Table 1.
Morphological comparison between fossil species of Mesocyparis
| Taxa | M. sinica | M. borealis | M. umbonata | M. beringiana | M. rosanovii |
|---|---|---|---|---|---|
| Seed Cone | |||||
| Length (mm) | 4.4–5.2 | 3.0–5.0 | 2.8–5.0 | 2.0–4.0 | 3.5–5.0 |
| Width (mm) | 4.0–5.1 | 3.0–5.0 | 1.9–4.0 | 2.0–4.0 | 3.0–4.0 |
| Arrangement | opposite | opposite | decussate* | decussate* | most decussate, a few opposite* |
| Cone Scale | |||||
| shape | obovate to ovate | obovate | peltate* | ovate | peltate* |
| Length (mm) | 3.7–4.3 | 3.0–5.0 | 2.3–4.0 | no data | no data |
| Width (mm) | 2.8–3.1 | 3.0 | 1.8–3.9 | no data | no data |
| number | 4 | 4 | 4 | 4 | 4 |
| size of the two pairs | approximately equal in size | approximately equal in size | upper pair larger than lower* | upper pair larger than lower* | approximately equal in size |
| position of umbo on cone scale | near the apex | near the apex | in center* | near the apex | near the apex |
| Shape of umbo’ s tip | acuminate | acute* | acute* | acute* | acute* |
| Shape of umbo | erect | reflexed* | erect | erect | erect |
| Branch | |||||
| Arrangement | opposite, forming flat frond-like sprays | opposite, forming flat frond-like sprays | more than 1/4 alternate, others opposite* | opposite, forming flat frond-like sprays | most opposite, a few alternate* |
| Leaf | |||||
| Facia and lateral leaves of fertile shoots | dimorphic | dimorphic | monomorphic* | dimorphic | monomorphic* |
| Shootlet | |||||
| Length of facial leaves (mm) | 1.1–2.1 | 2.0–3.0 | 0.8–2.0 | 0.5–0.6 | 1.5 |
| Width of facial leaves (mm) | 0.8–1.6 | 1.2–2.0 | 0.6–1.2 | no data | 1.0 |
| Length of lateral leaves (mm) | 0.9–2.4 | 2.0–3.0 | 0.5–2.0 | no data | no data |
| Width of lateral leaves (mm) | 0.4–0.8 | 0.5–1.0 | 0.1–0.4 | no data | no data |
| facial leaves overlap | Present | Present | Present | Absent* | Present |
| lateral leaves overlap | Present | Present | Present | Absent* | Present |
| Shoot | |||||
| Length of facial leaves (mm) | 1.8–3.8 | 3.5–6.0 | 1.4–4.0 | 2.0–3.0 | 1.5–3.0 |
| Width of facial leaves (mm) | 0.4–0.6 | 0.5–1.0 | 0.5–0.9 | 1.5–2.0 | 0.8–2.0 |
| Length of lateral leaves (mm) | 1.7–2.7 | 3.5–5.0 | 1.5–3.8 | no data | 1.5–3.0 |
| Width of lateral leaves (mm) | 0.4–0.5 | 0.5–1.0 | 0.2–0.6 | no data | 0.4–0.8 |
| facial leaves overlapping | Present | no data | Absent* | no data | Absent* |
| facial leaves appressed | Present | Present | Present | no data | Present |
| lateral leaves overlap | Absent | Absent | Absent | no data | Absent |
| apices of lateral leaves free | Present | Present | Present | no data | Present |
| Location | Heilongjiang, China | Saskatchewan, Canada | Alberta, Canada | Koryak, Russia | Amur Region, Russia |
| Age | Early Paleocene | Paleocene | Masstrichtian | Masstrichtian | Early Paleocene |
| Reference | this paper | [18] | [22] | [19, 20, 22] | [21] |
“*” indicating character differences between Mesocyparis sinica and other four Mesocyparis species