Dryophthoridae of Costa Rica and Panama

Metamasius Horn, 1873

Diagnosis: Small to large, 7-25 mm in total body length; elongate-oval in form, uniformly black or black with red, orange or yellow markings; antennal funicle of 6 articles, scape cylindrical, apex extended to posterior margin of eye or beyond; rostrum cylindrical, curved ventrally or straight; anterior margin of pronotum straight behind eye; tarsus of 5 articles, but article 4 small, located at very base of article 3, article 3 wider than 2 and bilobed ventrally, ventral pilosity various, forming pads which cover one-third or more of ventral surface, article 5 (claw-bearing article) with apical venter smooth; legs of male and female generally different in shape and vestiture, those of male with vestiture in the form of rows or tufts of longer hair or of a different shape; front coxae separated, lacking tubercle between front coxae, metasternum more or less flat between mesocoxae; pygydium exposed beyond elytra; scutellum triangular, widest at or near base; male with aedeagus with complete or incomplete lateral line.

Taxonomic notes: The complete or incomplete lateral line on the male aedeagus is unequivocal in distinguishing Metamasius from Rhodobaenus and Cactophagus. If males are not dissected, separation of Metamasius from some Cactophagus and some of the larger black Rhodobaenus can be difficult.

Natural history: Where known, species of Metamasius are associately mostly with palms (Arecaceae) and bromeliads, including pineapple (Bromeliadaceae). Metamasius distortus is associated with Ceiba (Bombacaceae) and the fruits of Sterculia (Sterculiaceae). Two species may prove associated with Cyclanthaceae. While preliminary, based on the meager biological information available, species of Cactophagus may be restricted to Araceae and Orchidaceae. In contrast, species of Metamasius may prove restricted to Arecaceae and Bromeliadaceae.

Diversity: About 60 species of Metamasius are known from Central and South America; 30 are known from Costa Rica and 29 from Panama, with 24 shared between the two countries.

	Key to species of Metamasius in Costa Rica and Panama

1	Outer apex of middle and hind tibia with distinct, minute tooth	2
	- Outer apex of middle and hind tibia rounded or obtusely angulate, not dentate	3

2	Venter, except for abdominal ventrites, virtually impunctate; male rostrum with inner margin crenulate; inner margin of hind tibia of male with subapical tuft of long curled hairs	M. cincinnatus Champion (in part)
	- Venter distinctly punctate; male rostrum with inner margin smooth; hind tibia of male lacking hairs	M. rugipectus (Champion)

3	Elytral sutural interval and intervals 3, 5 and 7 elevated and wider than other intervals (fourth interval may be elevated at midlength); pronotum foveate on each side in front of base, also with lateral margins (viewed dorsally) somewhat emarginate from base to just beyond midlength	M. distortus (Gemminger and Harold)
	- Elytral intervals all of equal elevation and width; pronotum not foveate on each side in front of base, lateral margins (viewed dorsally) not emarginate	4

4	Pygidium from base to apex with high, bluntly keeled, tomentose swelling, in lateral view with apex distinctly truncate and angulate; inner margin of middle tibia of male sinuate and slightly expanded	M. pygidialis Guenther
	- Pygidium flat to slightly convex, midline may be setose and slightly elevated but not markedly so; in lateral view with apex rounded; inner margin of middle tibia of male straight to slightly sinuate, not expanded sinuate	5

5	Antennal club with apical pilose portion very short, visible in lateral view only at extreme apex of club as a narrow line; rostrum more or less straight, male with ventral margin irregularly crenulate	M. wolfensohni Anderson
	- Antennal club with apical pilose portion one-quarter or more length of entire club; rostrum straight or curved ventrally to various extent, male with ventral margin irregularly crenulate or smooth	6

6	Hind tarsal article 3 only slightly expanded, width at apex less than twice width of article 2 at apex	7
	- Hind tarsal article 3 markedly expanded, width at apex more than twice width of article 2 at apex	8

7	Antenna with apical pilose portion one-third length of entire club; rostrum with fine, yellow pilosity throughout most of length, divided dorsally by median glabrous line; tarsi densely tomentose dorsally	M. cerasinus Vaurie
	- Antenna with apical pilose portion about one-half length of entire club; rostrum with fine, yellow pilosity in basal one-third only; tarsi sparsely tomentose dorsally	M. hebetatus (Gyllenhal)

