Chapter 9 Fishes
Introduction to the Freshwater Fishes
J. S. Sparks and M. L. J. .Stiassny
Alrhough many of Madagascar's rcrrestrial vertebrares have knowledge persist. Finally, in the face of the current rate of been studied in great decail, parricularly the lemurs, very aquatic habitat degradation in M·adagascar, we present our little up-to-date information is availa ble for the highly vicw of the future of the island's freshwater ichthyofauna. threatened freshwater fishes native to the island. This intro In many ways Madagascar possesses a typical island duction provides a summary of Madagascar's native fresh ichthyofauna, but it is also one that differs in certain re water fishes and an update on the current state of knowl spects because of its continemal (Gondwanan) origin. Like edgc regarding the origins, composition, biogeography, those of many true oceanic islands, Madagascar's na and relationships of this ali but neglected vertebratc buna. tive ichthyofauna is relatively depauperate at broad taxo We do not attempt a summary of the hydrology, limnology, nomie levels when compared with those of much larger, or conservation status of Madagascar's aquaric resources geogmphically more diverse continentallandmasses (table here, as these have bcen presented in detail elsewhere 9.1). However, bascd on the revised totals presented herein (e.g., Battistini and Richard-Vindard 1972; Chaperon et al. and considering the surface arca of the island, the notion of 1993; Riseng 1997; Wright 1997; Benstead et al. 2000). a depauperate ichthyofauna at the species leve! for Mada Herein wc focus on patterns of fish diversity and distribu gascar is no longer tenable (e.g., Kiener 1963; Kiener and tion and the historical geological events that have shaped Richard-Vindard 1972; Jenkins 1987). In fact, Madagas them. car's freshwarer fish fauna is shown to be numerically fully To interpret the origin(s) and current composition of the in line with those of other landmasses of similar size and ichthyofauna in a useful way, we need not only information supports more or Jess cxacdy as many species as would be on the phylogenetic affinities of the groups present but also predicted given the island's surface area of nearly 600,000 knowledge of their distributions in space and ti me. We sum km2 (fig. 9.1; MacArthur and Wilson 1967; Brown and marize both historical and recent survey data and attempt Lomolino 1998). to synthesize these and current phylogenetic hypotheses in In contrast to many othee island systems and owing ro order to provide a contextual overview of the island's fresh its continental origin, Madagascar, isolated since. the Creta water fish faur}a. Comrary to a commonly expressed belief ceous (Storey 1995; Hay et al. 1999), is home to small radi (e.g., Grandidier and Petit 1932), Madagascar's freshwater ations of freshwater fishes thar do not readily enter marine fishes are not well known, and phylogenetic relationships of habitats. Many taxonomie groups with members present only a few groups have been investigated to date. We docu on the island have broad Gondwanan distributions and ment this low leve! of knowledge and discuss possible rea rhus rich potential to provide insighr into the past connec sons for it, as weil as how our understanding of this fauna tions of the southern continents. In sharp contrast, othee has advanced over the past decade and where gaps in islands of the region, such as the Comoro Islands and
849 850 Fishes Introduction
10000 w 1965; Kiener and Maugé 1966; Kiener and Richard Vindard 1972), and by the carly part of the past cenrury most biologists had concluded chat the ichthyofauna of Madagascar was weil known (e.g., Grandidier and Petit 1000 IS ... 1932). However, beyond lists of species known at the time, 1 10 .. for the most part little additional information on the is a:l land's fishes was reported in this literature. Notably lacking
100 was information on !ife history, reproductive biology, and t"' $1. cu Il relationships of the native fishes and their patterns of dis ! NZ MDl tribution both within Madagascar and regionally. ln fact, despite a literature going back 150 years, it is remarkable 10 how little we still know about the majority of Madagascar's .. freshwater fishes . Perhaps as a result of this lack of knowledge, Madagas
