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AC22 Doc. 10.2 Annex 8f Tridacna maxima Röding, 1798 FAMILY: Tridacnidae COMMON NAMES: Maxima Clam; Small Giant Clam (English) GLOBAL CONSERVATION STATUS: Listed as Lower Risk/Conservation Dependent in the 2004 IUCN Red List of Threatened Species (IUCN, 2004). SIGNIFICANT TRADE REVIEW FOR: Australia, Comoros, Egypt, Fiji, French Polynesia (France), India, Japan, Kenya, Kiribati, Madagascar, Malaysia, Marshall Islands, Mauritius, Mayotte (France), Micronesia, Mozambique, Myanmar, New Caledonia (France), Niue, Palau, Papua New Guinea, Pitcairn Islands (United Kingdom), Réunion (France), Saudi Arabia, Somalia, Sri Lanka, Tonga, United Republic of Tanzania, Vanuatu, Viet Nam, Wallis and Futuna Islands (France) Range States selected for review Range State Exports* Urgent, possible Comments (1994-2003) or least concern Australia 5,386 live Least concern Trade almost entirely in captive-bred specimens. captive Comoros None Least concern No trade reported Egypt Minimal trade Least concern Minimal trade since 1999 since 1999 Federated States 18,679 live Possible concern Population declines in heavily fished areas; high exports of Micronesia wild from wild sources mainly for aquarium trade; domestic use levels unknown; confusion over commercial trade regulations/ban. Fiji ca 28,000 live Possible concern Significant trade in will specimens (though none recorded wild since 2002); domestic use levels unknown; status unknown; no population monitoring or basis for non- detriment findings available. French Polynesia Low trade Least concern Minimal trade India None Least concern No trade reported Japan None Least concern No trade reported Kenya None Least concern No trade reported Kiribati Minimal trade Least concern Minimal trade Madagascar 15,833 shells Possible concern Consistently exported large numbers from wild sources; no wild, 4,343 population monitoring or basis for ensuring non-detrimental live wild nature of exports available Malaysia Minimal trade Least concern Minimal trade Marshall Islands 18,445 live Possible concern Ban on commercial harvest; considerable trade reported as wild, 39,951 imports. live captive Mauritius None Least concern No trade reported Mayotte None Least concern No trade reported Mozambique 167,540 kg Least concern Consistently high trade level until 2001, after which exports wild shells, ceased. Situation should be re-reviewed if trade resumes. 60,860 Myanmar None Least concern No trade reported New Caledonia 7,426 wild Possible concern Shells by-product of considerable domestic market for shells meat; status of stock unknown; no population monitoring or basis for ensuring non-detrimental nature of exports available. Niue None Least concern No trade reported Palau Minimal trade Least concern Minimal trade Papua New 31,000 kg Least concern No exports recorded since 2000 when ban on exports Guinea farmed meat reinstated; unreported trade believed to be occurring Pitcairn Minimal trade Least concern Minimal trade Réunion Minimal trade Least concern Minimal trade AC22 Doc. 10.2 – p. 126 Range State Exports* Urgent, possible Comments (1994-2003) or least concern Saudi Arabia Minimal trade Least concern Minimal trade Somalia Minimal trade Least concern Minimal trade Sri Lanka None Least concern No trade reported Tonga 33,688 live Urgent concern Population overfished in areas; trade in large volumes of wild, 13,113 wild specimens reported as imports every year 1997-2003, live captive despite apparent trade ban on wild exports United Republic Minimal trade Least concern Minimal trade of Tanzania Vanuatu 19,672 live Possible concern Export ban since 2001 substantial exports continue to be wild recorded by Vanuatu: Viet Nam 44,530 live Possible concern Consistently traded in significant quantities from wild wild sources; exports declined in 2003; no information on population monitoring or basis for ensuring non-detrimental nature of exports was available Wallis and None Least concern No trade reported Futuna Islands *Excluding re-exports. SUMMARY Tridacna maxima, the Small Giant Clam, is along with T. squamosa, the most widespread giant clam, occurring from the Red Sea and East African coast across the Indo-Pacific to the Pitcairn Islands in the eastern Pacific. It is considered still reasonably abundant in some range States and is globally classified by IUCN as Lower Risk/Conservation Dependent (IUCN, 2004). The Animals Committee selected 31 countries and territories for the review of significant trade. No trade was recorded from 10 of these for the period under review (Comoros, India, Japan, Kenya, Mauritius, Mayotte, Myanmar, Niue, Sri Lanka, Wallis and Futuna Islands), and they were therefore categorized as of Least Concern and excluded from more detailed analysis. Of the remaining 21, recorded trade in the species during at least the last five years of the period under review was at a low level in ten (Egypt, French Polynesia, Kiribati, Malaysia, Palau, Pitcairn, Réunion, Saudi Arabia, Somalia, United Republic of Tanzania). These were also categorized as of Least Concern. Substantial exports were reported from the remaining 11: Australia, Fiji, the Federated States of Micronesia, Madagascar, the Marshall Islands, Mozambique, New Caledonia, Papua New Guinea, Tonga, Vanuatu and Viet Nam. These were subject to a more detailed review. Australia has traded almost totally in captive-bred specimens over the period so trade from this country is considered of Least Concern. Trade in T. maxima is considered to be of Possible Concern for the Federated States of Micronesia. There are relatively high levels of exports of T. maxima, reported from both wild as well as captive-bred sources, and inconsistencies between national regulations of the Federated States of Micronesia, i.e. prohibition to export giant clams collected in the wild. Reported trade from Fiji in wild-collected specimens remained substantial until 2002. Reported trade in 2003 is limited to farmed specimens. Trade in the