8	Prosternum in front of coxae with ring of distinct yellow hairs (usually as long as apical article of antennal funicle); antenna with apical pilose portion of club distinctly truncate and quadrate at apex	M. hemipterus (Linnaeus)
	- Prosternum in front of coxae glabrous or very finely pilose; antenna with apical pilose portion of club broadly rounded	9

9	Prosternum in front of coxa with abrupt, tumid and punctate transverse swelling (swelling less pronounced on females and small males); male with large (huge in some specimens) ventrally produced, apically rounded tooth on the peduncle of postmentum; base of elytral interval 6 excavate and bidentate	M. maculiventris Champion
	- Prosternum flat to slightly convex in front of coxa; male with at most a small ventrally produced, rounded tooth on peduncle of postmentum; base of elytral interval 6 not modified	10

10	Elytra with basal one-half of all intervals filled with large, irregular, deep punctures; pronotum with similar, large deep punctures; male rostrum with ventral margin crenulate	M. submaculatus Champion
	- Elytra with all intervals impunctate or at most very finely punctate; pronotum with punctures various; male rostrum with ventral margin crenulate or smooth	11

11	Elytral striae each with numerous paired, large, micropilose pits	M. leopardinus Anderson
	- Elytral striae impunctate or with at most small linearly arranged fine punctures	12

12	Pronotal disc virtually impunctate (except for apical collar and extreme basal margin)	13
	- Pronotal disc distinctly finely to coarsely punctate, punctures may be limited to subbasal median impressed area or may be fine and shallow throughout	19

13	Rostrum short and almost straight, length approximately 3-4 times width at apex; antennal club with apical pilose portion short, about one-quarter length of entire club	M. burcheri Anderson
	- Rostrum slightly to moderately curved, length greater than 5 times width at apex; antennal club with apical pilose portion at least one-third or more length of entire club	14

14	Pronotum with flanks and prosternum virtually impunctate; inner margin of hind tibia of male with tuft of dense, long golden hairs at middle	M. cincinnatus Champion, (in part)
	- Pronotum with flanks and prosternum distinctly punctate; inner margin of hind tibia of male with or without tuft of long golden hairs	15

15	Rostrum with large, distinct punctures immediately in front of point of antennal insertion; pronotal disc orange or red, with elongate black stripe along midline and shorter subbasal black spots on either side of midline	M. quadrilineatus Champion
	- Rostrum with at most fine, shallow, indistinct punctures immediately in front of point of antennal insertion; pronotal disc black, red with small black paramedian spots just anterior to midlength, or red with very broad black median area extended across basal margin	16

16	Pronotum red with small black paramedian spots just anterior to midlength, or red with very broad black median area extended across basal margin; male rostrum with ventral margin crenulate; male hind tibia with ventral margin with row or long, golden hairs in apical three-quarters	M. dimidiatipennis (Jekel)
	- Pronotum entirely black; male rostrum with ventral margin smooth; male hind tibia with ventral margin with row of uniformly short golden or brown peg-like hairs	17

17	Body robust, length less than twice maximum width; metasternum tumid in lateral view; pronotum with basal margin virtually impunctate; elytra with series of small yellow dots near middle or a broad yellow band at middle with small black spot on interval 3	M. sellatus Champion
	- Body more slender, length more than twice maximum width; metasternum flat medially; pronotum with basal margin with row of punctures; elytra with transverse yellow or orange band just anterior to, or posterior to, midlength	18

18	Elytra with transverse yellow or orange band just posterior to midlength; male abdomen with last ventrite impressed; male hind tibia with inner margin with tuft of long golden brown hairs	M. fasciatus (Olivier)
	- Elytra with transverse yellow or orange band just anterior to midlength; male abdomen with last ventrite flat; male hind tibia with inner margin with row of uniformly short brown hairs	M. callizona (Chevrolat)

19	Pronotum with disc with distinct transverse subbasal impression or crease; Pronotum orange-red with single median black stripe of more or less same width throughout length; elytra with black "V-shaped" sutural maculation at middle (other various black markings also present); body size small, 6.0-6.9 mm	M. vaurieae Anderson
	- Pronotal disc flat with slight to deep longitudinal or round subbasal impression; pronotum with color pattern various; elytra with color pattern various; body size small to large, 6.5-23.5 mm, most 8.0-12.0 mm	20

