The
Scolyminae are treated here in the revised circumscription based on the molecular phylogenetic analyses by Gemeinholzer & al. (in Kilian & al. 2009) and Tremetsberger & al. (2012), comprising four genera with about a dozen species. According to these authors, within the
Scolyminae,
Catananche is sister to the clade including
Hymenonema and
Scolymus, while
Gundelia is sister to all three genera. For the inclusion of
Gundelia see also under
Cichorieae: Systematics: Circumscription of the
Cichorieae.
Usually
Scolymus was treated as an isolated genus without apparent relationship and thus, if formally placed in a subtribe, as the only member of the
Scolyminae (Jeffrey 1966; Bremer 1994; Lack 2006).
Catananche and
Hymenonema, on the other hand, were placed together with
Rothmaleria in a separate subtribe (or informal entity, respectively, by Jeffrey (1966), Bremer (1994) and Lack (2006). As an exception, Blackmore (1981), however, for palynological reasons already associated
Scolymus with
Catananche and
Hymenonema, but also saw
Rothmaleria as a member of this alliance, which he treated as subtribe
Scolyminae. According to the molecular analyses by Gemeinholzer & al. (in Kilian & al. 2009),
Rothmaleria is not related to
Catananche and
Hymenonema but to
Tolpis, as Stebbins (1953) already assumed from morphological data, and therefore placed in subtribe
Cichoriinae.
Morphologically the
Scolyminae appear to be a rather diverse subtribe. They are characterised by an annual to perennial life form, entire to pinnatisect or coarsely lobed, pinnatisect leaves, heads with receptacular scales or bristles, and the pappus being either absent or of scabrid bristles or lanceolate scales. Both
Gundelia and
Scolymus are spiny leafy herbs, the only ones in the entire tribe, with similar pollen morphology and also with sessile heads (or syncalathia, respectively). Moreover, they share the presence of both (functional) oil ducts and latex canals in the roots; functional oil ducts are very rare in the tribe, being otherwise present only in
Scorzonera (see Cichorieae: Systematics).
Gundelia morphologically holds an isolated position because of its heads with non-ligulate but tubular flowers and its much-derived synflorescence, in which one-flowered heads (with much reduced involucres) form a secondary head (syncalathium), of which again a few dozens are aggregated in a second order syncalathium (Classen-Bockhoff & al. 1989).
Scolymus and
Hymenonema share a chromosome number of 2n = 20, while
Gundelia and
Catananche have 2n = 18.
References
Blackmore S. 1981: Palynology and intergeneric relationships in subtribe
Hyoseridinae (
Compositae: Lactuceae). – Bot. J. Linn. Soc. 82: 1-13.
Bremer K. 1994:
Asteraceae. Cladistics and classification. – Portland: Timber.
Classen-Bockhoff R., Froebe H. A. & Langerbeins D. 1989: Die Infloreszenzstruktur von
Gundelia tournefortii L.
(Asteraceae). – Flora 182: 463-479.
Jeffrey C. 1966: Notes in
Compositae I. The
Cichorieae in East Tropical Africa. – Kew Bulletin 18: 427-486.
Kilian N., Gemeinholzer B. & Lack H. W. 2009: Tribe
Cichorieae. – In: Funk V. A., Susanna A., Stuessy T. & Bayer R. (ed.), Systematics, evolution, and biogeography of the
Compositae. – Vienna: IAPT.
Lack H. W. 2006: Tribe
Cichorieae Lam. & DC. – Pp. 180-199 in: Kadereit J. W. & Jeffrey C. (ed.), The families and genera of vascular plants 8. – Berlin: Springer.
Stebbins G. L. 1953: A new classification of the tribe
Cichorieae, family
Compositae. – Madroño 12: 65–81.
Tremetsberger K., Gemeinholzer B., Zetzsche H., Blackmore S., Kilian N. & Talavera S. 2012: Divergence time estimation in
Cichorieae (
Asteraceae) using a fossil-calibrated relaxed molecular clock. – Org. Divers. Evol. 13: 1-13.
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