10' 10' ,,. 10' ,,. car's fishes have not been a mainstream focus for efforts of At•• (km') conservation organizations or government agencies, and in the design of protected areas native fishes have traditionally Figure 9. 1. Species-area relatiooships for the reported number of native fresh water fish species from MadagaS(ar and ether continental and oceanic land been neglected. Furthermore, larger rivees are frequently masses (modified alter Riseng 1997). Relationships are shown indicating the in used as reserve boundaries, which does little to prorect the crease in the number of freshwater fish species recorded from the fresh waters of integrity of the river itself. An exemplary exception is the Madagascar over the past three decades (symbols MO 1-MD4). Totals for Mada gascar are shown correspondin<) to the number of native freshwater species re recendy designated Parc National (PN) de Masoala in ported in this study (MD• •: 143 spp.); the number of endemie freshwater spedes northeastern Madagascar (Kremen et al. 1999). The PN de recorded in this study (MOe: 93 spp.); and the number of endemie species re corded by Kiener and Maugé {1972, MOt: 32 spp.), Stiassny and Raminosoa Masoala was designed to indude river basins within its bor (1994, M02: 42 spp.), de Rham (1996, M03: 49 spp.). and Benstead et al. (2000, ders specifically to protect native fish communities. Possibly M04: 58 spp.). Abbreviations (references for species tetais used to compile this another reason for a continued terres trial bias is the sad fact figure Jisted in parentheses): Af = Alrica (Caget et al. 1984, 1986; Skelton 1990; lundberg et al. 2000); AS .. Australia (Allen 1989; Pellard et al. 1990; McOowall that today few areas of the island remain where intact na 1996); B = Bornee (M. Kottelat (pers. comm.l records 394 species from Bornee tive fish communities persist. Exotic species, especially eila· (shown] and estimates that there are now approximately 450 described species (not shownJ; Inger and Kong(1962] report 290 species from western Bornee (not piine cichlids introduced for aquaculture purposes, are shownD; CU-= Cuba (SS(shownl recorded by Alayo (19731 and 36(not shawn} ubiquitous in ali but the most remote regions of the island by Vergara (1980}); Hl = Hawaii (Fitzsimons and Nishimoto 1990); lM = Inde (j. Sparks and K. Riseng unpubl. data), and the degree of Malay archipelago (Zakaria-lsmail 1994 (minimum estimateJ; Kottelat {19981 states that approximately 1000 species are known from western lndonesia (not habitat degradation and destruction in Madagascar has shawn )); IS = lndian subcontinent (Ta lwar and Jhingran 1992); NA= North Amer been, and continues to be, severe (Benstead et al. 2000). ica (Williams and Miller 1990; lundberg et al. 2000); NG = New Guinea (Munro The paucity of information on Madagascar's freshwater 1967; Allen [ 1991 J records 320-350 species including sorne estuarine forms (not shownlJ; NZ =New Zealand (McOowall 1990); SA ~ South America (Moyle and fishes, and the Jack of consideration they have received from Cech 1996; Vari and Malabarba 1998); SL =Sri Lanka (Pethiyagoda 1991); and conservationists, are certainly also attributable to the inac w = wocld (Stiassny 1996; Lundberg et al. 2000). Geographie areas obtained from Rand McNally Universal World Atlas (1987).