20	Pronotal disc with punctures confined to subbasal median area (and subapically along apical collar)	21
	- Pronotum with disc with punctures (although fine and shallow in some specimens) more or less evenly scattered throughout	25

21	Pronotum with distinct subbasal median impression with large, deep punctures	22
	- Pronotum with subbasal median area flat or very slightly impressed, punctures moderate to small and fine	23

22	Abdomen with last ventrite with large patch of long, dense, golden brown hairs in apical one-half; all tibiae of male with inner margins with dense, long, golden brown hairs; body size large, 21.0-23.5 mm	M. sierrakowskyi (Gyllenhal)
	- Abdomen with last ventrite glabrous (female) or with two small paramedian patches of long golden hairs at about midlength (male); front and middle tibiae of male with inner margins with sparse, elongate golden hairs, hind tibia with inner margin with tuft of long golden hairs at about midlength; body size moderate, 9.5-13.0 mm	M. difficilis Guenther

23	Rostrum in lateral view more or less of same width throughout length; antennal club about as wide as long; male rostrum with distinct, paired, ventral swellings under apical margin of scrobe	M. shchepaneki Anderson
	- Rostrum in lateral view more distinctly tapered in apical one-half; antennal club much longer than wide; male rostrum with ventral margin smooth	24

24	Front coxae separated by about one-half the width of a coxa; male (female not known) hind tibia with inner margin with distinct tuft of dense, long, golden hairs at midlength	M. bellorum Anderson
	- Front coxae separated by no more than about one-third the width of a coxa; male hind tibia with inner margin with row of sparse, long, golden hairs in apical two-thirds	M. bromeliadicola Champion

25	Rostrum of male (female not known) ventrally near base with tuft of dense, coarse, yellow hairs; antennal club with apical pilose portion about one-quarter length of entire club	M. crinitus Vaurie
	- Rostrum glabrous ventrally; antennal club with apical pilose portion about one-third or more length of entire club	26

26	Pronotal disc with punctures large, dense and deep, many contiguous or nearly so; rostrum of male with ventral margin crenulate; pygidium with pair of paramedian apical tufts of long golden hairs	M. octonotatus Champion
	- Pronotal disc with punctures fine, sparse and shallow to moderately dense and moderately deep, punctures widely separated, not contiguous or nearly so; rostrum of male with ventral margin smooth or with slight ventral swelling at about midlength; pygidium various	27

27	Pronotum widest at base, tapered uniformly throughout length to apex, elongate-narrow in general form; male hind tibia with inner margin with row of dense, long, dark hairs in apical two-thirds	M. alveolus Vaurie
	- Pronotum widest anterior to base or of more or less equal width from base to near apex, abruptly constricted and tapered subapically, subquadrate in general form; male hind tibia with inner margin with row of uniformly short hairs or with row of sparse, long, fine yellow hairs in apical two-thirds	28

28	Rostrum in lateral view robust in form, length about 4 to 5 times width at apex, about as wide at apex as at base, or at most only very slightly narrower at apex	29
	- Rostrum in lateral view elongate and slender in form, length much more than 5 times width at apex, distinctly narrower at apex than at base	31

29	Inner margin of front tibia with rows of dense, long golden hairs; rostrum with ventral margin crenulate	M. dasyurus Champion, male (in part)
	- Inner margin of front tibia with row of uniformly short hairs; rostrum with ventral margin smooth	30

30	Elytral interval 5 with pair of tumid elongate orange/red spots or a longer continuous tumid line, spots or lines slightly distorting adjacent elytral striae; male abdomen with last ventrite (5) with large patch of golden hairs in apical two-thirds; female abdominal ventrites 3-5 with elongate, fine, appressed, golden hairs along midline	M. hooveri Anderson
	- Elytral interval 5 various in color, not tumid, adjacent elytral striae not distorted, straight; male abdomen with last ventrite (5) with large patch of golden hairs in apical two-thirds; female abdominal ventrites 3-5 glabrous	M. sulcirostris Champion

31	Rostrum more or less straight, anteriorly directed; body size small, 6.0 mm	M. scutiger Champion
	- Rostrum at least somewhat curved ventrally; body size, small to moderate, 7.5-14.3 mm	32

