Back
Biconidinium longissimum

Biconidinium longissimum, Islam, 1983

Holotype: Islam 1983, pl.1, fig.3
Locus typicus: Sheppey, England
Stratum typicum: Early Eocene

-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Islam, 1983, p. 84]:

Diagnosis:
Pericyst fusiform with one long apical horn and one equally long antapical horn having rounded or blunt tips; endocyst ellipsoidal to slightly fusiform; circumcavate or bicavate; both phragma chagrinate or granulate; paracingulum slightly helicoidal and sunken; parasulcus also slightly sunken; paratabulation indicated by linear thickenings in periphragm and given in generic diagnosis; archeopyle intercalary type 3I/3I, endoarcheopyle frequently indistinct.

Dimensions:
Holotype: pericyst 140 x 51 µm, endocyst 57 x 49 µm, lengths of apical horn 47 µm and antapical horn 36 µm.
Range: pericyst length 109(135)166 mµ, breadth 42(40)51 µm; endocyst length 47(44)57 µm, breadth 26(35)49 µm; lengths of apical horn 31(43)55 µm and antapical horn 31(44)55 µm.

-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Notes:
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.

Biconidinium longissimum Islam, 1983c, is fusiform, with the apical and antapical horns having rounded or blunt tips. Endocyst is circumcavate or bicavate. Both phragma are granulate or chagrinate. Goodman interpreted the tabulation as pyrodinioid and the archeopyle as apical. The homolog of 1' is exsert. Length overall 109-166 µm, breadth 42-51 µm, horns 31-55 µm.
Feedback/Report bug