Cycas taitungensis is now C. revoluta.

[scarecrow]

Cycas taitungensis has been lumped into C. revoluta. What will happen with naming all the C. taitungensis in cultivation in the US as they are obviously different plants from the typical commercial C. revoluta? https://www.frontiersin.org/articles/10.3389/fpls.2022.824158/full?fbclid=IwAR2hDHXs_PTMI-U_oKNDiuDddmkJrL44YJJB-SpHGeKBozzl9VhRqOsDbgI

[happypalms]

14 hours ago, scarecrow said:

Cycas taitungensis has been lumped into C. revoluta. What will happen with naming all the C. taitungensis in cultivation in the US as they are obviously different plants from the typical commercial C. revoluta? https://www.frontiersin.org/articles/10.3389/fpls.2022.824158/full?fbclid=IwAR2hDHXs_PTMI-U_oKNDiuDddmkJrL44YJJB-SpHGeKBozzl9VhRqOsDbgI

I found this in an old palms and cycads magazine societies of Australia I found interesting to read

[Tracy]

On 10/19/2023 at 1:06 PM, scarecrow said:

Cycas taitungensis has been lumped into C. revoluta. What will happen with naming all the C. taitungensis in cultivation in the US as they are obviously different plants from the typical commercial C. revoluta? https://www.frontiersin.org/articles/10.3389/fpls.2022.824158/full?fbclid=IwAR2hDHXs_PTMI-U_oKNDiuDddmkJrL44YJJB-SpHGeKBozzl9VhRqOsDbgI

Interesting article and thank you for sharing.  I have a hard time arguing with it though, given that they are doing genetic analysis and using wider sampling than previous studies.  This analysis late in the article sums up there work with less of the science and more layman terms:

Taxonomy Status of Cycas taitungensis: A Synonym of Cycas revoluta

Incomprehensive Morphological Comparisons Misclassify the Interspecific Variation

The leapfrog morphogenetic variations and compatible reproduction under the same coning time indicate interconnected evolutionary fates. Our previous model-based analyses also support high ancestral polymorphism with recent gene flow (Chiang et al., 2009, 2018). Genetic studies have consistently demonstrated the cohesion of the two species, but morphological studies are more complicated, especially regarding species diagnosis and morphological comparisons.

The misidentification of the two species is not only because C. taitungensis had long been misidentified as C. taiwaniana, but also because of the problematic morphological comparisons in the C. taitungensis protolog. The earliest collection of C. taitungensis was made by Shun-ichi Sasaki in 1920. His collection was identified as C. taiwaniana native to the continent (southern China) and classified in sect. Stangerioides until Shen et al. (1994) published C. taitungensis as a new species. However, its morphological comparisons are questionable due to the cited reference (Yamamoto, 1928), which erroneously compared C. revoluta with mixed samples of genuine C. taiwaniana and C. taitungensis. Yamamoto (1928) described that C. taiwaniana has longer leaflets, leaves, and petioles, a smaller revolute margin, a larger insertion angle, and more leaflets. For the reproductive organs, the shape of the male cone is subcylindrical, and the megasporophyll is orbicular to ovate for C. taiwaniana with glabrous ovule (oblong or ovate to lanceolate with tomentose ovule for C. revoluta). However, tomentose ovule is a synapomorphy of sect. Asiorientales (Walters and Osborne, 2004), and Yamamoto’s description suggest that the cited specimens had been misidentified. This also implies that the taxonomic studies (Kanehira, 1936; Li and Keng, 1954, 1975; Liu, 1960) following Yamamoto’s work are questionable (Shen et al., 1994).

After the publication of C. taitungensis (Shen et al., 1994), some questionable examined specimens were still from unknown or erroneous distributions (Chen and Stevenson, 1999; Whitelock, 2002). In addition, due to large morphological variations, insufficient specimen measurements also lead to biased diagnoses. Wang (1996) and Hill (2008) first compared specimens correctly, but their comparison may be biased regionally. They distinguished C. taitungensis from C. revoluta based on (1) longer and flatter non-keeled leaf and non-revolute leaflet, (2) darker and larger seeds, and (3) more tightly, cabbage-like female cones. However, Wang (1996) and Hill (2008) only examined C. revoluta from Fujian and one individual from the northern Ryukyus, respectively (Zheng et al., 2017). The bias also appeared in the seed diagnosis. Whitelock (2002) and Hill (2008) illustrated grooved or non-grooved sclerotesta of C. revoluta and C. taitungensis, contradicting other references that described C. revoluta and C. taitungensis as having a smooth and grooved sclerotesta, respectively (De Laubenfels and Adema, 1998; Chen and Stevenson, 1999). In summary, the aforementioned diagnostic characters were insufficient and did not consider all variations. Our study for a more comprehensive comparison revealed continuous variations in these traits.

[happypalms]

8 hours ago, Tracy said:

Interesting article and thank you for sharing.  I have a hard time arguing with it though, given that they are doing genetic analysis and using wider sampling than previous studies.  This analysis late in the article sums up there work with less of the science and more layman terms:

Taxonomy Status of Cycas taitungensis: A Synonym of Cycas revoluta

Incomprehensive Morphological Comparisons Misclassify the Interspecific Variation

The leapfrog morphogenetic variations and compatible reproduction under the same coning time indicate interconnected evolutionary fates. Our previous model-based analyses also support high ancestral polymorphism with recent gene flow (Chiang et al., 2009, 2018). Genetic studies have consistently demonstrated the cohesion of the two species, but morphological studies are more complicated, especially regarding species diagnosis and morphological comparisons.

