Diario de rinaturalist

Hey y'all! I've identified many Atocion armeria observations outside of Europe, but recently I wanted to give Europe and the Middle East a shot and learn more about the rest of the species in Atocion. I've compiled some info here for my own reference and just in case anybody else is interested. Please note that I am not an expert and this is not comprehensive, based on the information that I've found. It's likely that I will tweak some stuff as I see errors.

For an incomplete(?) key and range maps, consult this doc:
https://docs.google.com/document/d/1OTcut7iJGeAPwsHiZm5Cf7mvGVEy6g32U59Wd4WZqZo/edit?usp=sharing

Atocion armeria:

• Sympatric with A. compactum, A. hypanicum, A. lerchenfeldianum, A. lithuanicum, A. rupestre, and A. scythinicinum
• For identification, consult the range map in the doc and compare species.

Atocion compactum:

• Sympatric with A. armeria, A. scythicinum, and A. reuterianum
• Inflorescence densely congested and capitate (versus A. armeria and A. scythicinum with inflorescence lax to slightly congested).
• Flower pedicels 0–2(3) mm long (versus A. armeria and A. scythicinum with flower pedicels 2–15(20) mm long).
• (20–)30–80(−120) cm high (versus A. reuterianum (60–)80–100(−120) cm high).
• Distinct stem internodes (6–)8–12(−14), stems rarely branching in lower portion, sometimes in upper portion, branches not twiggy, without solitary flowers (versus A. reuterianum with distinct stem internodes three to six, stems sometimes branching in lower portion, often in upper portion, branches usually twiggy, often with solitary flowers).
• Bracts subtending the inflorescence 10–30 mm long, (3–)5–15 mm wide (versus A. reuterianum with bracts subtending the inflorescence 4–10 mm long, 2–4 mm wide).
• Petal claw (4.5–)5.0–8.5(−9.0) mm long (versus A. reuterianum with petal claw 8–10 mm long).
• Capsules 6–8 mm long, 2.5–3.5 mm wide (versus A. reuterianum with capsules 8–10 mm long, 4–6 mm wide).
• Found throughout South-eastern and eastern Europe, Turkey, Armenia, Georgia, Iran, Iraq (versus A. reuterianum, restricted to Lebanon).

Atocion hypanicum (possibly synonymous with A. compactum):

• Sympatric with A. armeria and A. lithuanicum
• Inflorescence densely congested and capitate (versus A. armeria and A. lithuanicum with inflorescence lax to slightly congested).
• Flower pedicels 0–2(3) mm long (versus A. armeria and A. lithuanicum with flower pedicels 2–15(20) mm long).
• Restricted to South Bug in Ukraine (versus A. armeria found throughout Europe and A. lithuanicum found in Poland, Lithuania, Ukraine, and Belarus).

Atocion lerchenfeldianum:

• Sympatric with A. armeria
• Stem procumbent, decumbent or ascending (versus A. armeria, growing erect).
• Stem 0.5–1.5 mm wide (versus A. armeria stem 1-10 mm wide).
• Upper portion of the upper internodes not glutinous (versus A. armeria, with upper portion of the upper internodes glutinous).
• Anthophore (3.0–)4.0–6.5(−7.5) mm long (versus A. armeria with anthophore (6–)7–9(−10) mm long).
• Calyx cylindrical–clavate, (6.5–)7.0–11.0(−12.0) mm long (versus A. armeria with calyx long and tubular, (11–)12–17(−18) mm long).
• Petal limb entire, rarely slightly emarginated (versus A. armeria with emarginate petal limb).

Atocion lithuanicum (possibly synonymous with A. armeria):

• Sympatric with A. armeria and A. hypanicum
• Narrower stem leaves with abaxially folded margins (versus A. armeria with wider stem leaves and margins not folded abaxially).
• Slightly longer carpophores and capsules (versus A. armeria with slightly shorter carpophores and capsules).
• Petals with a less distinguished notch (versus A. armeria with noticeable emarginate petals).
• Smaller seeds without papillae (versus A. armeria with larger seeds with papillae).
• Inflorescence lax to slightly congested (versus A. hypanicum, inflorescence densely congested and capitate).
• Flower pedicels 2–15(20) mm long (versus A. hypanicum with flower pedicels 0–2(3) mm long).
• Found in Poland, Lithuania, Ukraine, and Belarus (versus A. hypanicum, restricted to South Bug in Ukraine).

