Table 1 Characteristics and requirements of extant sedentary/sessile kleptoparasitic interactions (from ref. 35; left) compared with early Cambrian brachiopod–tube interaction from the lower Cambrian (Stage 4) Guanshan Konservat-Lagerstätte (right).
From: An encrusting kleptoparasite-host interaction from the early Cambrian
Extant sedentary kleptoparasitic interaction | Guanshan brachiopod-encrusted tube interaction |
|---|---|
Interactions are long in duration, the kleptoparasite utilizes few hosts within its lifetime (sometimes only one) | Obligate and enduring interaction between kleptoparasitic encrusting tube-dwelling organisms and adult organophosphatic brachiopod host |
Extreme negative impact on the host is not possible because of limited ability to find a new host if the present one dies | Measurable negative non-fatal impact on host (Fig. 2); encrusting life habitus limits association to single host over lifetime |
One host might be sufficient | Obligate parasite–host interaction |
Individual items do not need to be large, as not much energy is expended by kleptoparasite to steal food and host feeding is continuous. Regular access to adequate food is necessary | Kleptoparasite an intercept filter feeder; steals proportion of inhalant particulate food stream generated by brachiopod. Brachiopod feeding almost continuous |
Life span of host exceeds a sessile kleptoparasite’s time to sexual maturation or hosts aggregate in heterochronous assemblages if kleptoparasite is sedentary | Life span of brachiopod and tube unknown, death of host kills parasite; host forms dense concentrations of clustered shells of variable size. Host and kleptoparasitic tube are sessile |
Host must not consume a large proportion of the kleptoparasite’s offspring, either during larval emergence or settlement | Unknown. Enduring geographically widespread occurrence of unique, obligate brachiopod–tube shell beds suggests successful larval recruitment for both taxa |
