INSECTS AND ALLIES (ARTHROPODA) 



159 



cosmopolitan O bacoti (Hirst), a species associated with 

 rodents, particularly rats. These mites are among the 

 seven parasitic Mesostigmata reported for Micronesia by 

 Wilson (1967). G/ypt/io/aspis asperrima (Berlese) is one of 

 five macrochelids reported for Micronesia by Krantz 

 (1967); it is described from Java and reported for Palau 

 and the Marshalls (Arno); some of the specimens are from 

 a palm log (Palau). 



ixodida (Metastigmata): Marshalls 2, Enewetak 1 — The 

 ticks, reviewed by Kohls (1957), now comprise at least six 

 species in Micronesia. Kohls reported Rhipicephalus 

 sanguineus (Latreille) for the Marianas and Gilberts; earlier, 

 Schnee (1904) reported it for the Marshalls (Jaluit). This 

 cosmopolitan tick is associated mainly with the dog. The 

 Ornithodoros we list for Enewetak is from collections from 

 two species of noddies and their nests and possibly from 

 three additional species of sea birds from Enewetak (Bush- 

 man, Parker, and Johnson, 1963). This tick is widespread 

 on oceanic islands of both hemispheres, including Hawaii. 



Actinedida (Prostigmata): Marshalls 4, Enewetak 

 1 — Balaustium and Calorema are not identified further; the 

 former is reported for Enewetak and the latter for 

 Kwajalein. Two species of Tetranxjchus are reported for 

 Kwajalcin by Sugerman (1972a, 1979); T. cinnabahnus 

 (Boisduval) is known from North America and India, and 

 T. tumidus Banks is reported for the United States, Puerto 

 Rico, and Guam. 



Oribatida: Records are lacking for the Marshalls, 

 though the group is certainly expected there. Micronesian 

 oribatids are beginning to be reported upon by Sengbusch 

 (1982a, b), who described two lohmnanniids endemic to 

 the Carolines (Yap, Ponape) belonging to an ancient group 

 of Gondwanan origin. 



MYRIAPODA 



The Micronesian myriapod fauna is poorly sampled, 

 with only chilopods and diplopods reported for the 

 Marshalls. Pauropods are reported only from Palau and 

 Guam (Remy, 1957). Symphylans apparently remain 

 unreported for Micronesia, though they may be expected 

 on remote islands. Hanseniella orientalis (Hansen), for 

 example, is an Indo-Australian species that also reaches 

 Samoa and the Marquesas (Adamson, 1932; Silvestri, 

 1939). Four other species are reported for Hawaii 

 (Scheller, 1961). 



Chilopoda 



Marshalls 1, Enewetak — The only centif)cde defi- 

 nitely reported for the Marshalls is Scolopendra morsitans 

 Linnaeus, a widespread species reported for Jaluit 

 (Schnee, 1904). Townes (1946) stated that Scolopendra 

 occurs on practically every island and is moderately com- 

 mon, but Enewetak was not sjjecifically indicated. 



Diplopoda 



Marshalls 3, Enewetak 1 — Two unidentified millipedes 

 representing Poli;xenus and Trigonoiu/us are reported for 



the Marshalls. Oxidus gracilis (Koch), recently collected 

 from Enewetak, occurs throughout the Pacific; it is com- 

 mon in Hawaii and is easily transported in soil through 

 commerce (Williams, 1931). 



INSECTA 



Apterygota 



Only two orders (Thysanura and Collembola) of these 

 primitive, wingless insects have been reported for 

 Enewetak to date. Although only a few species have been 

 reported, further records can be expected, possibly includ- 

 ing proturans and diplurans. 



Thysanura 



Marshalls 1, Enewetak 1 — At least one species of Lep- 

 ismatidae is reported for the Marshalls, questionably identi- 

 fied as Lepisma saccharina Linnaeus (Schnee, 1904). 

 Townes (1946) observed a lepismatid on Enewetak, but it 

 was not identified. 



Collembola 



Marshalls 2, Enewetak 2 — The Isotomurus and Seira 

 we list for Enewetak were recently collected and appear to 

 be the first records of the order for the Marshalls. Uchida 

 (1944) studied earlier collections from Micronesia (Mari- 

 anas and Carolines), with more than half of the 13 species 

 treated appearing to be endemic. Mari Mutt (1979) added 

 another endemic species to the Carolines fauna (Ponape). 



Pterygota 



These are insects that have attained flight, including 

 those that have secondarily lost the capability. The bulk of 

 the insects belong to this group, and they are discussed 

 below either at the ordinal or familial level. 



Odonata 



Marshalls 7, Enewetak 2 — Only one damselfly (Zygop- 

 tera), Ischnura aurora (Brauer), reaches the Marshalls but 

 not Enewetak; it has Oriental affinities. Six dragonflies 

 (Anisoptera) reach the Marshalls, and two are recorded for 

 Enewetak. Of the latter, the Pantala we list for Enewetak 

 is tropicopolitan and widespread in the Pacific, including 

 Hawaii. The Tramea we list is a sight record by E. H. 

 Bryan, Jr.; it is a North American sfjecies that reached 

 Hawaii late last century and was likely transported from 

 Hawaii to Enewetak. The four other anisopterans reaching 

 the Marshalls are widespread in Micronesia and beyond, 

 with three found in Australia or on continental islands 

 bordering the western Pacific, and one ranging from Africa 

 through Asia and Australia. The Micronesian fauna, stud- 

 ied by Asahina (1940) and reviewed by Lieftinck (1962), 

 comprises 48 species or subspecies, with endemism about 

 52%. The monotypic genus Pacificothemis is endemic to 

 the eastern Carolines (Ponape). 