32	Elytra with only transverse orange or red band at basal one-third; body size small, 7.5-9.3 mm	M. murdiei Anderson
	- Elytra with pattern various, if band present, it is at midlength and other parts of elytra with at least some red or orange as well; body size small to moderate, 8.2-14.3 mm	33

33	Pronotum and elytra flat in lateral view; pronotum uniformly distinctly punctate over entire surface of disc; elytral intervals with distinct fine punctures; pygidium of female with midline with patch of dense, elongate hairs in apical one-half, no apical tufts present	M. atwoodi Anderson
	- Pronotum and elytra at least slightly convex in lateral view; pronotum with punctures various in depth and density over disc; elytral intervals with fine punctures or impunctate; pygidium of female with pair of small paramedian apical tufts of hair or with large subapical tuft as well as pair of paramedian apical tufts	34

34	Elytra with slightly oblique red band at midlength and with intervals 3-6 red in area of subapical callus; ventral margin of rostrum of male with slight ventral swelling at about midlength; pygidium with pair of paramedian apical tufts; male hind tibia with inner margin with row of minute, peg-like brown spines	M. richdeboeri Anderson
	- Elytra with pattern various; ventral margin of rostrum of male either smooth or crenulate; pygidium various; hind tibia with inner margin various	35

35	Tarsi with venter of article 3 with midline glabrous in a broad, triangular patch towards base; pronotum with subbasal area with larger and deeper punctures than elsewhere on disc; areas lateral to punctate area virtually impunctate; male abdomen with last ventrite and inner margin of hind tibia with elongate, fine hairs	M. nudiventris Champion
	- Tarsi with venter of article 3 completely pilose, no glabrous spots evident; pronotum with subbasal area with punctures of more or less the same size and depth as elsewhere on disc, if punctures deeper and denser in impressed subbasal area, areas lateral to punctate area with at least some punctures; male abdomen with last ventrite glabrous and with inner margin of hind tibia with uniformly minute, peg-like brown spines	36

36	Pygidium with single, broad apical patch of short hairs; male front tibia with inner margin with row of uniformly short, peg-like brown spines; male rostrum with ventral margin smooth	M. gallettae Anderson
	- Pygidium with large, preapical tuft of long hairs and small paramedian apical tufts (tufts may be contiguous medially); male front tibia with inner margin with rows of dense, long, fine golden hairs; male rostrum with ventral margin crenulate	M. dasyurus Champion, (in part)

Metamasius alveolus Vaurie

Distribution: Costa Rica and Panama.

Natural history: Adults have been collected in leaves of bromeliads.

Metamasius atwoodi Anderson

Distribution: Costa Rica (Isla del Coco).

Natural history: Specimens were collected near sea level, likely on or near the coast. A single specimen has a fibrous pupal cell mounted along with the adult. This suggests this specimen was collected in the pupal cell or had recently emerged from it. The source plant of this fibrous material is unknown to me but one additional specimen was collected from a Rooseveltia (=Euterpe Mart.) palm tree fall and this might be the plant in question.

Metamasius bellorum Anderson

Distribution: Panama.

Natural history: The holotype was collected in a wet ridgetop cloud forest along the Continental Divide Trail at 1300m near the La Fortuna Dam in Chiriqu province. Given the plant associations of its close relatives M. bromeliadicola and M. quadrilineatus, it is suspected that this species also is associated with bromeliads.

Metamasius bromeliadicola Champion

Distribution: Costa Rica.

Natural history: Vaurie (1967a) notes that specimens have been collected in bromeliads.

Metamasius burcheri Anderson

Distribution: Costa Rica.

Natural history: This species is closely related to species associated with bromeliads and likely is similarly associated. The two known specimens were collected in forest at 1250m in Cartago Province and 800m in Guanacaste Province.

Metamasius callizona Chevrolat

Distribution: Guatemala, Mexico and Panama.

Natural history: Vaurie (1967a) reports this species is associated with bromeliads including pineapples.

More information on natural history is available at http://creatures.ifas.ufl.edu/orn/m_callizona.htm
http://bromeliadbiota.ifas.ufl.edu/wvbrom.htm

Metamasius cerasinus Vaurie

Distribution: Panama; also in South America.

Natural history: No significant information.

