TABLE 1. Morphological terminology for pylonioids.
| Taxonomic specification | Terms | Definition | Reference |
| Key skeletal elements | microsphere (S1a) | The innermost shell (< 50 μm in diameter) in Spumellaria. Microsphere is considered to form at the initial skeletogenesis. It differs from the macrosphere by its size only. This corresponds to S1a. | De Wever et al. (2001); Dumitrica (1989) |
| girdle | One of pylonioid multiple shells. A girdle looks like an encircled band, a triangle outline composed of mutually oriented circular tests, or a set of large vaulted dome-shaped tests which are orthogonally arranged. For example, a girdle is constituted with two caps or two wings in Tetrapyle, with six cupolas in the Tholoniidae. | De Wever et al. (2001) | |
| cap | Portion of a girdle that develops from a previous skeletal part. The “circular test”, “dome-shaped test” and cupolar is a kind of cap. | Dumitrica (19895) | |
| wing | An incomplete cap. | Haeckel (1887) | |
| half girdle | An abstract word when it is not necessary to differentiate between “cap” and “wing”. | Haeckel (1887) | |
| cupola | Large vaulted dome of a cap. This is also termed as “dome-shaped test.” | Dumitrica (1989) | |
| gate | Gate is defined by the disclosed large space between part of a girdle and the previous skeleton, in the case of the Pylonioidea. This term is an abstract noun if it is not necessary to concern on the orientation of a gate. “Aperture” and “Tunnel” are used when one needs to explain about gates in consideration with its orientation. | Redefined herein | |
| aperture | An appearance of a gate that one can see an opening. | New | |
| tunnel | An appearance of a gate that one can see the wall that forms a gate. | New | |
| Pylonioid system | A set of one to four successive outer girdles. One set of the lateral, transverse and sagittal girdles in the sense of Jørgensen (1905). This term may be written simply as “system.” | Dumitrica (1989) | |
| S1a-girdle | The pylonioid system that directly develops from the microsphere (S1a). This corresponds to S1a-girdle. | Dumitrica (1989) | |
| central combination | The skeletal structure comprised with a microsphere and the S1a-girdle. The development pattern of the a-girdle with the S1a is a key to specify family or subfamily position in Pylonioidea. | New | |
| band girdle | An encircle girdle to form a ring. | New | |
| joint part | The connection where two or more caps share. | New | |
| ring | One of Circodiscus multiple shells. A ring is encircled. | New | |
| di-clade corner/junction | A corner resulting from bending of a microspheric bar. | Dumitrica (1989) | |
| tri-clade corner/junction | A kind of a triple-junction on pore frame. An edged corner or a nodal point where three bars of pore frame unit. | Dumitrica (1989) | |
| pillar | A kind of bar, beam, rod and spine that are arisen from cupolas of an inner girdle. | Dumitrica (1989) | |
| Skeletal frame and structures | primary ray/spine (RB) | A kind of bar, beam, rod and spine that directly extends from a tri-clade corner. RL-primary ray (spines) originating in a di-clade bar corresponding to one of the lateral edges of the hypothetical prism. | Dumitrica (1991) |
| dimensive beams/rods/spines (DR) | A kind of beam, rod and spine that orthogonally extends from the S1a. The term DR is mainly used if its orientation is not concerned. If its orientation is concerned under some coordinates, they are called like “a sagittal beam”. | Dumitrica (1989) | |
| polar beam/rod/spine (PN) | The straight heavy beam/rod/spine on the top of a cap. A PN is not always connected to a DR. This term includes “a sagittal septum” in the concept of Haeckel (1887, p. 650) | Benson (1966) | |
| pseudo-concentric shell | This term is named for “concentric appearance” of girdles under transmitted light microscope. Although pyloniid skeleton is made of one or more systems of girdles, the skeleton looks like having “concentric” structure. The quick recognition of “pseudo-concentric shell” without regard to the number of a system and the orientation of the central combination is useful in observing mounted slides | New | |
| portal-main spines | Generally, eight long and thin cylindrical radial spines from the edges of girdle, lying in two crossed diagonal planes, opposite direction. | New |
TABLE 2. The definitions of the Type 1 absolute Cartesian coordinate systems for pylonioids.
