Systematic significance of seed morphology in the genus Veronica (Plantaginaceae), with special reference to the Egyptian taxa

Abstract

Seed morphology of 29 taxa including 9 subgenera belonging to the genus Veronica was compared using scanning electron microscopy to assess their diagnostic value for systematic studies. Subgenus Beccabunga is the largest in this study represented by nine taxa. Seed surface often varies from ridged reticulate or verrucose/granulate reticulate to rugose-reticulate. Seed color and size have limited taxonomic significance as their variation is uninformative. Thereagainst, seed shape and seed coat ornamentation present informative characters that can be used efficiently in distinguishing the studied taxa. Our seed features support the DNA sequence data in showing close relationships between V. biloba and V. campylopoda, and between V. fruticans and V. fruticulosa. The present study indicates that V. anagallis-aquatica, V. anagalloides, V. comosa, and V. catenata have more or less the same seed features; consequently, these four former species are most likely representing a single species as reported by earlier studies. Furthermore, V. polita and V. persica are very similar in terms of seed characteristics. Our results justify placement of V. peregina within subgenus Beccabunga and support the monophyly of the subgenus Veronica.

Morphological Studies on Seeds of Scrophulariaceae s.l. and Their Systematic Significance

“…lilacina, and V. persica) form an isolated group. Based on the infrageneric classification as done in [47] [32,34]), that seed morphological data can be employed to evaluate the relationships of taxa within the genus and that seed characters can also provide additional support to infrageneric discrimination in Veronica.…”

“…In the past, the variation in seed morphology has been used variously in plant systematics ranging from identification [16,17] and taxonomic circumscription [18,19] to phylogenetic inference [20,21] and character-state evolution [22,23]. Both macro-and micromorphological seed characters have been shown to be of essential systematic importance within and among the genera of traditional Scrophulariaceae, Orobanchaceae, and Plantaginaceae [24][25][26][27][28][29][30][31][32][33][34][35], in which seed morphological characters have been used widely to differentiate the different taxa or to find affinities between them.…”

“…have focused mainly on common genera like Veronica, Scrophularia, and Pedicularis. Juan et al [30] observed fruits and seeds of Scrophulariaceae from southwest Spain, and the systematic significance of seed morphology of Veronica and Pedicularis has been examined in some comprehensive studies [32][33][34]. Despite the aforementioned, no comparative studies on seed anatomy or seed coat characteristics together with surface structure have been conducted on any genera of Scrophulariaceae s.l.…”

Seed coat diversity in some tribes of Cucurbitaceae: implications for taxonomy and species identification

“…Observations of many plant groups have shown that seed morphology and anatomic features are rather conservative, and hence taxonomically important (Barthlott 1981;1984;Werker 1997;Abdel Khalik 2010;Abdel Khalik & Hassan 2012;Hassan & Abdel Khalik 2014).…”

Seed micromorphological study on endemic and subendemic species of <i>Veronica</i> L. (Plantaginaceae Juss.) in Iran

“…V. intercedens is similar to V. capillipes with a cyathiform seed shape, unlike V. viscosa where it is flattened. The seed shape and seed coat of V. rubrifolia are reported to be cyathiform and cristate at dorsal face (Munoz-Centeno et al, 2006;Hassan and Khalik, 2014). In this study, seed shape of V. rubrifolia subsp.…”