According to De Lotto (1965a): Young living adults flat, emerald-green in color, with some black or very dark brown minute dots set in irregular radiating rows near the margin of the body; old adults flattish, color evenly dark brown.
Kilifia deltoides is similar to both K. acuminata and K. americana by having hind 2 pairs of legs conspicuously larger than front legs; hind 2 pairs of coxae with unusual cavity laterodistally; anal plates with anterolateral margin longer than posterolateral margin; anal plates in middle of abdomen; without tubular ducts. Kilifia deltoides differs by having apically acute tibio-tarsal spur greater than ¼ length of tarsus (shorter or absent in K. acuminata and K. americana).
U.S. quarantine notes
This species was intercepted 3 times at U. S. ports-of-entry between 1995 and 2012, with specimens originating from Guam, India and The Philippines. Specimens were intercepted on Ixora from Guam. Two older interception records are from The Philippines on Mangifera and Thailand also from Mangifera. ScaleNet includes hosts in 5 plant families and distribution records include Comoros, Kenya, Tanzania and Zanzibar in the Afrotropical region, China, Indonesia (Java) and Malaysia (Sarawak) in the Oriental zoogeographic region. No other species of Kilifia other than K. acuminata (Signoret), K. americana Ben-Dov and K. deltoides have been taken at a U. S. port-of-entry.