Cactophagus riesenorum 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; Curculionoidea), Zootaxa 80, pp. 1-94 : 38-41

Cactophagus riesenorum Anderson , new species

( Figs. 33­34 , 39­41 )

Identification.—The only known specimen of C. riesenorum can be easily recognized by the pattern of elytral coloration (single transverse basal red band) ( Figs. 33­34 ), tumescent front of metasternum, slightly sinuate basal margin of pronotum ( Fig. 33 ) and apically carinate pygidium. This species is most similar in color pattern to C. aurofasciatus but that species is much broader in dorsal aspect, has a distinctly sinuate basal pronotal margin, has a virtually impunctate, short rostrum, has a straight upper edge of the antennal scrobe, and has a wider basal red band on the elytra. In rostral form, the species resembles C. duplocinctus but that species has a distinctly sinuate basal pronotal margin and an anteriorly medially excised scutellum. Other characters distinguish C. riesenorum from all members of Cactophagus with an anteriorly tumescent metasternum ( C. aurofasciatus group of Vaurie [1967]).

Description. Male, length, 14.6 mm; width 5.1 mm. Female not known. Color black, with elytra with distinct transverse basal red band in apical one-quarter.

Rostrum slightly longer than pronotum; elongate, cylindrical, evenly curved, densely, shallowly punctate dorsally and laterally in basal one-third; apical two-thirds glabrous and virtually impunctate, shining; base of rostrum slightly expanded in dorsal view, basal expanded area short, about one-fifth total rostral length; in dorsal view with shallow median sulcus in basal expanded; in lateral view with deep impressed semi-circular area behind point of antennal insertion. Peduncle slightly convex, bilamellate. Scrobe with posterior margin about two times width of base of scape from anterior margin of eyes. Antenna with scape moderately long, about one-half length rostrum; club elongate-oval; apical pilose part subequal in length to basal glabrous part. Pronotum with lateral margins subparallel to slightly convergent in basal one­half, more markedly convergent at apical one­third, subapically constricted, tubulate to apex; moderately densely, moderately deeply, regularly punctate on disc and flanks; disc moderately deeply impressed subbasally at middle; hind margin of pronotum very slightly sinuate at middle. Elytra one and one­third times length of pronotum; intervals very finely, shallowly punctate, convex; striae deeply impressed, sparsely punctate; bases on intervals 2­5 not produced anteriorly. Scutellum small, “V” shaped, length slightly greater than width at base, concave. Pygidium deeply regularly punctate throughout; apex broadly acuminate; with distinct, apical median finely setose carina. Ventrally with front coxae separated by width of scape; prosternum moderately densely, irregularly punctate, flat but sloping anteriorly. Metasternum impunctate medially, with large irregular punctures laterally; anterior process of metasternum markedly prominent and tumescent at middle; venter otherwise with moderately deep, sparse punctures laterally on ventrites 1­5, on mesepisternum, mesepimeron, less so on metepisternum; last ventrite flat, deflexed ventrally at apex, apex narrowly impressed at middle. Legs moderate in length, moderately densely, shallowly punctate; femora clavate, hind femur longer, almost reaching middle of ventrite 5; front coxae with inner faces rounded; inner margins of tibiae straight, with row of short, peglike setae. Tarsi each with third article widely dilated, pilose ventrally except in narrow median line at base; all tarsi with third articles symmetrical and apical margins truncate.

Material examined.—Male HOLOTYPE labelled "S. Irazuzta 2/16 / CR, Puntarenas Prov. / Monteverde 14­1800m / 10°18'N, 84°48'W / 1986" (CMNC). Distribution.— Costa Rica (Puntarenas).

Natural history.—There is no information available on natural history.

Derivation of specific name.­ Through their support of the Nature Discovery Fund at the Canadian Museum of Nature, this species is named after the Riesen family of Calgary, Alberta, Canada.

Comments.—The holotype was discovered in the student collections of the Estacion Biologica Monteverde in June 2001.

Figures

FIGURES 33 - 38. Cactophagus species. 33 - 34. Cactophagus riesenorum Anderson. 33. Dorsal habitus. 34. Lateral habitus. 35 - 36. Cactophagus silron Anderson. 35. Dorsal habitus. 36. Lateral habitus. 37 - 38. Cactophagus sunatoriorum Anderson. 37. Dorsal habitus. 38. Lateral habitus.

FIGURES 39 ­ 41. Cactophagus riesenorum Anderson. 39. Lateral view of head, male. 40. Antenna. 41. Hind leg, male.