The pollination of Habenaria rhodocheila (Orchidaceae) in South China: When butterflies take sides.

Habenaria is one of the largest terrestrial genera in the family Orchidaceae. Most field studies on Habenaria species with greenish-white and nocturnal scented flowers are pollinated by nocturnal hawkmoths and settling moths. However, H. rhodocheila presents reddish flowers lacking a detectable scent and fails to fit the moth pollination syndrome. We investigated the pollinators, breeding system, and functional traits of H. rhodocheila in South China and found that two diurnal swallowtail butterflies Papilio helenus and Papilio nephelus (Papilionidae) were the effective pollinators. When butterflies foraged for nectar in the spur, the pollinia became attached between the palpi. A triangular projected median rostellar lobe was found at the entrance (sinus) of the spur of H. rhodocheila. This lobe divided the spur opening into two entrances forcing butterflies to enter their proboscides through the left or right side. When the projection of median rostellar lobe was removed, the site of pollinium attachment changed to the eyes of the butterflies, leading to a higher rate of pollinium removal but lower rate of pollinium deposition. Our quartz glass cylinder choice experiment suggested that visual rather than olfactory cues provided the major stimuli for butterflies to locate these flowers. Hand pollination experiments suggested this species was self-compatible but pollinator-dependent. However, the proportion of seeds with large embryos produced in self-pollinated fruits was significantly lower than in cross-pollinated fruits, indicating a significant inbreeding depression. Unlike many other orchid species, fruit set was higher than rates of pollinium removal, indicating a high level of pollination efficiency in a species with friable pollinia. Shifts from moth to butterfly pollination in the genus Habenaria parallel other orchid lineages providing insights into the potential for pollinator-mediated floral trait selection.

Calanthe sieboldopsis (Orchidaceae, Epidendroideae, Collabieae), a new species from Luoxiao Mountains, eastern China.

Calanthe sieboldopsis, a new species, is here described and illustrated from Luoxiao Mountains, Jiangxi Province, eastern China. It is morphologically similar to C. sieboldii Decne. ex Regel, but differs from the latter in having smaller flowers, longer spurs, rectangular mid-lobes with emarginate apex (vs. elliptic mid-lobes with mucronate apex), disc with 3 ridges and the proximal ends of the lateral 2 ridges enlarged with light reddish spots and minute white hairs (vs. disc with 5 ridges and 2 rows of white short hairs at base) and pollinia equal in size (vs. unequal in size). A preliminary risk-of-extinction assessment, according to the IUCN Red List Categories and Criteria, is given for the new species.

[Impacts of climate change on the distribution of Cymbidium kanran and the simulation of distribution pattern]. / æ°”å€™å˜åŒ–å¯¹å¯’å °åˆ†å¸ƒçš„å½±å“åŠå ¶åˆ†å¸ƒæ ¼å±€æ¨¡æ‹Ÿ.

In this study, data of 19 climatic factors were downloaded from the World Climate website. A total of 233 Cymbidium kanran distribution data were obtained through online review and field visits. Using MaxEnt model and combined with ArcGIS spatial analysis technology, the potential distribution area and distribution pattern of C. kanran in different periods were simulated, as well as its distribution during the last glacial period and 2070. The results showed that the curve indexes (AUC) value of the model training set was 0.957, and the AUC value of the verification set was 0.953, indicating that the prediction accuracy of the model was very high. The current distribution of C. kanran was mostly affected by the driest quarter precipitation, mean annual precipitation, wettest quarter precipitation, and mean annual temperature range. The contribution rates were 50.3%, 15.9%, 8.4% and 4.4%, respectively, with the total contribution rate being 79.0%. In the last glacial period, C. kanran mainly distributed in Wuyi Mountain, Luojing Mountain, Nanling, Taiwan's five major mountains and some hills in the northern part of Guangxi. From now to 2070, the distribution of C. kanran area will decrease by 22.4%. The southwestern part of Guangxi, the central part of Yunnan, and the junctions of Jiangxi, Fujian and Guangdong provinces will expand, while that in eastern Jiangxi, western Fujian, and the border between these two provinces will shrink.