Tunicotheres moseri (Rathbun, 1918) presents a rare case of post-hatching parental care not recorded previously among brachyuran decapods. The complete larval development takes place within a brooding enclosure of the parental female, formed by flexure of the broad abdomen against the sternum. The first crab instar is the earliest stage observed to leave this enclosure, doing so without active help from the parental female. The development of stages preceding the first crab was investigated by in vitro culture of eggs obtained from ovigerous crabs inhabiting the atrial cavity of the tunicate Phallusianigra Savigny, 1816, in Venezuela. Eggs were hatched in the laboratory and reared through two zoeal stages and the megalopa. Additional samples of the larval stages were obtained directly from abdominal enclosures of aquarium-held females. All larval stages were described and illustrated in detail. Morphological comparisons were made between larvae from two different populations. Comparisons were also made with other previously described larvae of Pinnotherinae, which led us to conclude that Tunicotheres should not be assigned to the Pinnotherinae sensu stricto. Relationships between the three known disjunct populations assigned to T.moseri remain questionable, especially since the potential for larval dispersal appears to be very limited.Tunicotheres moseri representa un caso raro de cuidado parental de los estadios posteriores de la eclosión larval, que no ha sido documentado con anterioridad en decápodos braquiuros. Todo el desarrollo larval transcurre en la cavidad comprendida entre el abdomen y la placa esternal de la hembra. El primer estado juvenil es el primero que abandona la cavidad y lo hace sin ayuda de un movimiento activo de abdomen de la hembra.Peer reviewed