| Newly defined three coordinate systems | Terms | Sub-terms | Definition | Reference |
| Absolute Cartesian coordinates
(Type 1 coordinates) |
Origin | The center of the microsphere (S1a). This origin is critical when inner pylonioid systems are concerned. | New | |
| Axis | polar axis (Pl-axis) | The axis that crosses the longest orientation of the central combination. | Sugiyama et al. (1992) | |
| lateral axis (Lt-axis) | The axis in parallel to the maximum width of S2a girdle. | Sugiyama et al. (1992) | ||
| sagittal axis (Sg-axis) | The axis which orthogonally crosses both the Pl-axis and Lt-axis. | Sugiyama et al. (1992) | ||
| Plane | polar plane (Pl-plane) | The plane vertical to Pl-axis includes both Sg-axis and Lt-axis. | Sugiyama et al. (1992) | |
| lateral plane (Lt-plane) | The plane vertical to Lt-axis includes Pl-axis and Sg-axis. | Sugiyama et al. (1992) | ||
| sagittal plane (Sg-plane) | The plane vertical to Sg-axis includes both Pl-axis and Lt-axis. | Sugiyama et al. (1992) | ||
| View | polar view (Pl-view) | The view that one can see Pl-plane. | Defined here | |
| lateral view (Lt-view) | The view that one can see Lt-plane. | Defined here | ||
| sagittal view (Sg-view) | The view that one can see Sg-plane. | Defined here |
TABLE 3. The definitions of the Type 2 relative Cartesian coordinate systems for pylonioids.
| Newly defined three coordinate systems | Terms | Sub-terms | Definition | Reference |
| Relative Cartesian coordinates
(Type 2 coordinates) |
Origin | The origin of Type 2 coordinates is virtually defined by the “center” of the outermost pylonioid system. This leads that the origin of type 2 coordinates may or may not be the same with that of type 1 coordinates. This origin is not critical in order to describe something with type 2 coordinates. | New | |
| Axis | Profile axis (Pr-axis) | The axis of the shortest direction of a girdle where one can see a large gate aperture. | Haeckel (1887); redefined here | |
| Upright axis (Ug-axis) | The axis of the widest direction of a girdle where one can see a large gate aperture. | Haeckel (1887); redefined here | ||
| Front axis (Fr-axis) | The axis vertical to both Pr-axis and Ug-axis. | Haeckel (1887); redefined here | ||
| Plane | Front plane (Fr-plane) | The plane vertical to the Fr-axis includes both Ug-axis and Pr-axis. | New | |
| Profile plane (Pr-plane) | The plane vertical to the Pr-axis includes both Ug-axis and Fr-axis. | New | ||
| Upright plane (Ug-plane) | The plane vertical to the Ug-axis includes both Pr-axis and Fr-axis. | New | ||
| View | Front view (Fr-view) | The view that one can see Fr-plane. If the girdle is a ribbon-like girdle, the large aperture of gate is visible. | New | |
| Profile view (Pr-view) | The view that one can see Pr-plane. If the girdle is a ribbon-like girdle, a single tunnel of gate is visible on the same focus of an S1a. | New | ||
| Upright view (Ug-view) | The view that one can see Ug-plane. If the girdle is a ribbon-like girdle, twin tunnels of gate is visible in both sides of the previous system on the same focus of an S1a. | New |
TABLE 4. The counting rules for pylonioids.
| Terms | Definition | Reference |
| Gn [n = 1, 2, 3...] | The distinguishing code of a gate in a pylonioid system (Gn) [n = 1, 2, 3...]: G1, G2, and G3 are coded from the inner gate to outer gate. | Definition herein |
| x ring [x = 1st, 2nd, 3rd...] | The distinguishing code of a ring in a Circodiscus system (x ring) [x = 1st, 2nd, 3rd...]: 1st ring, 2nd ring, and 3rd ring are coded from the inner ring to outer ring. | Definition herein |
| Sn [n = 1, 2, 3...] | The numbering system for the pylonioid system (Sn) [n = 1, 2, 3...]： From the first system, systems are coded as S1, S2, and S3... | Dumitrica (1989) |
| k-girdle [k = a, b, c...] | The distinguishing code of a girdle in a pylonioid system (k-girdle) [k = a, b, c, d...]: a-girdle, b-girdle, c-girdle, and d-girdle are coded from the inner (or early developmental) girdle to outer (or later developmental) girdle in the same system | Dumitrica (1989) |
| Snk girdle | The combination of Sn and k-girdle (Snk girdle): The code Snk-girdle is defined as the k (k = a, b, c...) girdle of Sn (n = 1, 2, 3). For example, the second girdle of the 3rd system is coded as “S3b girdle”. The microsphere is coded as “S1a.” | Dumitrica (1989) |
