Thalassaphorura (formerly Protaphorura) encarpata is a 'tramp' species that occurs all over the World in glasshouses. There are a few literature records from such habitats in England although I have not seen any specimens from these localities. Chowdhuri, (1958) described the species parthenogenetica from Silwood Park, Ascot but the locality was out of doors and it seems likely that there was some confusion as to the source of his material. All the mature specimens of parthenogenetica in the NHML collection are in a poor state of preservation except for one adult female from a 'laboratory culture' which fits the description of Thalassaphorura encarpata. Indeed, parthenogenetica was sunk as a junior synonym of Protaphorura hortensis (Gisin, 1949) by Gisin (1960). Protaphorura hortensis was in turn sunk as a junior synonym of Thalassaphorura encarpata by Fjellberg (1998).
     Thalassaphorura encarpata has no trace of a furca. The empodium is almost same length as the claw and does not possess a lamella (Fig. 1). The post-antennal organ has about 25 simple vesicles and there are two anal spines. The dorsal side of the first thoracic segment has 2+2 pseudocelli (PSO) (Fig. 2). The typical PSO formula is 32/233/33343.
     Although placed in the genus Thalassaphorura, features of the morphology of encarpata suggest that 'the origin and evolutionary history of this introduced species is distant from that of the rest of the genus' (Fjellberg, 1998). Thalassaphorura encarpata should be looked for in glasshouses everywhere.

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Fig. 1 (above): Foot of the third leg of Thalassaphorura encarpata reared from a laboratory culture at Silwood Park by D.K. Choudhuri in 1958. Unfortunately the specimen is in poor condition but enough diagnostic features are present to validate the identification.

Fig. 2 (above): Dorsal side of the first thoracic segment (th1) of the same specimen of Thalassaphorura encarpata shown in Fig. 1. There are two pseudocelli on the left (L1, L2) and two on the right (R1, R2).  These are much clearer in the original specimen than in the photograph.