Metamasius cincinnatus Champion

Distribution: Costa Rica, Nicaragua and Panama; also in South America.

Natural history: Vaurie (1967a) reports this species is associated with bromeliads. Frank and Thomas (2002) report it from Panama on Vriesia werckleana (Bromeliadaceae).

Metamasius crinitus Vaurie

Distribution: Costa Rica and Panama.

Natural history: No significant information.

Metamasius dasyurus Champion

Distribution: Costa Rica, Honduras and Panama; also in South America.

Natural history: Vaurie (1967a) reports this species has been collected on the fermenting sap of palms and on cuttings and sheaths of fallen palms of the genera Iriartea and Euterpe (Arecaceae). This is a very commonly collected species.

Metamasius difficilis Guenther

Distribution: Costa Rica, Honduras and Panama; also in South America.

Natural history: Vaurie (1967a) records an incidental record of a specimen associated with bananas.

Metamasius dimidiatipennis (Jekel)

Distribution: Costa Rica, Guatemala, Mexico, Nicaragua and Panama; also in South America.

Natural history: Vaurie (1967a) reports this species is associated with bromeliads incluing pineapples. Females oviposit on the stems of pineapple plants and the larvae tunnel in the stems, eventually killing the plant.

Metamasius distortus (Gemminger and Harold)

Distribution: Costa Rica, Nicaragua and Panama; also in South America.

Natural history: Vaurie (1967a) reports that specimens from Brazil have been associated with branches of Ceiba (Bombacaceae) and the fruits of Sterculia (Sterculiaceae). She also notes a single specimen from Costa Rica collected on the leaves of Asterogyne (Arecaceae). Vanin (1998) notes two specimens taken on a fruit of Clusia grandiflora Splitg. (Clusiaceae) in Belem, Brazil, and another specimens collected on Bactris acanthocarpa (Mart.) (Arecaceae) near Manaus. Vanin himself collected a long series of adults from the rotten stipes of Euterpes edulis (Areceaeae) in Salesopolis, Sao Paulo. No larvae were found but some adults were still in pupal chambers made from the fibrous material of the host palm. It looks like this species breeds in a variety of palm species throughout its wide range. This is a very commonly collected species.

Metamasius fasciatus (Olivier)

Distribution: Costa Rica and Panama; also in South America.

Natural history: Vaurie (1967a) reports this species is associated with bromeliads. An adult has been collected from the bromeliad Pitcairnia arcuata (André) André.

Metamasius gallettae Anderson

Distribution: Panama; also in South America.

Natural history: Specimens were collected in montane cloud forest and montane evergreen forest transition between 1200-1450m in the Darien province.

Metamasius hebetatus (Gyllenhal)

Distribution: Costa Rica, Nicaragua and Panama; also in South America.

Natural history: Vaurie (1967a) notes that this species has been collected on bromeliads, with bananas, and with palms. Adults and larvae were collected on fallen Iriartea (Arecaceae) leaves.

Metamasius hemipterus (Linnaeus)

Distribution: Belize, Costa Rica, El Salvador, Guatemala, Honduras, Mexico, Nicaragua, Panama and United States; also in West Indies and South America.

Natural history: This species is called the West Indian sugarcane borer or Silky Cane Weevil. Vaurie (1967a) reports that it is associated with stems of sugarcane and banana and also with various palms. Larvae appear to develop in overripe, rotting, broken or sick plants but will proceed from damaged tissues into healthy parts of the plant. The biology on sugarcane is summarized by Wolcott (1955). The species is readily transported in banana plants and has been widely introduced into areas where bananas are grown.

More information on natural history is available at http://creatures.ifas.ufl.edu/orn/silky_cane_weevil.HTM

Metamasius hooveri Anderson

Distribution: Costa Rica.

Natural history: All specimens have been collected in lowland rainforest.

Metamasius leopardinus Anderson

Distribution: Costa Rica and Panama.

Natural history: Specimens have been collected from 1050-1700 m elevation. One specimen was collected from a bromeliad.

Metamasius maculiventris Champion

Distribution: Costa Rica, Nicaragua and Panama; also in South America.

Natural history: Vaurie (1967a) reports a specimen collected on fermenting palm sap.

Metamasius murdiei Anderson

Distribution: Costa Rica.

Natural history: No significant information.

