Chaetometra robusta ( Hungerford, 1939 )

Polhemus, Dan A., 2022, Two new genera and six new species of Terrestrial Hydrometridae (Hemiptera: Heteroptera) from French Polynesia, Zootaxa 5190 (1), pp. 69-98 : 93-95

Chaetometra robusta ( Hungerford, 1939)

Figs. 5–8 , 35–38

Trichometra robusta Hungerford, 1939: 218 .

Chaetometra robusta: Hungerford, 1950: 73 .

Discussion. Hungerford (1939) originally described this species in the genus Trichometra , which proved to be a primary homonym of Trichometra Clark, 1908 in the Crinoidea, necessitating the replacement name Chaetometra ( Hungerford, 1950) .

Chaetometra robusta may be easily recognized within Hydrometridae as a whole by its rather short head and highly setiferous body and appendages. Photographs of the holotype, held in the Bishop Museum, are provided here to aid in future recognition of this unusual species ( Figs. 35–37 ).

Ecological notes. The species is known from a single specimen taken in 1932 on Mt. Temetiu, the highest summit on the island of Hiva Oa in the Marquesas, and additional surveys there by a team of entomologists in October 1999 and again in August 2001, the latter operating for several days out of a research camp established on the upper mountain ( Figs. 5–8 ), failed to locate additional specimens. Instead, these surveys collected examples of the new genus and species Marquesametra hivaoa , and a description of the ecological setting can be found under that species. Given the absence of aquatic habitats on the crest of Mt. Temetiu, and the notation on the holotype label that the specimen was taken on ferns, it is clear that C. robusta has a terrestrial ecology, but may occupy a specialized and unusual habitat.

Distribution. French Polynesia, Marquesas Islands, Hiva Oa ( Fig. 38 ).

Material examined. FRENCH POLYNESIA, Marquesas Islands, Hiva Oa: 1 female, Temetiu Summit , 4160 ft., on ferns 20 January 1932, leg. LeBronnec (holotype, BPBM) .

Figures

FIGURE 38. Distribution of endemic Hydrometridae species in the southen Marquesas Islands. Circles = Marquesametra hiavoa n. sp.; square = Chaetometra robusta.

FIGURES 5–8. Photographs of habitat for Marquesametra hivaoa n. sp. on Mt. Temetiu, Hiva Oa, Marquesas Islands, CL 6016 and CL 6031. 5. View of the Mt. Temetiu summit ridge in 2001, with survey camp visible as a blue tarp shelter to the center right of the frame, at an elevation of approximately 1100 m, CL 6031. 6. Dense cloud forest vegetation along the Mt. Temetiu summit ridge, including ferns, Freycineta arborea, and moss-draped Metrosideros collina trees in the upper portion of the frame, the latter supporting M. hivaoa. 7. Dr. J. T. Polhemus applying pyrethrin fog to a mossy tree in search of M. hivaoa. 8. Detail of moss and fern habitat on Mt. Temetiu harboring M. hivaoa.

FIGURES 35–37. Chaetometra robusta, holotype, structural details. 35. Lateral view. 36. Dorsal view. 37. Head.