Figs. 3a-d

Basic patterns. Scale-bars: 50 μm.

a. Type 2-3. Rays 2 and 3 are grouped, arising first and together from the common trunk of rays 2 to 6; rays 4 to 6 have a common trunk and diverge at the same level. Ex: Paraheligmonella interrogans (Lent & Freitas, 1938). After Durette-Desset (1968b), modified.

b. Type 2-2-1. Rays 2 and 3 are grouped, arising first and together from the common trunk of rays 2 to 6; ray 6 arises at the same level as ray 3; rays 4 and 5 are the last to diverge. Ex: Heligmostrongylus crucifer (Travassos, 1943). After Travassos (1943), modified.

c. Type 1-3-1. Rays 2 and 6 arise first and at the same level from the common trunk of rays 2 to 6; rays 3 to 5 have a common trunk. Ex: Hypocristata tercera Durette-Desset & Guerrrero, 2006. In this case ray 3 diverges first from the common trunk of rays 3 to 5 in the right lobe and at the same level as ray 5 in the left lobe. After Durette-Desset & Guerrrero (2006), modified.

d. Type 1-4. Ray 2 arises first from the common trunk of rays 2 to 6; rays 3 to 6 have a long common trunk. Ex: Fuellebornema bocqueti (Durette-Desset, 1970a). In this case ray 3 diverges at the same level as ray 6 on the common trunk of rays 3 to 6. After Durette-Desset (1970a), modified.

Figs. 3e-h

Intermediary patterns. Scale-bars: 50 μm.

e. Type 2-3 t 2-2-1. Rays 2 and 3 are grouped, arising first and together from the common trunk of rays 2 to 6; rays 4 to 6 have a common trunk; ray 6 diverges close to the level of the divergence of ray 3 and proximally to that of rays 4 and 5. Ex: Neoheligmonella acomysi Durette-Desset & Gibson, 1990. In this case rays 2 and 3 are apposed for much of their length. After Durette-Desset & Gibson (1990), modified.

f. Type 2-2-1 t 1-3-1. Rays 2 and 6 arise first and at the same level from the common trunk of rays 2 to 6; rays 3 arise just distally to the level of divergence of rays 2 and 6; rays 4 and 5 are the last to diverge. Ex: Pudica pudica (Travassos, 1921). After Cassone & Durette-Desset (1991), modified.

g. Type 1-3-1 t 1-4. Rays 2 arise first from the common trunk of rays 2 to 6; rays 6 arise slightly distally to the level of divergence of rays 2 and proximally to that of rays 3; rays 3 to 6 have a short common trunk. Ex: Spalacina yanchevi Biserkov, Durette-Desset & Genov, 1995. After Biserkov et al. (1995), modified.

h. Type 2-2-1 t 1-4. Rays 2 arise first from the common trunk of rays 2 to 6; rays 3-6 have a short common trunk; rays 6 arise at the same level as rays 3; rays 4 and 5 are the last to diverge. Ex: Hypocristata anguillula (Durette-Desset, 1971). Ray 3 is still grouped with ray 2 since its extremity supports the ventral lobe. After Durette-Desset (1971), modified.