Haementeria molesta

External morphology

Body elliptical and flattened. Individuals reach a total length of approximately 22 mm. The ratio of total length to maximum body width ranges between 3.2 and 3.6. The annuli are subdivided dorsally, though the secondary transverse furrow is occasionally inconspicuous. Ventrally, the somites are pentamerous; however, in certain specimens, this subdivision of the anterior and posterior annuli within each segment is not discernible. Nevertheless, annuli a1 and a3 are invariably larger than a2. In none of the 37 specimens examined is both the dorsal and ventral subdivision simultaneously absent; that is to say, if the annuli appear undivided dorsally, the secondary furrow is visible ventrally between a1 and a3, or vice versa. A single median dorso-longitudinal row of low-relief tubercles is present exclusively on the neural annuli (a2), though this row is frequently absent. There are four series of bar-shaped sensilliferous papillae: two oblique paramedian series and two nearly horizontal intermediate series. This arrangement corresponds to the indication of five rows of papillae provided in the original description. The mouth is situated at the level of II/III. Two eyes are located on segment III (annuli a1 and a2). The capitulum is formed by segments I through IV; however, if one includes the post-buccal annulus—formed by the fusion of annuli Va1, Va2, and Va3—the capitulum would be considered to extend from segment I through V. The gonopores are separated by a single annulus.

Habitat & range

Habitat

Freshwater

Region

South America

Recorded from

Brazil, Uruguay

Junior synonyms

Placobdella molesta