• cessibility of many of the island's river basins and the dif ficulties associated with the conservation of river systems in general (Boon et al. 2000). Most of Madagascar's protected Mascarenes (which are of recent volcanic origin, 15 million areas are very small, frequenrly consisting only of a small years ago [Ma] or less) and the granitic Seychelles (ancient forest fragment surrounded by an expansive deforested re Gondwanan fragments isolated since approximately the gion. Under such circumstances, at very best only a few Late Cretaceous [Plummer and Belle 1995; Storey 1995]), headwater streams can be afforded any protection. Unfor have extremely depauperate fish faunas dominated by ma tunately, headwater regions do not harbor diverse fish as rine colonizers or species with !ife histories dependent semblages and as such are not the habitats most în need of on marine habitats, such as gobies, eleotrids, ambassids, protection from the perspective of maintaining ichthyolog eels, and mullets (Bennett 1830; Bleeker and Pollen 1875; ical diversity. Teugels et al. 1985). lt has long been recognized that Madagasca r is charac An extensive literature on Madagascar's freshwater terized by a highly endemie freshwater ichthyofauna, but fishes datesfrom the mid-1800s (e.g., Bleeker 1868; Bleeker historically this fauna has been viewed as notably species and Pollen 1875; Sauvage 1891; Grandidier and Petit 1932; poor. Calculations based on prior estimates of species rich Pellegrin 1933; Bertin 1948; Arnoult 1959; Kiener 1963, ness suggested that Madagascar was home to only about J. S. Sparks and M. l. J. Stiassny 851
Table 9. 1. Checklist of native Malagasy freshwater flshes and their regions of occurrence
Conservation Southern Western Northwestern Eastern Eastern Taxon status basins basins basins highlands lowlands Anguillidae Anguilla bicolor s x x x x x A. marmorata s x x x x x A. mossambka s x x x x x Clupeidae Pellona ditche!a u x x x Sauvage/fa madagascariensis s x x x S. nov. sp. *robustaH u x Spratellomorpha bianafis u x x Ariidae Arius afrkanus s x x x A. dussumieri u x x A. madagascarlensis T x x A. nov. sp. *ankofia* T x A. nov. sp. *sofia• u x Anchariidae Ancharlus brevibarbus TIR x x A. fuscus T/R x x A. nov. sp. ·southwestH R x A. nov. sp. *southeast * R x Atherinidae Atherinomoros d . duodecimalis s x x x Teramulus klenerl R/E? x T. waterloti R x Bedotiidae Sedotia geay/ T x B. madagascariensis T x B. /ongianalis T x B. marojejy T x B.masoala T x B. tricolor T x B.vondrozo T x B. nov. sp. "bemarivo .. T x B. nov. sp. *betampona* T x x B. nov. sp. *garassa • T B. nov. sp. */azana• T x B. nov. sp. *mahanara• T x B. nov. sp. *manomboH T/R x B. nov. sp. *marosivy• T x x B. nov. sp. *nosivoloH T x B. nov. sp. *ranomafana• T x B. nov. sp. *sambava" T Rheocles a/aotrensis T x R. derhami u x R. larera/is T x R. pellegrini R) x R. sikorae E? x R. wrightae RIE' x R. nov. sp. *ambatovy• TIR x R. nov. sp. *andapaH u x R. nov. sp. *rlanfla• u x (continuee/) 852 Fishes Introduction
Table 9.1. (cootinued)
Conservation Southern Western Northwestern Eastern Eastern Taxon status basins basins basins highlands lowlands Aplocheilidae Pachypanchax sakaramyi T x P. omalonotus T x P. nov. sp. •anjingo• T x P. nov. sp. •betslboka• T x P. nov. sp. •manambery• T P. nov. sp. •sofia• TIR x Poec~iidae Pantanodon madagascariensis x P. nov. sp. •manombo• RIE? x Syngnathidae Coelonotus leiaspis u x x x Hippichthys cyanospilus u x x x MICJOPhis brachyurus s x M. fluviatilis s x x x Ambassidae Ambassis fontoynonti T A natalensis s x x x x A. productus s - x x x x Terapontidae Terapon jarbua s x x x Mesopristes elongatus u x x Kuhliidae Kuhlia rupestris s x x x x Monodactytidae Monodactylus argenteus s x x x Scatophagidae Scatophagus tetracanthus s x x x Carangidae Caranx sexfasciatus s x x x Chanidae Chanos chanos u x x x Ci chlidae Paratilapla pol/eni T x x x x P. bleekeri T x x x P. nov. sp. •al/ black• R x P. nov. sp. •fony• T x P. nov. sp. •;hotry• E? x Ptychochromis grandidieri s x P. oligacanthus T x x x x P. nov. sp. •btack saroy• u P. nov. sp. •green garaka• u x x P. nov. sp. •fnornatus• R x x P. nov. sp. •kotrolonili•hy• E? x P. nov. sp. •mipentina• u x P. nov. sp. •nossibeensis• T x x Ptychochromoides betsileanus R x P. katria R x P. vondrozo R x P. nov. sp. •jtasy" x Oxylapia po/li R x Paretroplus damii T x P. kieneri T/R x x P. maculatus TIR x P. maromandia R x x P. menarambo R/E1 x P. nourissati T x J. S. Sparks and M. L. J. Stiassny 853
