Cervantesiaceae Nickrent & Der

Genera included: Acanthosyris (Eichl.) Griseb., Cervantesia Ruiz & Pavon, Jodina Hook. & Arn. ex Meissner, Okoubaka Pellegrin & Normand, Pilgerina Rogers, Nickrent, & Malécot, Pyrularia Michx., Scleropyrum Arnott., Staufferia Rogers, Nickrent, & Malécot,

Habit: Root parasitic trees and shrubs.

Parasitism: Documented for Acanthosyris (Barroso 1968), Okoubaka (Swaine & Hall 1986, Veenendaal et al. 1996), Pyrularia (Leopold and Muller 1983), and Scleropyrum (Rao 1942).

Roots: Haustorium anatomy of Scleropyrum described in Rao (1942).

Stem: young branches glabrous (e.g. Pilgerina) or pubescent.  Acanthosyris and Scleropyrum have ramal and axillary thorns.

Leaves:  Alternate, persistent, petiolate, exstipulate, blade elliptic, lanceolate, or ovate.

Inflorescence: various types such as solitary flowers, monochasia, spikes, racemes, panicles and fascicles. Floral and inflorescence trichomes present. Floral bracts and/or bracteoles persistent or caducous.

Plant Sex:  Variable among the genera, with bisexual flowers (Acanthosyris, Cervantesia, etc.), dioecy (Okoubaka, Staufferia) and trioecy (Scleropyrum).

Flowers: pedicellate or not (flower then sessile). Bisexual or unisexual.

Fruit: Considered pseudodrupes by Bhatnagar and Sabharwal (1969) because they say the stony part of the fruit is derived from the mesocarp, not the endocarp.According to these authors, the endocarp is absent (consumed by the seed endosperm). The exact developmental steps that take place to form the fruits in Cervantesiaceae need to be more clearly documented.  

Fruits in the Pyrularia clade (see Fig. 1 in Rogers et al. 2008) are pseudodrupes with fleshy exocarps. Sometimes the bases of the petals are accrescent. For example, in Pyrularia, these bases become thick and fleshy, forming a ring of 5 "bumps" around the expanded disk at the top of the fruit

In the Cervantesia clade (and possibly to a much lesser extent in Staufferia), fruit morphology is more complex. In Cervantesia and Jodina the five petal bases enlarge basipetally upon fruiting (photo of early stage in Jodina). In the mature fruit these form 5 valves that either remain on the fruit (Cervantesia) or in Jodina they dehisce leaving 5 white, fleshy lobes that surround the nut (stony mesocarp and seed). The white tissue, alternate with the petal valves, appear to be derived from the green nectary disk lobes that alternated with the petals in the mature flower (photo). I'm calling these white tissues accrescent nectary lobes (ANL). This photo shows the petal valves just beginning to dehisce and this photo shows the way the fruit looks without the valves.  The contrasting white ANL and the black expanded disk are apparently attractive to fruit dispersing birds.

Seed: Single per fruit, enclosed within stony mesocarp (thus a pyrene), frequently with taxonomically useful exterior crests, dimples and striations. For example, see Fig. 5 in Halle 1987 (Okoubaka and Scleropyrum) and Fig. 5 in Rogers et al. (2008) for Pilgerina.

Chromosomes: Schnack and Covas (1947) report 2N = 72 for Jodina (as Iodina) rhombifolia.

Alternate Family Names: none

SIUC / College of Science / Parasitic Plant Connection / Cervantesiaceae / Description
URL: http://www.parasiticplants.siu.edu/Cervantesiaceae/description.html
Last updated: 12-Dec-13 / dln