Araliaephyllum vittenburgii GOLOVN. et VOLYNETS, 2021

Golovneva, Lina, Bugdaeva, Eugenia, Volynets, Elena, Sun, Yuewu & Zolina, Anastasia, 2021, Angiosperm Diversification In The Early Cretaceous Of Primorye, Far East Of Russia, Fossil Imprint 77 (2), pp. 231-255 : 246-247

Araliaephyllum vittenburgii GOLOVN. et VOLYNETS , sp. nov.

Text-fig. 10g 1–2

H o l o t y p e. No. IBSS 41/1a ( Text-fig. 10g 1 ).

P l a n t F o s s i l N a m e s R e g i s t r y N u m b e r:

PFN002696 (for new species).

R e p o s i t o r y. Federal Scientific Center of the East Asia Terrestrial Biodiversity (previously Institute of Botany and Soil Science), Far Eastern Branch, Russian Academy of Sciences, Vladivostok, Russia.

E t y m o l o g y. After geologist P. V. Vittenburg.

T y p e l o c a l i t y a n d a g e. Dachny Creek, Podgorodenka coalfield, Razdolnaya coal basin, Southern Primorye, Russia; Galenki Formation, early-middle Albian.

D i a g n o s i s. Leaves very small, 5–7-lobed, rounded or widely ovate in outline, with cordate base; margin entire; lobes linear-elliptic, with wide rounded apices; central lobe equal in length to upper lateral lobes or slightly shorter; lateral lobes gradually decrease in size towards leaf base; lobe length equal to 1/2 of blade length; sinuses between lobes narrow with rounded apices; basal veins end before lobe apex; lowest basiscopic branches of lateral basal veins strong and innervate 1–2 additional pairs of lateral lobes.

A d d i t i o n a l m a t e r i a l. Specimens IBSS 17/1a and IBSS 17/1b.

D e s c r i p t i o n. Leaves are simple, 5–7-lobed, rounded or widely ovate in outline, with cordate base, 1.4–2.0 cm long, 2.0– 3.6 cm wide. Margin is entire. Lobes are wide, linear-elliptic, with wide rounded apices. The central lobe is equal in length to the upper lateral lobes, or slightly shorter.

The upper lateral lobes are usually the longest and widest. Lateral lobes gradually decrease in size towards the leaf base. The lobe length is equal to 1/2 of the blade length. Sinuses between lobes are narrow, triangular, with rounded apices. The primary venation is palmate, the secondary venation is brochidodromous. Lateral basal veins diverge from the midvein at an angle of 65–75°, strong, slightly curved, ending before the lobe apex. They bear several curved acroscopic and basiscopic branches, which form loops near the margin. The lowest basiscopic branches are stronger, and innervate 1–2 additional pairs of lateral lobes. Tertiary venation is very thin, usually irregular. Higher-order venation is not well preserved.

C o m p a r i s o n. Araliaephyllum luciferum from the Partizansk differs from A. vittenburgii in having a dentate margin and three lobes. A. ussuriense from the Palets Cape also has only three narrow lobes, with the central lobe the largest. Specimens of A. vittenburgii are the most similar to leaves of Araliaephyllum arenarium (G.G.FILIPPOVA) G.G.FILIPPOVA from the Cenomanian Krivorechenskaya Formation of the Anadyr River ( Filippova and Abramova, 1993) in number and arrangement of the lobes, but the lobes of A. arenarium are narrower and longer. In addition, the base of A. arenarium is cuneate, while the base of A. vittenburgii is cordate. The leaves of A. vittenburgii are much smaller.

S t r a t i g r a p h i c h o r i z o n a n d o c c u r r e n c e.

Galenki Formation, early-middle Albian.

Figures

Text-fig. 10. a–d: Araliaephyllum luciferum (KRYSHT.) GOLOVN., Partizansk, Severosuchan Formation, Aptian, a – spec. TSNIGRM 3013/1, lectotype, b – spec TSNIGRM 3013/2, c – spec. TSNIGRM 3013/4, d – spec. TSNIGRM 3013/3; e, j: Pandanites ahnertii (KRYSHT.) GOLOVN., Konstantinovka, Lipovtsy Formation, Aptian, TSNIGRM 3013/5, e – fragment of leaf margin, j – general view, j1 – lectotype, j2 – leaf, figured in (e); f: Araliaephyllum ussuriense (KRASSILOV) GOLOVN., Andreev Inlet, Frentsevka Formation, early-middle Albian, spec. IBBS 28/103; g: Araliaephyllum vittenburgii GOLOVN. et VOLYNETS, Podgorodenka coalfield, Galenki Formation, early-middle Albian, spec. IBBS 41/1, g1 – spec. IBBS 41/1a, holotype, g2 – spec. IBBS 41/1b; h: Dicotylophyllum sp. 1, Podgorodenka coalfield, Lipovtsy Formation, Aptian, spec. IBBS 28L-4; i: Sapindopsis sp., 3rd Kamenka, Frentsevka Formation, early-middle Albian, spec. IBSS 325/8. Scale bar 5 mm in a–h and 1 cm in i, j.

Text-fig. 1. Map of Primorye region, Russia. a – Razdolnaya coal basin; b – Partizansk coal basin.

Text-fig. 2. Map of Partizansk coal basin with early angiosperm localities. a: Severosuchan Formation, Aptian; b: Frentsevka Formation, early-middle Albian. 1 – Novoveselaya village; 2 – 3rd Kamenka River; 3 – Bolshoy Kuvshin; 4 – Andreev Inlet.