T.,ble 9.1. (continued) Conservation Southern Western Northwestern Eastern Eastern Taxon status basins basins basins highlands lowlands P. petit/ R? x P.polyadlr s x x P. nov. sp. •anlcarafantslkèf• T x x P. nov. sp. ·dambabe• T x P. nov. sp. •dridrimena• T x P. nov. sp. •tac parinadrina• T x P. nov. sp. •sofia• T/R x P. nov. sp. •tsimoty• T x P. nov. sp. •ventitry• T Mugilidae Agonostomus telfairii T x Uza rnacrolepis u x x x L. alata u x x x Mugit cephalus u x x Valamugil buchanani u x x x V. tobustus u x x Gobiidae Acenuogobius audax u x x x A therezieni u x Awaous aeneofuscus s x x x Chonophorus macrorhynchu$ u x x Glossogobius bioceRiJtus u x x G. giuris s x x x x G. ankaranensis T x x G. callidus u x x Gobius hypselosoma u x x &uhygobius sambiranoensis u x B. fuscus u x tstigobius omiJtuS u x x x 0/igotepis iJCutipennis u Oxyurichthys tentaculatis u x x x Popif/ogobius reichei u x x x Redigobius balteiltops u x R. bikofilnus · u x Sicyopterus laticeps T x x S. franouxi T x x S. nov. sp. •masoala• T x x Stenogobius genivittatus u x x x Taenioides gracilis u x Yongeichthys nebulosus u x x x Eleotridae Butis butis s x x x Eleotris acanthopoma u x f . fusca 5 x x x x E. melanosoma u x x E. pel/egrini u x x E. vomerodentata u x Hypse/eotris tohizonae u x x (continued) 854 Fishes Introduction
Table 9.1. Ccom.nued)
Conservation Southern Western Northwestern Eastern Eastern Taxon status basins basins basins highlands lowlands Ophiocara porocl!phala u x x x O. macrol!!pidora u x x Ratslrakia J~gendrei T x x Typhleotris madagascariensis R x T. pauliani R x T. nov. sp. ~anomafy" R x Megalopidae Megalops cyprinoides s x x Totals' 10 49 71 51 69 .
NOTES: The live major ecoregions listed correspond tc those discussed in the te~t. Families. genera, or species in boldface typl! are endemie tc Madagascar. Conse..Va tion status abbreviations: S. se 30% of its predicted freshwarer fish diversity, based on a water habitats remain throughout Madagascar that are not surface area of nearly 600,000 km! (Riseng 1997). In con highly disturbed, degraded, and dominated hy exotic spe trasr, the summary presented here brings Malagasy fresh cies (fig. 9.2). water fish species diversity completely into line with those ?\·tost summary works on Malagasy freshwater fishes are of other land masses of comparable size (fig. 9 .1, table 9.1 ). now outdated (e.g., Blcekcr and Pollen 1875; Sauvage Whereas our new findings are satisfying from a rheoretical 1891; Pellcgrin 1933; Arnoult 1959; Kiener 1963; Kiencr standpoint, they are disheanening from one of conserva and Richard-Vindard 1972; Stiassny and Raminosoa 1994; tion. The combined pressures of human encroachmenr, de de Rham 1996) or self-admittedly incomplete and cursory forestation, overfishing, and the introduction of a wide va (jcnkins 1987; Glaw and Vences 1994 ). Most edited com riety of exotic species are having a major impact on native pilations dealing with "cntire" Malagasy faunas have failed fish populations (Stiassny and Raminosoa 1994; Benstead to include consideration of fishes or aquatic systems in gen et al. 2000). Numerous species, including a number of un eral. Happily, there are recent indications of change (see, described taxa, are recognized as extremely endangered e.g., Goodman 2000; part 9 of this volume), and as an en or verging on extinction or both (table 9.1; Harrison and couragement to such inclusion we fee! it timely to reevalu Stiassny 1999; Benstead et al. 2000). Although infrequently ate the starus of Madagascar's freshwater fishes. The results discussed in the conservation literature, many of Madagas presented in this chapter represent a decade of surveys car's endemie freshwatcr fishes likely represent sorne of the conductcd across the island, as well as revisional works on most, if not the most, endangered vertebrates on the island a numbcr of fish groups. Many colleagues have graciously (Sriassny and Raminosoa 1994; Wright 1997; Sparks and made their specimens and collection data available to us, Stiassny in press). and we have attempted to incorporate as much information Globally, freshwater systems are often overlooked in the as possible into this summary. preparation of conservation protocols, and Madagascar has been no exception to this bias. This is a remarkable oversight when one considers thar freshwater fishes alone Species lnventory