The misidentification of the two species is not only because C. taitungensis had long been misidentified as C. taiwaniana, but also because of the problematic morphological comparisons in the C. taitungensis protolog. The earliest collection of C. taitungensis was made by Shun-ichi Sasaki in 1920. His collection was identified as C. taiwaniana native to the continent (southern China) and classified in sect. Stangerioides until Shen et al. (1994) published C. taitungensis as a new species. However, its morphological comparisons are questionable due to the cited reference (Yamamoto, 1928), which erroneously compared C. revoluta with mixed samples of genuine C. taiwaniana and C. taitungensis. Yamamoto (1928) described that C. taiwaniana has longer leaflets, leaves, and petioles, a smaller revolute margin, a larger insertion angle, and more leaflets. For the reproductive organs, the shape of the male cone is subcylindrical, and the megasporophyll is orbicular to ovate for C. taiwaniana with glabrous ovule (oblong or ovate to lanceolate with tomentose ovule for C. revoluta). However, tomentose ovule is a synapomorphy of sect. Asiorientales (Walters and Osborne, 2004), and Yamamoto’s description suggest that the cited specimens had been misidentified. This also implies that the taxonomic studies (Kanehira, 1936; Li and Keng, 1954, 1975; Liu, 1960) following Yamamoto’s work are questionable (Shen et al., 1994).

After the publication of C. taitungensis (Shen et al., 1994), some questionable examined specimens were still from unknown or erroneous distributions (Chen and Stevenson, 1999; Whitelock, 2002). In addition, due to large morphological variations, insufficient specimen measurements also lead to biased diagnoses. Wang (1996) and Hill (2008) first compared specimens correctly, but their comparison may be biased regionally. They distinguished C. taitungensis from C. revoluta based on (1) longer and flatter non-keeled leaf and non-revolute leaflet, (2) darker and larger seeds, and (3) more tightly, cabbage-like female cones. However, Wang (1996) and Hill (2008) only examined C. revoluta from Fujian and one individual from the northern Ryukyus, respectively (Zheng et al., 2017). The bias also appeared in the seed diagnosis. Whitelock (2002) and Hill (2008) illustrated grooved or non-grooved sclerotesta of C. revoluta and C. taitungensis, contradicting other references that described C. revoluta and C. taitungensis as having a smooth and grooved sclerotesta, respectively (De Laubenfels and Adema, 1998; Chen and Stevenson, 1999). In summary, the aforementioned diagnostic characters were insufficient and did not consider all variations. Our study for a more comprehensive comparison revealed continuous variations in these traits.

Interesting read that one all I know is there is a difference in that revoluta in my garden the new fronds get eaten alive by a moth caterpillar and taitungensis is left alone never  touched by the moth caterpillar so much so landscapers are not planting revoluta 

[Merlyn]

So there's two types grown around here that are pretty distinct.  The standard "sago" is everywhere and about 4-6 feet in crown diameter, I guess there's no dispute that these are Revoluta.  The second type is basically a giant Revoluta with flatter fronds (not as deep of a "V" in the leaflets) and 8+ feet in crown diameter.  If I'm reading this right, these giant flat leafed ones are actually Taiwaniana, and were misidentified as Taitungensis?  This would be the same error made in calling plants "Queen Sago" as "Cycas Circinalis" is actually Cycas Thouarsii.  I'm short on available processing cycles in my neural net processor this morning, so I might have things backwards? 

[Scott W]

I'm with Merlyn on this one...interesting read but from my viewpoint of what's growing side by side in my collection they are distinctly different.

Cycas Taitungensis on the left, Revoluta on the right.  Taitungensis was a 4 inch caudex when planted, Revoluta was already trunking, both planted about 15 years ago then transplanted to this location 8 years ago.

 

[Tracy]

22 hours ago, Scott W said:

I'm with Merlyn on this one...interesting read but from my viewpoint of what's growing side by side in my collection they are distinctly different.

If you read through the article, some of the characteristics that you acknowledge make the Cycas taitengensus labeled plants appear different, are exhibited in some of the more isolated communities of  C revoluta.  The fact that the population which has similar traits to C. taitengensus is not the adjacent islands to Taiwan, argues against geographic isolation as being the driver on the traits of the two species.  Ultimately publishing the paper will hopefully allow other scholars to review their procedures and conclusions from the genetic analysis that further lead to their conclusions.  The genetic review was above my level to critique, so I will rely on people more familiar with the field to review and either support or oppose the science.  Ultimately we are seeing the scientific process at work here:  a theory was posed based on knowledge at a given point in time, now we have new data or knowledge being brought to the table, which challenges the old conclusions.   Basing our conclusions merely on our observations of morphological traits that we see when additional information is available is somewhat limiting.

I too have something I got as C taitengensus which appears different than the typical "Sago" Cycas revoluta, but I'm open to listening to the scholars.