44 
THE PAN-PACIFIC ENTOMOLOGIST 
Eight eyes on each side of head (Fig. 8), G & H small but well developed. Labral chaeto- 
taxy following formula 5,5,4,; all setae smooth. Apex of labrum without spine like or cone 
like projections. Labial chaetotaxy as in figure 5. Differentiated seta of the outer labial 
papilla small, far from reaching apex of its papilla (Fig. 7). Maxillary palp (Fig. 6) with 
apical and subapical seta. Dorsal head macrochaetotaxy as in Fig. 1. Venter of head with 
numerous long ciliated setae. Collarette reduced. 
Tibiotarsi devoid of smooth setae with the exception of opposite seta to tenent hair 
present on metathoracic legs. Claw structure as in Fig. 4. Unguis always quadridentate. 
Unguiculus with very small outer tooth. Tenent hair long, apically strongly clavate. Abd. 4 
dorsally not over 1.5 times longer than Abd. 3. Dorsal body macrochaetotaxy as in Fia. 1. 
Manubrium dorsally with a lasiotrichium placed on the basal medial portion of the seg¬ 
ment and with numerous short and long slightly or conspicuously ciliated setae. No 
smooth setae found upon manubrium but a pair of these present on proximal dorsal por¬ 
tion of dentes. Dental spines absent. Mucro with two teeth and basal spine. 
Material Examined and Repository : 1) Brazil, Minas Gerais, Sul de Minas, in nests of 
Camponotus rufipes, April 29, 1922. 2 syntypes. 2) Brazil, 10-8-27, 22 specimens (no other 
data). 3) Sao Paolo, 7 specimens (no other data). 4) Pava, 1 specimen (no other data). 
Naturhistorisches Museum, Basel, Switzerland, has the specimens from locality no. 1 
and two specimens from locality no. 2. Other specimens from localities 2, 3 & 4 are in the 
Illinois Natural History Survey. 
This genus being monotypic, the generic diagnosis suffices to se¬ 
parate the species from any other Collembola. The length of the 
antennae, the head and body macrochaetotaxy, the distribution of 
scales, and the reduction of the collarette (a tuft of macrochaetae on 
the anterior margin of the mesothorax) are all characteristics peculiar 
to this genus. 
Handschin’s original description of Mastigoceras camponoti 
ascribes to this species four segmented antennae. Cassagnau (1963) 
showed the antennae to be five segmented. 
The statement by Salmon (1964: 132) that Gisin (1960) considered 
this genus as a synonym of Heteromurus Wankel is a mistake. Gisin’s 
position concerned Typhlopodura Absolon, erected for a European 
cave species with long antennae. 
The Systematic Position of Mastigoceras 
As stated earlier, Mastigoceras has been considered to belong in 
Figs. 1-7, Mastigoceras camponoti. Fig. 1, Distribution of head and 
body macrochaetae (each dot represents a seta) and lasiotrichia. Only 
the lasiotrichia figured were found but more are probably present. 
Fig. 2, Dorsal habitus and pigmentation. Fig. 3a, Lateral habitus and 
pigmentation. Fig. 3b, First antennal segment indicating sub¬ 
division into Ants. 1 & 2. Fig. 4, Claw complex of metathoracic leg. 
Fig. 5, Chaetotaxy of base of labium. Fig. 6, Maxillary palp. Fig. 7, 
Outer labial papilla and its differentiated seta. 