account for an astounding 20-25% of the world's verte brate dh·ersity (Stiassny and Raminosoa 1994; Lundberg We have fairly comprehensive survey coverage of the island, et al. 2000). Few pa pers have dealt specifically with the con· less a few critical regions in dire need of exploration (fig. servation of Madagascar's freshwater fishes (e.g., Reinthal 9.3A: shaded regions). In particular, we Jack data for west and Stiassny 1991_; Stiassny and Raminosoa 1994; Sparks ern Madagascar to the south and west of the Mahavavy and Stiassny in press), yet the entire Malagasy freshwater du Sud Basin, the remote forested regions of the eastern ichthyofauna, and aquatic systems of the island in general and western highlands extending from Mandritsara south (Riseng 1997), are in serious trouble. Extremely few fresh- to Lac Alaotra (including headwaters of both eastern and Figur~ 9.2. Pristlne and moderately disturbed freshwater hab1· tats: (A) A pristine rain forest stream in northeastern Madagascar (Ankavanana River, Masoala Peninsula). (B) A moderately dis· turbed river in northwestern Madagascar (Anjingo River. Ankofia drainage, near Antsohihy). (C) A typical highly disturbed lacus trine freshwater habitat in north~.WStern Madagascar (Lac Rave lobe near the Station forestière d'Ampijoroa) thal has been con verted for rice cultivation and grazing of livestock. (0) A highly disturbed riverine habitat in the central highlands. upper Man goro drainage east of Antananarivo. 856 Fishes Introduction renee. This approach has resulted in the elimination from table 9.1 of certain species historically reported to occur in A Madagascar, such as Sicyopterus lagocephalus, S. (1.1sciatus, and Kuhlia caudivittata, for which we were unable to ver ify a record of occurrence on che island. The attribution of rhese species, and certain others, to Malagasy inland waters is the result of either taxonomie misidentification or incor rectly reported locality data. Given that Madagascar's fresh water fishes have traditionally been poorly studied, many unique endemie species have erroneously been anributed ro nominal species that do noe occur anywhere within che Mascarene region (also induding the Comoro Islands, the islands of La Réunion, Mauritius, and Rodrigues, and the Seychelles Islands). Further, wc have rectified severa! taxonomic/species misidenrifications thar had persisted in the literature. Table 9.1 includes a number of undescribed species, ali of which we have examined ro confirm their taxonomie sta tus. Inclusion of these novel taxa is not only justified but also necessary for an accurate representation of ichthyofau Ea Figure 9.3. (A) Five major hydrographie ecoregions recognized in this study, large number of undescribed species results in part from in comprising the pastprn highlands and lowlands, the western basins, the rivers and tensive collecting efforts during the past decade, often fo lakes of northwestern Madagascar. and the southern headwaters. The figures in boxes indicate the total number of native freshwater species (- spp.) recorded cusing on remote a reas of the island-such as the :Vtasoala from the particular ecoregion and the number of those species endemie (= eer) Peninsula, headwater regions in the norrhwest, eastern and to that particular eco region. Shading indicates areas in need of additional ichthyo western basins of the southern highlands nea r Andringitra, faunal survey. (8) Cross-sectional relief map of Madagascar, illustrating the wide western plain and narrow. steep eastern escarpment. and northeastern drainages-thar were previously unsur veyed. The great majority of undescribed species are mem bers of the Bedotiidae and Cichlidae, reflecting in part a greater taxonomie discrimination, as these are the only two western drainages encompassed by this region, e.g., of the groups of Malagasy freshwater fishes that have been subject Sofia, Mahajamba, Kamoro, Betsiboka, Rantabe, and Ma to recent revisional study (e.g., Stiassny 1990; Reinthal and rimbona Rivers), the headwaters of the Tsaratanana Massif Sriassny 1997; Sparks and Reinthal 1999, 2001; Sparks in the