VOL. 54, NO. 1, JANUARY 1978 
47 
the tribe Orchesellini (e.g. Womersley 1938, Salmon 1951). I am pre¬ 
sently revising this tribe and it has become evident that Mastigoceras 
is not a close relative of any other genus in this tribe. 
All orcheselline species which I have studied to date share a 
fundamental pattern of head macrochaetotaxy. The most 
conspicuous feature of this pattern is a line of setae extending from 
the mid line of the head to eyes G & H (see for example the figures of 
head chaetotaxy in Mari Mutt 1977a,b). Such a line of setae is absent 
in Mastigoceras. 
Other members of this tribe possess a tuft of many macro- 
chaetae on the anterior margin of the mesothorax (the collarette). 
This tuft is reduced to 9-10 setae in Mastigoceras. 
Besides head macrochaetotaxy and the reduction of the collarette, 
Mastigoceras has as unique features its reduced body macrochaeto¬ 
taxy, absence of scales on the furcula, and the morphology of the 
antennae. 
Stach (1960) restricted the tribe Orchesellini to include only the 
type genus Orchesella and remarked that additional tribes should be 
erected for groups of other genera in the tribe. It is quite apparent to 
me that a new tribe should be erected for Mastigoceras. I hesitate, 
however, to establish such a taxon in this paper because it is unclear 
at this time how many tribes will be erected for the genera of the old 
tribe Orchesellini. Suffice it to note here that Mastigoceras is not a 
close relative of any other orcheselline genus but belongs in a group 
by itself. 
Literature Cited 
Cassagnau, P. 1963. Collemboles d’Amerique du Sud, II. Orchesellini, Paronellinae, 
Cyphoderinae. Biol. Amer. Australe, C. Delamare Deboutteville & E. Rapoport, 
Eds. CNRS, Paris, 2: 127-148. 
Gisin, H. 1960. Collembolenfauna Europas. Ed. Mus. Hist. Nat. Geveve, 1960, 312 pp. 
Handschin, E. 1924. Neue myrmecophile und termitophile Collembolenformen aus Sud- 
Amerika. Neue Beitr. Syst. Insektenk. 3:13-19, 21-28. 
Mari Mutt, J.A. 1977a. A new species of Heteromurus from the Solomon Islands (Collem- 
bola: Entomobryidae). Pan-Pac. Entomol. 52(4): 326-330. 
Mari Mutt, J.A. 1977b. Dicranorchesella, a new genus of springtails from Mexico (Collem- 
bola: Entomobryidae). Proc. Entomol. Soc. Washington 79(3): 377-382. 
Salmon, J.T. 1951. Keys and bibliography to the Collembola. Zool. Pub. Viet. Univ. Coll. 8: 
1-82. 
Salmon, J.T. 1964. An Index to the Collembola. Bull. Roy. Soc. New Zealand 7:1-651. 
Stach, J. 1960. The apterygotan fauna of Poland in relation to the world fauna of this 
group of insects, tribe Orchesellini. Polska Akad. Inst. Zool., 1960,151 pp. 
Womersley, H. 1939. Primitive insects of South Australia. Government Printer, Adelaide, 
322 pp. 