Metamasius nudiventris Champion

Distribution: Costa Rica, Mexico, Nicaragua and Panama.

Natural history: Vaurie (1967a) reports this species is associated with bromeliads. Frank and Thomas (2002) report it from Tillandsia bulbosa in Belize.

Metamasius octonotatus Champion

Distribution: Costa Rica and Panama; also in South America.

Natural history: Adults have been reared from Chamaeodorea tepejilote (Arecaceae).

Metamasius pygidialis Guenther

Distribution: Costa Rica and Panama; also in South America.

Natural history: Vaurie (1967a) reports this species is associated with palms. Adults have been collected on the fallen leaves and leaf sheaths of Euterpe and Socratea exorrhiza (Arecaceae).

Metamasius quadrilineatus Champion

Distribution: El Salvador, Guatemala, Honduras, Mexico and Panama.

Natural history: Vaurie (1967a) reports that this species is associated with bromeliads. Frank and Thomas (2002) report it from Tillandsia guatemalensis, Tillandsia sp., Vriesia chiapensis, and Billbergia sp.

Metamasius quadrisignatus (Gyllenhal)

Distribution: Panama (questionable); also in West Indies.

Natural history: Vaurie (1967a) reports this species is associated with bromeliads.

Metamasius richdeboeri Anderson

Distribution: Costa Rica and Panama.

Natural history: All specimens have been collected in lowland rainforest. Some specimens collected in the Osa Penninsula have fibrous pupal cells mounted along with the adult beetles. This suggests these specimens were collected in the pupal cells or had recently emerged from them. One series of such specimens from Cerro Rincon (775 m) was collected in the roots of “chonta” (Socratea exorrhiza; Arecaceae) along with larvae. It is possible that the other Osa specimens were from the same species of palm.

Metamasius rugipectus (Champion)

Distribution: Costa Rica, Mexico and Panama.

Natural history: Vaurie (1967a) reports this species is associated with bromeliads. Frank and Thomas (2002) report it from Catopsis (either C. hahnii or C. morreniana) in Honduras and from Tillandsia guatemalensis in Guatemala.

Metamasius scutiger Champion

Distribution: Costa Rica and Panama.

Natural history: No significant information.

Metamasius sellatus Champion

Distribution: Belize, Costa Rica, Guatemala, Mexico, Nicaragua and Panama.

Natural history: Vaurie (1967a) reports a single record from a bromeliad. An adult also has been collected from the bromeliad Pitcairnia arcuata (André) André. Frank and Thomas (2002) record it from Tillandsia guatemalensis in Mexico and Tillandsia bulbosa in Belize.

Metamasius shchepaneki Anderson

Distribution: Costa Rica and Panama.

Natural history: All specimens have been collected in montane evergreen forest or cloud forest at elevations from 820-1250m. The allotype is labelled as collected on a vine, Carludovica sp., but this most likely refers to a species of Asplundia (both genera are Cyclanthaceae) as no species of the former climb.

Metamasius sierrakowskyi (Gyllenhal)

Distribution: Costa Rica, Nicaragua and Panama; also in South America.

Natural history: Vaurie (1967a) reports that an adult was collected on the leaf of a “fan palm” (Cyclanthaceae?). An additional adult has been collected in Costa Rica on flowers of Cyclanthaceae.

Metamasius submaculatus Champion

Distribution: Costa Rica, Nicaragua and Panama; also in South America.

Natural history: Vaurie (1967a) reports this species is associated with bananas and banana-like plants, such as Heliconia. Other adult specimens have been collected on Heliconia.

Metamasius sulcirostris Champion

Distribution: Costa Rica, Guatemala, Nicaragua and Panama.

Natural history: No significant information.

Metamasius vaurieae Anderson

Distribution: Costa Rica.

Natural history: Specimens were collected from 1500-1800m elevation in cloud forest in the vicinity of Monteverde and Santa Elena in Puntarenas province. Three specimens were collected by beating the roots and stems of epiphytic Araceae. The holotype was collected on a ‘palm leaf’ but this is likely incidental.

Metamasius wolfensohni Anderson

Distribution: Costa Rica and Panama; also in South America.

Natural history: Specimens have been collected from 700-1350m elevation in montane evergreen forest in Costa Rica, and near 200m in lowland rainforest in Panama and Ecuador.