Invasion History
First Galapagos Record: 2005General Invasion History:
Nemalecium lighti was described from Mindoro, Philippines, in 1924. In the Indo-West Pacific, it is also known from Reunion and Guam (Kirkendale and Calder 2003). It was first recorded from the Western Atlantic at Twin Cays, Belize in 1987, and is known from southwest Florida to Brazil. Its status as an introduced species in the Atlantic is unclear (Calder 2019). Its first record in the East Pacific, in the Galapagos Islands in 2005, and in Ecuador in 2018, are more clearly introductions (Calder et al. 2019; Calder et al. 2021).
Invasion History in the Galapagos:
Nemalecium lighti was first observed in the Galapagos off Isla Wolf Isla Marchena, and Isla Darwin by Banks in 2005 (Banks et al., 2009). In 2015–2016, it was collected in Puerto Ayora, and Franklins Bay on Isla Santa Cruz, (Calder et al. 2019).
Invasion history elsewhere in the world:
Invasion history for Elsewhere in the World has not been summarized for this species at this time.
Description
The hydrozoan Nemalecium lighti forms colonies of monosiphonic and polysiphonic stalks with transverse nodes and irregular branching nodes (branching in opposite directions). Each branch has a primary hydrotheca, with branches developing below, with secondary hydrothecae developing on pedicels. The hydrothecae are small and conical, but male gonothecae form elongated cones. A unique feature of the genus is the presence of nematodactyls, fingerlike defensive structures, with large, elongated nematocysts that occur with the tentacular whorls on the hydroids and curve over the rim of the hydrothecae. Colonies reach up to 54mm tall (Migotto 1996; Calder 2019; Calder et al. 2019).
Nemalecium lighti lacks true medusa, but the gonangia release short-lived non-feeding medusoids, which release eggs and sperm (Gravier-Bonnet et al. 2000).
Taxonomy
Taxonomic Tree
| Kingdom: | Animalia | |
| Phylum: | Cnidaria | |
| Class: | Hydrozoa | |
| Family: | Haleciidae | |
| Genus: | Nemalecium | |
| Species: | lighti |
Synonyms
Potentially Misidentified Species
Similar species, described from the Caribbean (Galea et al. 2012)
Ecology
General:
Nemalecium lighti is an asexually reproducing hydroid, which produce sexual gonangia that release briefly planktonic medusoids. Lacking tentacles, the medusoids survive about two hours, releasing eggs and sperm which develop into planulae (Gravier-Bonnet 2000 and Migotto 1996).
Food:
Invertebrates larvae, zooplankton, diatoms
Trophic Status:
Suspension Feeder
SusFedHabitats
| General Habitat | Coral reef | None |
| General Habitat | Marinas & Docks | None |
| General Habitat | Mangroves | None |
| Salinity Range | Polyhaline | 18-30 PSU |
| Salinity Range | Euhaline | 30-40 PSU |
| Tidal Range | Subtidal | None |
| Vertical Habitat | Epibenthic | None |
Life History
Tolerances and Life History Parameters
| Minimum Height (mm) | 18 | Galapagos, Calder et al. 2021 |
| Broad Temperature Range | None | Subtropical; Tropical |
| Broad Salinity Range | None | Polyhline-Euhaline |
General Impacts
There is one case of a diver being stung by the hydroid of Nemalecium lighti in Brazil (Marques et al. 2002). Impacts in the Galapagos are not known.
Regional Distribution Map
| Bioregion | Region Name | Year | Invasion Status | Population Status |
|---|---|---|---|---|
| SEP-Z | 2005 | Def | Estab |
Occurrence Map
| OCC_ID | Author | Year | Date | Locality | Status | Latitude | Longitude |
|---|
References
Banks, Stuart; Vera, Mariana; Chiriboga, Angel (2021) Establishing reference points to assess long-term change in zooxanthellate coral communities of the northern Galapagos coral reefs, Galapagos Research 66: 43-64Calder, Dale R. (1993) Local distribution and biogeography of the hydroids (Cnidaria) of Bermuda, Caribbean Journal of Science 29(1-2): 61-74
Calder, Dale R. (2010) Some anthoathecate hydroids and limnopolyps (Cnidaria, Hydrozoa) from the Hawaiian archipelago, Zootaxa 2590: 1-91
Calder, Dale R. (2019) On a collection of hydroids (Cnidaria, Hydrozoa) from the southwest coast of Florida, USA, Zootaxa 4689(1): 1-141
Calder, Dale R. and 8 authors (2021) Additions to the hydroids (Cnidaria, Hydrozoa) of marine fouling communities on the mainland of Ecuador and in the Galapagos Islands, Aquatic Invasions 16: 208-252
Calder, Dale R.; Carlton, James T.; Larson, Kristen; Mallinson, Jenny J.; Choong, Henry H. C.; Keith, Inti; Ruiz, Gregory M. (2019) Hydroids (Cnidaria, Hydrozoa) from marine fouling assemblages in the Galápagos Islands, Ecuador, Aquatic Invaders 14: 21-58
Calder, Dale; Faucci, Ansuschka (2021) Shallow water hydroids (Cnidaria, Hydrozoa) from the 2002 NOWRAMP cruise to the Northwestern Hawaiian Islands, Zootaxa 5085(1): 1-73
https://doi.org/10.11646/zootaxa.5085.1.1
Coma, R.; Ribes, M.; Orejas, C. ; Gili, J.-M. (1999) Prey capture by a benthic coral reef hydrozoan, Coral Reefs 18: 141}145
Galea, Horia R.; Ferry, Romain Bertot, Jean-Marie (2012) Medusoids in the life cycle of Dentitheca dendritica (Nutting, 1900) and Nemalecium gracile sp. nov. (Cnidaria: Hydrozoa), Zootaxa 3527: 43-54
Gravier-Bonnet, Nicole; Migotto, Alvaro E. (2000) Gonangium development and medusoid of Nemalecium lighti (Hargitt, 1924) (Cnidaria: Hydrozoa, Haleciidae), Scientia Marina 64(Suppl. 1): 207-213
Kirkendale, Lisa; Calder, Dale R. (2003) Hydroids (Cnidaria: Hydrozoa) from Guam and the Commonwealth of the Northern Marianas Islands (CNMI), Micronesica 35-36: 159-188
Migotto, A.E. (1996) Benthic shallow-water hydroids (Cnidaria, Hydrozoa) of the coast of Sao Sebastiao, Brazil, including a checklist of Brazilian hydroids, Zoologische Verhandelingen 306: 3-125
Oliveira, Otto M. P. and 24 authors (2016) Census of Cnidaria (Medusozoa) and Ctenophora from South American marine waters, Zootaxa 4194: 1-256