Metamasius bellorum Anderson

Anderson, Robert S., 2002, The Dryophthoridae of Costa Rica and Panama: Checklist with keys, new synonymy and descriptions of new species of Cactophagus, Mesocordylus, Metamasius and Rhodobaenus (Coleoptera; Curculionoi, Zootaxa 80, pp. 1-94: 53-55

publication ID

http://doi.org/ 10.5281/zenodo.156033

publication LSID

lsid:zoobank.org:pub:6D9F45FE-587D-4161-A54E-DB83C10A112F

persistent identifier

http://treatment.plazi.org/id/01363A23-1449-5B69-FECC-FB9DFE68EC47

treatment provided by

Plazi

scientific name

Metamasius bellorum Anderson
status

new species

Metamasius bellorum Anderson  , new species

( Figs. 53 ­54View FIGURES 51 - 56, 63­ 67View FIGURES 63 ­ 67)

Identification.—The single known specimen of this species, although closely related to M. bromeliadicola  , M. nudiventris  , and M. quadrilineatus  , is quite distinctive based mainly on the male secondary sexual characters of the vestiture of the hind tibiae ( Fig. 65View FIGURES 63 ­ 67) and the extensive and dense vestiture of ventrite 5 ( Fig. 67View FIGURES 63 ­ 67). In M. bellorum  the inner margin of the hind tibia has a tuft of dense elongate hairs at about the midlength, the hairs progressively shorter towards the tibial apex ( Fig. 65View FIGURES 63 ­ 67). In M. bromeliadicola  and M. nudiventris  the hairs along the inner margin of the hind tibia are similarly long but arranged in an row along the tibial length, not as a distinct tuft. On the other hand, in M. quadrilineatus  the hairs are long and arranged as a distinct tuft; however, there are no progressively shorter hairs extended to the tibial apex. As in M. bromeliadicola  , the apex of the pygidium is subtruncate in M. bellorum  ( Fig. 66View FIGURES 63 ­ 67) and much broader than in M. quadrilineatus  or M. nudiventris  . Also, the front coxae in M. bellorum  are widely separated by about one­half the width of a coxa whereas the front coxae in M. bromeliadicola  , M. nudiventris  and M. quadrilineatus  are more narrowly separated by no more than about one­third the width of a coxa. In addition, the apical pilose part of the antennal club is one­third the length of the entire club ( Fig. 64View FIGURES 63 ­ 67).

Description.— Male, length, 11.7 mm; width, 4.9 mm. Female not known. Color mostly black, pronotal disc, dorsal portion of pronotal flanks, and elytra, piceous (elytra variously infuscate); elytra with elongate yellow stripe in interval 4 from near base to apical one­third, and shorter yellow stripe on interval 2 slightly beyond apical one­third.

Rostrum about two­thirds length pronotum; elongate, cylindrical, evenly curved, densely, very finely, shallowly punctate; dorsally at base and laterally at point of antennal insertion with punctures slightly larger, deeper; apical one­half glabrous and virtually impunctate, shining; base of rostrum slightly expanded in dorsal view, basal expanded area short, about one­fifth total rostral length. Rostrum glabrous ventrally; peduncle flat, bilamellate anteriorly. Scrobe with posterior margin separated from anterior margin of eyes by about width of base of scape. Antennal scape about one­half length rostrum; club elongate­oval; apical pilose part one­third length of entire club. Pronotum with lateral margins subparallel to slightly sinuate in basal one­half, convergent subapically, tubulate to apex; moderately densely, deeply punctate on flanks, across apical margin and at middle of base, otherwise disc impunctate; flat at base. Pronotum with length slightly greater than width. Elytra one and one­half times length pronotum; intervals impunctate, flat; striae with distinct, moderately deep, small punctures. Scutellum broadly “V” shaped, length one and one­half times width at base, concave anteriorly, slightly emarginate. Pygidium very slightly convex, not tumescent; coarsely deeply punctate and setose throughout; apex subtruncate; apical margin with row of short setae, also with small patch of denser, erect setae medially near base. Ventrally with front coxae separated by slightly more than one­half width of coxa; prosternum moderately densely, regularly punctate, flat. Lateral portions of meso­, metasternum and ventrites 1 to 5 moderately densely, deeply punctate; punctures larger laterally on metasternum and ventrites 1 and 2; middle of metasternum and ventrites 1­4 virtually impunctate, shining; last ventrite flat, with large round patch of dense long erect hairs covering middle of apical three­quarters. Legs short, sparsely, very shallowly punctate; femora slightly clavate, short, hind femur reaching apex of ventrite 4; inner margins of all tibiae slightly sinuate subapically; hind tibiae with distinct tuft of dense elongate hairs at about the midlength, the hairs getting progressively shorter towards the tibial apex. Tarsi each with third article widely dilated, pilose ventrally except in broad “V” shaped median area; all tarsi with third articles symmetrical; apical margins of third articles moderately deeply emarginate.

Sexual dimorphism.—Although females are not yet known in this species, it can be inferred (based on the related species M. bromeliadicola  , M. nudiventris  and M. quadrilineatus  ) that they will lack the pilosity on ventrite 5 and along the inner margin of the hind tibiae.

Material Examined.—Male HOLOTYPE labelled “ Panama. Chiriqui Prov. / Cont’l Divide Trail / 3­4 ­VII. 1997 / Morris & Wappes” ( CMNC).

Distribution.— Panama (Chiriqui).

Natural history.—No information is available on natural history of this species. The habitat along the Continental Divide Trail near the La Fortuna Dam is a wet ridgetop cloud forest. Given the plant associations of its close relatives M. bromeliadicola  and M. quadrilineatus  , it is suspected that this species also is associated with bromeliads.

Derivation of specific name.—Through their support of the Nature Discovery Fund at the Canadian Museum of Nature, this species is named after the Bell family of Grimsby, Ontario, Canada.