Microcryptorhynchus guamae, Zimmerman, 1942

Zimmerman, Elwood C., 1942, Curculionidae of Guam, Insects of Guam I, Honolulu, Hawaii: Bernice P. Bishop Museum, pp. 73-146 : 115-116

25. Microcryptorhynchus guamae , new species (pl. 3, E).

Derm shiny black when exposed, with antennae and tarsi reddish, covered with a comparatively thin incrustation that gives the derm a dull appearance before abrasion; setae mostly conspicuously white, but usually with some dusky setae.

Head narrowly exposed from above, densely punctate, surface appearing asperate when denuded, with numerous broad, squamiform setae on crown and one or two rows of larger, erect, squamiform setae along either side of front extending from rostrum, inner rows usually incomplete or absent, but row adjacent to inner margins of eyes always well developed. Rostrum with four rows of broad squamiform setae and encrusted from base to insertion of antennae, distinctly punctate beyond antennae, three dorsal carinae, except part of median one, usually obscured or concealed in male, female with setae and incrustation at base only, otherwise bare and with broad median carina, which becomes evenly broader from base to antennae, and narrower lateral carina well defined and conspicuous, sulci between them distinct. Prothora.i- almost one third broader than long (3:2.25), strongly rounded on sides from base to subapical constriction at apical fourth, constriction continued distinctly across dorsum; base subtruncate, basal squamose, declivitous area quite simple, very coarsely, densely reticulately punctate, rather closely set with large, erect, usually broad spatulate setae throughout. Elytra quite strongly inflated and subglobose, but slightly longer than broad (2.5:2.25), two and one half times longer than prothorax, evenly and strongly rounded on sides, without a subapical constriction, longitudinal dorsal contour strongly convex and rising far above summit of pronotum, and strongly discontinuous with dorsal contour of prothorax; striae coarse, as broad or broader than intervals, punctures very large, coarse and quadrate·; intervals convex, each bearing a row of very conspicuous, long, erect, heavy, spatulate or clavate setae. Legs with femora and tibiae with rows of long, erect or slanting, spatulate setae and at least tibiae with more or less matted, dense hair; tibial uncus arising from outer apical angle and strongly developed throughout. Sternum with mesosternal receptacle deep and cavernous, pectoral canal terminating at or in front of middle of mesocoxae in male, but only slightly before metasternum in female, hind wall of receptacle about twice as broad in male as female, usually only slightly protuberant; metasternum very coarsely and closely punctate, setose, one half to three fourths as long between mid and hind coxae as breadth of a mesocoxa, metacoxae separated by a distance twice that of length of metasternum along median line. Venter with first two ventrites coarsely, densely, reticulately punctured, setose, strongly tumid and quite similar in both sexes, intercoxal process arcuate; ventrite 5 coarsely reticulate, indistinctly punctate, bearing scattered setae. Length, 1.5-1.8 mm.; breadth, 0.8-1.25 mm.

Holotype male, allotype female and 16 paratypes collected at Ritidian Point, June 2, 1936, Usinger ; one from same place, April 15, Bryan ; one, Piti , from Cestruni diurnum (palliduni on label), May 2, Usinger ; four taken by Usinger and one by Bryan , Upi Trail, May 5; one, Piti (in house), May 13, Swezey ; two, Machanao (on unknown tree), June 4, Swezey ; one, Machanao , June 30; one at Atantano (from rice seedling plot), Sept. 3, one at Merizo , Oct. 2, Swezey ; one without specific locality and among the National Museum material, three from the same lot, FuIIaway ; four, from Premna gaudichaudii , July 23, 1937, Oakley , no. 37-24080.

This species is closely aIIied to M. premnae but it lacks the median pronotal carina found on M. premnae . This and M. premnae belong to that group of rotund species exemplified by M. glomus MarshaII from Samoa and M. vagus Zimmerman from the Society Islands, but they have setae on aII of the elytral intervals instead of on the alternate intervals only.