PORTULACACEAE 



* Portulaca lutea Solander ex Forster F. (Fig. 19; Pis. 34,38) 



Formerly Known Distribution : Reported 1840 and 1884; 

 L-3233 and 3292, 3231 . 3237, 3255, 3257, from South, 

 Pandanus. Nake. Long, and Emerald, respectively, in open 

 coral, rubble, gravel, and exposed areas, to 1.5 dm high. 



Present Distribution : Range extension from 5 to 33 islets 

 (Table 3). 



Abundance : Along with Heliotropium anomalum is a 

 component of the plant community. Natural Herb Mat (see 

 Plant Communities section). Widespread, predictable on coast 

 and former reef channels but local inland. Covered from one 

 to 60% of land area on almost every transect, windward and 

 leeward, especially facing lagoon. Best areas are Long, Tr. 4 

 (36-m wide meadow); South, north end of Tr. 6 (50 m wide): 

 Brothers, lee, almost pure mat covering 20% ground (6 m 

 wide); Kimoa. north side (8 m wide), 10 cm high; Eitei, north 

 side, 5 cm high. 



Ecology : Primarily occurs along edges of motus in rubble 

 mat and open Tournefortia scrub, averages 12 cm high. 

 Prominent in sparsely vegetated areas, extending seaward to 

 high tide level. Halophytic; highly tolerant of sun. A Hat mat 

 in exposed areas but lusher inland, rising to 2 dm tall. Generally 

 found with Heliotropium, Lepturus, Boerhavia, or Laportea 

 but may form pure mats. Uncommon in Tournefortia scrub 

 patchy in clearings within Pisonia forests up to 13 m high 

 Exceptionally common in old Cocos groves with Boerhavia 

 et cetera (PI. 34); otherwise rare or absent from closed canopy 

 Cocos plantations. Pinker stems found in sunny sites. BIRDS 

 Provides nesting cushion for masked booby, sooty tern, brown 

 noddy. On noddy rock, brown noddies nest on a thick mat of 

 pure Portulaca. Feeding location for shorebirds. 



Phenology: Flowers and fruit October, March, and May. 



Substrata : Coral rubble and gravel, fine to very coarse. 

 Healthier on older sands and coral-humus. 



ZYGOPHYLLACEAE 



* Tribulus cistoides L. (Fig. 1 1 ) 



Formerly Known Distribution : Collected 1884. L-3245in 

 open sandy area among Tournefortia shrubs. Long Island. Not 

 seen elsewhere on atoll. 



Present Distribution : Not seen on our surveys, but present 

 in 2 sites on west-central Long Island. K-90-161 (collected by 

 Anne Falconer), probably from one of same sites as 1965 

 collection. Flowers in March. 



SURIANACEAE 



* Suriana maritima L. (Fig. 20; Pis. 6,21,39,40,44) 



Formerly Known Distribution : Collected 1884. L-3220, 

 shrub to 1.8 m, east edge of Tridacna Islet. 



Present Distribution : K-90-5, 6 from South Island. Range 

 expansion from one to 9 motus (Table 3). 



Abundance : Occasional on Caroline. Forms a vegetation 

 unit. Beach Scrub with Suriana ( see Plant Communities section). 



Phenology : Flowers in March and May. 



Substrata : Best sites in sand but also on coral rubble. 



EUPHORBIACEAE 



# Phyllanthus amarus Schum. and Thonn. (Fig. 1 1 ) 



Formerly Known Distribution : Collected 1884. L-3283, 

 herb Phyllanthus niruri L. (Trelease, 1884) to 4 dm, common 

 on north side of South Island. 



Present Distribution : K-90-10-13, herb, 2 small patches, 

 South Island. Limited to a few square meters in the atoll's only 

 weedy area, less than 10 m : in two small clearings by the 

 recently-renovated cistern. South. A fairly common weed in 

 the Society and Tuamotu Islands, therefore probably arrived 

 with Tahitian copra-cutters and perhaps again within the last 

 2 years. Caroline's only established "weed" (excluding 

 Polynesian introductions such as Cocos). 



MALVACEAE 



o * ( ** ?) (#?) Hibiscus tiliaceus L. (Fig. 1 1 ) 



Never previously collected. K-90-8, 90-9 from South 

 Island, northwest peninsula, in Cocos plantation near old 

 settlement and "landing," in coral rubble and humus, 0.6 m in 

 elevation. 



Present Distribution : Two or three large spreading trees in 

 heavy Cocos shade, 1 m tall, with recumbent branches forming 

 an impenetrable thicket. This species, culturally important to 

 Polynesians, is either indigenous, an early Polynesian 

 introduction, or an ornamental brought by 1 9th century settlers. 



° * (**'?) (#?) Thespesia populnea (L.) Soland. ex Correa 

 (Fig. 1 1 ) 



Never previously collected. K-90-22, 154. 155 from 

 South Island, in Cocos plantation and in lagoon strand, northwest 

 peninsula, near "landing." 



Present Distribution : Two trees ( 10 m tall), one near the 

 cistern, the other in a fringe of native vegetation bordering the 

 lagoon. The history of this species is probably the same as 

 Hibiscus tiliaceus (above). 



* SidafallaxWalp. (Fig. 1 1) 



Formerly Known Distribution : Collected by Dixon, 1884, 

 who found one specimen. 



Present Distribution : Not seen for 106 years. K-90-156, 

 157, 158 from South Island, at edge of cistern, north side. One 

 clump located in a sunny clearing, recently enlarged by the 

 Falconers. 



CONVULVULACEAE 



* Ipomoea macrantha R & S (Fig. 21; Pis. 34,37) 



Ipomoea tuba (Schlecht.) G. Don 

 Formerly Known Distribution : L-3228 and 3293, 3242, 

 325 1 on South, Nake, and Long, respectively. Trailing vines, 

 white flowers, stems to 25 m long climbing over Tournefortia. 

 Morinda. and Cocos. 



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