Atocion reuterianum:

• Sympatric with A. compactum
• (60–)80–100(−120) cm high (versus A. compactum, (20–)30–80(−120) cm high).
• Distinct stem internodes three to six, stems sometimes branching in lower portion, often in upper portion, branches usually twiggy, often with solitary flowers (versus A. compactum with distinct stem internodes (6–)8–12(−14), stems rarely branching in lower portion, sometimes in upper portion, branches not twiggy, without solitary flowers).
• Bracts subtending the inflorescence 4–10 mm long, 2–4 mm wide (versus A. compactum with bracts subtending the inflorescence 10–30 mm long, (3–)5–15 mm wide).
• Petal claw 8–10 mm long (versus A. compactum with petal claw (4.5–)5.0–8.5(−9.0) mm long).

• Capsules 8–10 mm long, 4–6 mm wide (versus A. compactum with capsules 6–8 mm long, 2.5–3.5 mm
  wide).

• Restricted to Lebanon (versus A. compactum, found throughout South-eastern and eastern Europe, Turkey, Armenia, Georgia, Iran, Iraq).

Atocion rupestre:

• Sympatric with A. armeria
• Anthophore 0.6–1.5 mm long (versus A. armeria with anthophore (6–)7–9(−10) mm long).
• Petals white, rarely pink (versus A. armeria with petals pink, rarely white).
• Calyx campanulate, 3.5–5.5 mm long (versus A. armeria with calyx long and tubular, (11–)12–17(−18) mm long).
• Upper portion of the upper internodes not glutinous (versus A. armeria, with upper portion of the upper internodes glutinous).

Atocion scythicinum:

• Sympatric with A. armeria and A. compactum
• Anthophore 5–7 mm long (versus A. armeria with anthophore (6–)7–9(−10) mm long).
• Calyx 10–12 mm long (versus A. armeria with calyx (11–)12–17(−18) mm long).
• Basal leaves are persistent (versus A. armeria with basal leaves soon withering).
• Restricted to Rize, Turkey (versus A. armeria spread throughout Europe, north-eastern Anatolia, and the rest of the world, and A. compactum found in South-eastern and eastern Europe, Turkey, Armenia, Georgia, Iran, Iraq).
• Inflorescence lax to slightly congested (versus A. compactum, inflorescence densely congested and capitate).
• Flower pedicels 2–15(20) mm long (versus A. compactum with flower pedicels 0–2(3) mm long).

References:
Martynyuk, Viktoria & Karpenko, Nataliia & Tarieiev, Andrii & Kostikov, Igor. (2018). Differences of Atocion lithuanicum from A. armeria (Sileneae, Caryophyllaceae) and their hybrid by ITS1-ITS2 sequences and secondary structure of their transcripts. Ukraïnsʹkyĭ botanichnyĭ z︠h︡urnal. 75. 322-334. 10.15407/ukrbotj75.04.322.

Frajman, Božo & Thollesson, Mikael & Oxelman, Bengt. (2013). Taxonomic revision of Atocion and Viscaria (Sileneae, Caryophyllaceae). Botanical Journal of the Linnean Society. 173. 10.1111/boj.12090.

Martynyuk, Viktoria & Tyshchenko, Oksana & Karpenko, Nataliia & Tarieiev, Andrii & Kostikov, Igor. (2014). Taxonomic status of Atocion hypanicum (Klokov) Tzvelev (Caryophyllaceae) inferred from analysis of ITS1 and ITS2 secondary structure. Chornomorski Botanical Journal. 10. 416-425. 10.14255/2308-9628/14.104/1.

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