BIOTIC ASSOCIATIONS OF COCKROACHES — ROTH & WILLIS 23 1 



Rhipidioides mollis Riek 



Natural host. — Rohshelfordia longiuscula or Rohshelfordia circum- 

 ducta, Australia Capital Territory (Riek, 1955). 



Rhipidioides rubricatus Riek 



Natural liost. — Choristinia sp. and Choristimodes sp., Australia 

 Capital Territory (Riek, 1955). 



Riekella australis (Riek) 



Synonymy. — Nephrites australis Riek [Selander, 1957]. 

 Natural host. — Cutilia sp., Australia Capital Territory (Riek, 

 1955) • Two females emerged from one host. 



Riekella nitidioides Selander 

 Synonymy. — Nephrites nitidus of Riek not Shuckard [Selander, 



1957]. 

 Natural host. — Platyzosleria sp., Tasmania (Riek, 1955). 



Riekella sp. 



Synonymy. — Nephrites sp. [Selander, 1957]. 



Natural host. — Platysosferia castanea, Australia Capital Territory 

 (Riek, 1955). 



Biology of Australian Ripidiini. — The Australian species of Ripi- 

 diini are parasites of apparently endemic, ground-dwelHng species of 

 cockroaches. There is some correlation between host subfamily and 

 parasite genus : Riekella spp. [ = Nephrites] have only been bred from 

 Blattinae. Rhipidioides spp. occur only in the closely related Ecto- 

 biinae and Pseudomopinae. Neonephrites and Neorhipidius also occur 

 in the Pseudomopinae. Paranephrites occurs in the Panchlorinae. 

 There is some evidence that the parasitized cockroaches migrate onto 

 trees when the larval parasite is mature, as pupae have only been 

 found on the trunks of eucalyptus trees. In all species the larva leaves 

 the host dorsally through an intersegmental membrane. The host 

 continues to live for a few days after the parasite emerges. The larva 

 attaches itself to bark on the tree trunk by a few strands of silk before 

 pupating. The larviform, vringless female remains near the pupal skin 

 and is sought out by the winged male. The eggs are laid in a mass 

 around the pupal skin (Riek, 1955). 



Ripidius = boissyi Abeille 



Balduf (1935) lists Ripidius boissyi as parasitic on nymphs of 

 Ectobius pallidus giving Abeille de Perrin (1909) as a source for this 



