Detriturus (formerly Onychiurus) jubilarius does not possess anal spines and the furca is absent. The post-antennal organ (PAO) contains about 12 complex vesicles. The dorsal pseudocelli (PSO) formula is 33/133/33354, with the three PSO behind the antennae arranged in a triangle (Fig. 1). The dorsal side bears lanceolate setae (Fig. 2) arranged as 2/011/11101 on each side in addition to normal setae (i.e. there are two pairs of lanceolate setae on the head, and one pair on thoracic segments 2 and 3, and abdominal segments 1, 2, 3, and 5). The tibiotarsi of the legs each have 11 distal setae (Figs. 3, 4, 5). A small inner tooth on the claw is absent, and males have a row of eight enlarged ventral setae on both the second and third abdominal segments (abd2, abd3). I have only seen two specimens which fit the above description. They were 0.8 mm in length and were collected from fields at the Weed Research Organisation, Kidlington, Oxfordshire by Harold Gough.
     
Detriturus jubilarius should be looked for in collections of Collembola from agricultural soils as its small size makes the species easy to overlook.

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Figs. 3 (top), 4 (middle) and 5 (bottom): Tibiotarsus of the third leg of the same specimen of Detriturus jubilarius shown in Fig. 1 at three levels of focus. The arrows point to the eleven tibiotarsal setae.

Fig. 1 (above): Dorsal surface of the head of Detriturus jubilarius collected from Kidlington, Oxon. in October 1968 by Harold Gough. There are three ocelli arranged in a triangle posterior to the base of each antenna.

Fig. 2 (above): Dorsal surface of the third abdominal segment of the same specimen of Detriturus jubilarius shown in Fig. 1. The arrows (*) point to the lanceolate setae.