrectate dentes ( Fig. 3f ) -------------------------------------------------------------------------------------- S. dilatatus n. sp.

6. Male with anteroventral margin of protibia with 6–10 arcuate dentes ( Fig. 3g ) --------------------------------------------------------------------------------------- S. vectoris n. sp.

Figures

Fig. 1. Staminodeus vectoris, a) male, habitus; b) female, frons.

Fig. 2. Staminodeus vectoris, male, a) left mandible, ventral view; b) right maxilla, ventral view; c) labial prementum, ventral view; d) metendosternite, posterior view; e) right wing, dorsal view. Scale bar 0.05 mm for a), b), and c); 0.1 mm for d); and 0.5 mm for e).

Fig. 3. Staminodeus, male, right profemur and protibia, anterior view, a) S. inermis; b) S. curvitibialis; c) S. denticulatus; d) S. bispinosus; e) S. forcipis; f) S. dilatatus; g) S. vectoris. Scale bar 0.1 mm.