INSECTS AND ALLIES (ARTHROPODA) 



169 



Micronesia (4) or also occurring in Australia, Philippines, 

 and Hawaii (1). The last is also reported for Enewetak. 

 One of the restricted species, Cirrospdoideus /u/Zauxiyi Y. 

 and 1., is reported only from Ebon. Micronesian fauna 

 comprises 35 species, with endemism about 60%. Only 

 three of the 1 1 species occurring on Caroline atolls and 

 one of the two species occurring in the Gilberts are also 

 present in the Marshalls, making the atoll eulophid fauna 

 irregular. 



Evaniidae (Towncs, 1958): Marshalls 2, Enewetak 

 1 — These species are either circumtropical [Euania 

 appendigaster (Linnaeus)] or Malayan-Melanesian and 

 extending farther into the Pacific, including Enewetak and 

 Hawaii (Szeptigetella). Micronesian fauna comprises three 

 species, with none endemic. 



Formicidae: Marshalls 22, Enewetak 1 — Ants from 

 Enewetak are poorly sampled, and the 13 species listed by 

 Cole (1949) for Bikini should also occur there. The sole 

 species we list for Enewetak, Monomorium pharaonis (Lin- 

 naeus), is cosmopolitan. Species reported for the Marshalls 

 are widespread (11), Oriental (8), more or less restricted to 

 the Pacific (2), or Australian (1). At least 13 of these ants 

 also occur in Hawaii, being mainly "tramp species" that 

 are widely distributed by commerce. Wilson and Taylor 

 (1967) treated the Polynesian fauna, which includes many 

 species of possible occurrence in Micronesia. 



Ichneumonidae (Townes, 1958): Marshalls 2, Enewetak 

 1 — The polytypic Echthromorpha agrestoria Swederus 

 ranges from Africa through Asia into the Pacific and 

 includes three subspecies endemic to Micronesia, plus a 

 further subspecies (insidiatorj of Indonesian-Melanesian dis- 

 tribution that is reported for Enewetak. The other species, 

 Trathala flauoorbitalis (Cameron), is Oriental. Both species 

 occur in Hawaii. Micronesian fauna comprises 33 species, 

 with endemism probably less than 60%. Only 12% are 

 reported for isolated atolls, but none occurs exclusively on 

 atolls. 



Megachilidae (Krombein, 1950): Marshalls 3, Enewetak 

 2 — Two species of Megachile reported for Enewetak arc 

 either of Oceanian distribution (hedlei/i) or possibly of 

 Philippine origin and are now found throughout Micronesia 

 and Hawaii (Ju/Zauxiyij. A third species, M. umbripennis 

 Smith, is Oriental and was not seen in Micronesia until 

 after World War II; it is now reported for the Marianas and 

 Marshalls and also occurs in Hawaii. Micronesian fauna 

 comprises eight species, with endemism about 38%. 



Scclionidae: Marshalls 2, Enewetak — Two unidenti- 

 fied species are reported for Kwajalein (Sugerman, 1979); 

 they represent Telenomus and possibly Caloteleia. 



Sphecidae (Krombein, 1949, 1950): Marshalls 11, 

 Enewetak 4 — The species from Enewetak are from con- 

 tinental areas, probably reaching Pacific islands, including 

 Hawaii, through human activities. Species reported for the 

 Marshalls are widespread in the Old World (2), Oriental 

 region (3), New World (3), or limited to Pacific islands (3). 

 Species in the last category all belong to Pison. Nine of 11 

 species reaching the Marshalls also occur in Hawaii, includ- 

 ing the four reported for Enewetak. It is probable that at 

 least some of the sphecids gained entry to the Marshalls 



via Hawaii Micronesian fauna comprises 30 species, with 

 endemism about 17%. 



Vespidae (Krombein, 1949): Marshalls 4, Enewetak 

 4 — The species of Pachodi^nerus and Polistes we list for 

 Enewetak are from North America, introduced to Hawaii 

 and Micronesia; the Ropalidia is Malayan. The distribution 

 of Odynerus sp. is undetermined, but there are three 

 endemic congeners described from the Marianas. Microne- 

 sian fauna comprises 12 species, with endemism about 

 58%. 



COLLECTION RECORDS 



Insects and Allies of Enewetak Atoll 



Taxa are listed in the same order as given in the 

 checklist (Table 1). Collection records reported are abbre- 

 viated and include, when known, the islet, month, year, 

 and surname of collector. The specific islet was unclear in 

 some cases, and these arc listed as "?Islet" or by a 

 descriptive phrase (see first entry). The name of the deter- 

 miner is included when the particular specimens cited were 

 previously unreported for Enewetak. 



Class ARACHNIDA 

 Order SCORPiONIDA 

 Family ISCHNURIDAE 

 Hormurus australasiae Fabricius 



"On every island visited": May 1946, Townes. 



Order PSEUDOSCORPIONIDA 



Family ATEMNIDAE 



Oratemnus samoanus whartoni Chamberlin 



Enewetak Islet: Nov. 1944, Dybas and Edgar. Japtan Islet: 



Oct. -Nov 1944, Dybas 

 Family CHERNETIDAE 

 Haplochernes insulanus Beier 



Japtan Islet: Nov 1944, Dybas. 

 Family CHTHONIIDAE 

 Lecbijtia sakagarnii Morikawa 



Enewetak Islet: Nov. 1944, Dybas. Japtan Islet: Nov. 1944, 



Dybas 



Order ARANEAE 

 Family ARANEIDAE 

 Araneus theis (Walckenaer) 



Ikuren Islet: Sept 1975, Cheng. Medren Islet: Sept. 1975, 



Cheng — det by L J Pinter. 

 Family CLUBIONIDAE 

 Chiracanthium diuersum Koch 



Japtan Islet: Sept. 1975, Cheng. Medren Islet: Sept. 1975, 



Cheng — det. by L, J. Pinter. 

 Family DIPLURIDAE 

 Masteria hirsuta Koch 



Enewetak ?Islet: June 1946, Morrison. 

 Family EUSPARASSIDAE 

 Heteropoda uenatoria (Linnaeus) 



Enewetak Islet: Sept 1975, Cheng— det by L. J. Pinter 



(determined from cast exoskeleton). 



