John T. Polhemus

Global trends in the description of aquatic and semiaquatic Heteroptera species, 1758-2004

Species description trends for the 4782 species of aquatic and semiaquatic Heteroptera (Gerromorpha, Nepomorpha, and Leptopodomorpha) named during the 246 year interval from 1758 through 2004 are analyzed in regard to number of species descriptions per year and cumulative number of species. These data are graphed both on a world basis, and for seven major zoogeographic regions (Palearctic, Nearctic, Neotropical, Afrotropical, Oriental, Australian and Pacific). This analysis reveals that our taxonomic knowledge of aquatic and semiaquatic Heteroptera, as measured by species descriptions, has accumulated at a progressively faster rate over time when assessed on a world basis, albeit in an episodic and uneven fashion, with peaks of high activity interspersed with periods of relatively low output. When examined at the level of individual zoogeographic regions, the accumulation of taxonomic descriptions is seen to be pronouncedly episodic, and contingent upon the productivity of particular regional experts during the courses of their careers, with just ten authors accounting for over 40 percent of all currently accepted species descriptions. Species accumulation curves, based on published descriptions, indicate that description of extant aquatic and semiaquatic Heteroptera species is nearly complete for the Palearctic and Nearctic regions, and well advanced for the Neotropical region. The Oriental and Australian (including New Guinea) regions show continuing sharp upward trends, indicating that these regions are still far from completely documented. The flattening of the description accumulation curves in the Afrotropical and Pacific regions is interpreted to be an artifact produced by a relative paucity of recent taxonomic work in these regions, and thus not truly indicative of well documented biotas in these areas. Rates of species description in aquatic and semiaquatic Heteroptera were highest immediately after World War II, a level of productivity that has been approached once again in recent decades. If the current average rate of 51 species descriptions per year can be maintained, the estimated 1100 species of aquatic Heteroptera remaining undescribed on a global basis will be formally named within the next 25 years, basically completing the taxonomic documentation of this group.

New Species of Microveliinae (Heteroptera: Veliidae) from the Raja Ampat Islands

2000), the authors have described six new genera and many new species of Microveliinae occurring on the island of New Guinea. Recent investigations have now shown that certain of these genera also occur to the west of New Guinea proper, in the islands of the Raja Ampat group. The current paper describes five new species of Microveliinae from these islands, providing a more comprehensive view of this regional biota. Additional species of Microveliinae, including representatives of the widespread and speciose genus Microvelia, also occur on the islands of the Raja Ampat group, and these taxa will be dealt with in subsequent publications. The Raja Ampat Islands are a mountainous archipelago lying immediately to the west of the Vogelkop Peninsula, or Bird’s Head, of far western New Guinea. The name of the group means ‘four rajas’ in Malay, referring to the former local rulers who were based in Waigeo, Salawati, north Misool (Waigama) and south Misool (Lelintah), and is also shown on some maps by the variant spellings Radja Ampat or Raja Empat, the latter being most correct in current Indonesian orthography. The group contains several relatively large islands, notably Misool, Salawati, Batanta, and the nearly connected pair of Waigeo and Gam, plus numerous other smaller islands and islets. The general topography of the group is rugged, although the highest summits of the major islands are not exceptionally tall, reaching 565 m on Misool, 931 m on Salawati, 1183 m on Batanta, and 1000 m on Waigeo/Gam. The surface geology of the islands is predominantly limestone, but their interiors also contain complex exposures of other sedimentary and metamorphic rocks, and as a result many of the streams and rivers in the archipelago have beds of cobbles and gravels representing highly varied rock types. Although the Raja Ampat group has long been known as an area of endemism for many groups of organisms, entomological surveys in the islands have been sporadic and haphazard, particularly in regard to aquatic groups. The most significant previous collections were made by G. Evelyn Cheesman, who visited Waigeo in 1938, penetrating inland to the mountains surrounding the prominent peak of Mt. Nok, or Buffelhorn. Damselfly collections were also made by M. A. Lieftinck during a visit to Misool in 1948. In 1991, the authors made collections of aquatic Heteroptera on Salawati, in both the mountains along the northern margin of the island and in the extensive lowlands of the south; selected groups from these collections were subsequently analyzed in the context of larger regional monographs (Polhemus & Polhemus 1993, 1996, 1997). More recently, in April 1999, the first author was able to make extensive collections of aquatic Heteroptera and other aquatic in-