species is considered to be of Possible Concern from Fiji pending further information concerning current trade controls for wild specimens. Madagascar has consistently exported large numbers of wild-sourced specimens over the review period. In the absence of any detailed information it is unclear whether non-detriment findings have been made, therefore trade in this species is considered to be of Possible Concern. Trade in T. maxima is of Possible Concern in the Marshall Islands. While the trade in captive- bred specimens may be consistent with the species being bred in mariculture in the Marshall Islands no information was available on this occurring. Five years of trade in wild-sourced specimens appears inconsistent with a ban on commercial harvest. In the absence of information on population monitoring or recent stock status information it is difficult to judge if trade is detrimental to the survival of the species. AC22 Doc. 10.2 – p. 127 Large amounts of T. maxima have been recorded as exported from Mozambique, although none in the last two years of the period under analysis, with the result that trade is at present considered of Least Concern. No information was available on the basis for non-detriment findings; the situation should be re- reviewed should the trade in T. maxima from Mozambique resume. Recorded exports of T. maxima from New Caledonia are higher than those of other Tridacna species. Given high local demand for giant clam products and absence of available information on the status of T. maxima, it is difficult to judge whether adequate information is available to ensure that exports of the species from New Caledonia are sustainable, and therefore trade is of Possible Concern. The ban on exports from Papua New Guinea imposed in 2000 appears to have been successful in stemming trade in T. maxima. There have been no recorded exports since 2000 and the trade in this species is therefore considered of Least Concern. Although Tonga (a non-Party) adopted, in 1993, a ban on export of giant clams unless they are from farmed sources, imports from Tonga reported as from wild sources continue. Trade in large volumes of specimens reported as taken from the wild were reported every year from 1997 to 2003, as were significant quantities of specimens reported at the generic level. For these reasons and Tonga reporting exports at generic levels and with inconsistent units, an Urgent Concern category is considered to apply for the trade from Tonga. Substantial trade in T. maxima from Vanuatu declared as wild-collected has been reported, despite an apparent export ban since 2001. In the absence of population information and basis for ensuring non- detrimental nature of exports available, trade is of Possible Concern. Viet Nam has consistently traded in significant quantities of wild-sourced T. maxima. No information was available on the basis of non-detriment findings, with export of the species from Viet Nam is considered of Possible Concern. Ongoing trade in giant clam species recorded to the family level hinders accurate analysis of the impact of trade on specific species. SPECIES CHARACTERISTICS T. maxima has one of the largest range of all giant clams, occurring in 45 countries extending from the Red Sea and East African coast across the Indo-Pacific to the Pitcairn Islands. Globally, IUCN (2004) classifies the conservation status of T. maxima as Lower Risk/Conservation Dependent. T. gigas reaches a maximum shell size of 40 cm (Table 1). They reach maturity at age two when they are approximately four cm in size. Table 1: Maximum shell length observed and size and age at first year of sexual maturity Species Maximum First year of sexual maturity Remarks Shell Male Hermaphrodite length Age (y.) Size (cm) Age (y.) Size (cm) T. maxima 35-40 2 3.5 2 4.5 Sometimes embedded in corals; widespread species (distribution from the Red Sea to French Polynesia); cultured for aquarium trade (Source: Raymakers et al., 2003) INTERNATIONAL TRADE Over the period 1994-2003, exports of Tridacna maxima were recorded from 31 countries and territories. These included 17 of the 31 countries and territories selected for inclusion in the present review.
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  • List of All Nominal Recent Species Belonging to the Superfamily Mactroidea Distributed in American Waters

    List of All Nominal Recent Species Belonging to the Superfamily Mactroidea Distributed in American Waters

    Appendix A: List of All Nominal Recent Species Belonging to the Superfamily Mactroidea Distributed in American Waters Valid species (in the current combination) Synonym Examined type material Harvella elegans NHMUK 20190673, two syntypes (G.B. Sowerby I, 1825) Harvella pacifica ANSP 51308, syntype Conrad, 1867 Mactra estrellana PRI 21265, holotype Olsson, 1922 M. (Harvella) PRI 2354, holotype sanctiblasii Maury, 1925 Raeta maxima Li, AMNH 268093, lectotype; AMNH 268093a, 1930 paralectotype Harvella elegans PRI 2252, holotype tucilla Olsson, 1932 Mactrellona alata ZMUC-BIV, holotype, articulated specimen; (Spengler, 1802) ZMUC-BIV, paratype, one complete specimen Mactra laevigata ZMUC-BIV 1036, holotype Schumacher, 1817 Mactra carinata MNHN-IM-2000-7038, syntypes Lamarck, 1818 Mactrellona Types not found, based on the figure of the concentrica (Bory de “Tableau of Encyclopedique Methodique…” Saint Vincent, (pl. 251, Fig. 2a, b, pl. 252, Fig. 2c) published in 1827, in Bruguière 1797 without a nomenclatorial act et al. 1791–1827) Mactrellona clisia USNM 271481, holotype (Dall, 1915) Mactrellona exoleta NHMUK 196327, syntype, one complete (Gray, 1837) specimen © Springer Nature Switzerland AG 2019 103 J. H. Signorelli, The Superfamily Mactroidea (Mollusca:Bivalvia) in American Waters, https://doi.org/10.1007/978-3-030-29097-9 104 Appendix A: List of All Nominal Recent Species Belonging to the Superfamily… Valid species (in the current combination) Synonym Examined type material Lutraria ventricosa MCZ 169451, holotype; MCZ 169452, paratype;