A new genus of Helotrephinae from Peninsular Malaysia and Borneo (Heteroptera: Helotrephidae)

family Helotrephinae has seen a recent flurry of taxonomic activity. The genus Helotrephes was reviewed by Zettel & Polhemus (1998), and further new species were subsequently described by Nieser & Chen (1999), and by Zettel (2000a, 2000b, 2001b). This genus is now thought to be reasonably well known, with only a few additional undescribed species remaining in collections. The genus Hydrotrephes, by contrast, contains many undescribed species distributed throughout Southeast Asia, the Malay Archipelago, and the Philippines. Polhemus (1997) provided the first review of this genus in nearly a half-century, and additional new species were subsequently described by Zettel (1998, 2000b, 2001a), Nieser & Chen (1999) and Kovac & Papacek (2000). The genus Heterotrephes also occurs in Southeast Asia, with one species from Taiwan (Zettel did not formally recognize Heterotrephes from Borneo, but says in litt. that the Hydrotrephes mirus group belongs with that genus), while the genus Esakiella is known only from Africa and Madagascar. In the present paper we add a fourth genus, Ascetototrephes gen. n., to the known helotrephine fauna of Southeast Asia. The species in this new genus are generally larger in overall size than those of the other three genera found in the region, and are to date known only from Borneo and Peninsular Malaysia. All measurements are given in millimeters. Specimen repository abbreviations are as indicated in the acknowledgments. Type repositories are as indicated under each species; paratypes are in the collections of the Smithsonian Institution, Washington, D. C. (USNM); Naturhistorisches Museum, Vienna (NHMW); and the J. T. Polhemus Collection, Englewood, Colorado (JTPC).

Revision of the genus Ochterus (Hemiptera: Heteroptera: Ochteridae) in Mesoamerica and the United States

The genus Ochterus is revised for Mesoamerica and the continental United States. The fauna as currently understood contains ten previously described species, and the following ten new species described herein: O. chiapensis from southeastern Mexico, O. costaricensis from Costa Rica, Panama and El Salvador, O. explanatus from western Mexico, O. mexicanus from central Mexico, O. obscurus from Costa Rica, O. ovatus from southeastern Mexico, O. panamensis from Panama, O. pseudorotundus from northeastern Mexico, O. shepardi from Costa Rica, and O. smaragdinus from southeastern Mexico. Ochterus flaviclavus Barber is shown to represent an intraspecific color morph of O. banksi Barber and is synonymized under the latter species. Color photographs of the dorsal body and frons, as well as line drawings of male genitalic structures, are provided for all species treated, accompanied by distribution maps.

Ocyochterus irmae, a beautiful new species of Ochteridae (Heteroptera) from the Northern Andes

The new species Ocyochterus irmae is described from the Andes Mountains of Colombia and adjacent Ecuador. This species is only the second known in the genus, and the first in which male specimens have been available for dissection of the genitalic structures. A new record is also provided for the previously described O. victor (Bolivar), constituting only the fourth known specimen of this taxon since the original description in 1879, and the first new collection in over 90 years. Color photographs of the dorsal habitus and anterior head are presented for both O. irmae and O. victor, as well as photographic figures of the male parameres, aedeagus, proctiger and pygophore for O. irmae, representing the first illustrations of the male genitalic structures in this genus. A distribution map for O. irmae and O. victor is also provided.

A NEW GENUS OF PTILOMERINE GERRIDAE (HEMIPTERA: HETEROPTERA) FROM FLORES, LESSER SUNDA ISLANDS

Abstract A new genus of Gerridae, Floresiobates, is described from the island of Flores in the Lesser Sunda Islands of eastern Indonesia, with F. lattini n. sp. as the type species. Floresiobates is compared with Rheumatogonus Kirkaldy and Jucundus Distant, and these three genera are considered on the basis of various shared character states to be closely related. Illustrations of key characters and a distribution map are provided, accompanied by a discussion of the ecological setting in which the type series was collected, and a consideration of the biogeographic implications of this discovery.