north, and the forested regions of the southeastern 2001 b, 2002; Stiassny et aL 2001 ). highlands (especially south of the Mananara drainage ba Here we considera taxon as a "freshwater" species if ir sin) (fig. 9.3A). is generally collected in, is commonly found weil inland in, With few exceptions, species listed in table 9.1 that were oris restricted to completely freshwarer habitats. Following not collected persona li y or by collaborators (i.e., those listed this definition we also include species whose life histories in recent global compendiums such as Daget et aL 1984, are poorly known but rhat appear to spend a significant 1986; Eschmeyer 1998) have been verified by examination portion of their li fe in fresh waters, as opposed to entering of existing museum collections. Our main concern was to fresh water for the sole purpose of reproduction. Our in compile an accurare, up-to-date list of the native fishes in terpretation errs on the conservarive side and may underes habiting the inland waters of Madagascar. Our aim was to timate the crue diversity of native Malagasy fr eshwater fish be as conserva rive as possible but to re present full y the true species. For example, we have not included severa! species ichthyofaunal diversity on the island. Several species have of carangids (jacks), lutjanids (snappers), gerreids (mojar not been collected in recent years, and for these we relied ras), sparids (porgies), and haemulids (grunts), in addition on museum records and specimens to verify their occur- to a .number of othee species belonging to marine familics J. S. Sparks and M. l. J. Stiassny 857 thar are frequently collecred weil inland and in freshwater rivers have depauperate fish assemblages, frequently com habitats. Ir should be noted rhat among ichthyologists rhere posed of only a few goby or eleotrid species (gobioids) or are differences in the definition of a "freshwater .. species, both. Eels (Anguilla spp.) are also present in these regions and lists vary somewhat in terms of the inclusion and ex where there are no significant barriers to upstream dis clusion of these taxa. persal (i.e., waterfalls). According to Kiener (1963), only ln table 9.1 we list 143 native freshwarer species, be gobioids, eels, and the cichlids Paratilapia pol/eni and longing to 21 families and 54 genera; 93 of rhese species Ptychochrom"oides betsileanus have distributions extend (>65%) are endemie to Madagascar, whereas 99 species ing above 1000 rn, although in recent ichthyofaunal surveys (>69%) are endemie to the Malagasy region (including neither of these genera has been found above 1000 m. Madagascar, the Comoro Islands, the Mascarene Islands of ln contrast, wesrern Madagascar is much drier (average La Réunion, Mauritius, and Rodrigues, and the Seychelles). annual rainfall is only about 25% th at of the eastern slopes) Malagasy freshwarer fish endemism is 60-90% greater and characterized by longer, generally slow-flowing rivees than thar reporred in recent studies (table 9.1, fig. 9.1). For subject to much seasonal fluctuation in water leve\ and flow example, Kiener and Richard-Vindard (1972) recorded 32 rate (figs. 9.2B and 9.3B) and shallow, extremely turbid, endemie species, Stiassny and Raminosoa (1994) 42 spe· oligorrophic floodplain lakes (fig. 9.2C). Many of the cies, and de Rham (1996) 49 species. Most recently Ben smaller river basins are dry from April to November {AI stead er al. (2000) lise a tora! of 64 endemie species, of which degheri 1972). The rivers, and to a lesser extent also the 58 have been verified following our definition of freshwater lakes, of western coastal Madagascar are characterized by taxa. This remarkable increase in the number of native numerous intrusive marine species, many of which are fre freshwater fishes underscores the importance of continued quently collected far inland (Kiener 1965}. This is largely efforts to collect in remere regions of the island. At higher due to an expansive continental shelf extending along most taxonomie ranks endemism is muted, with only two en of the west coast and the presence of numerous coral reefs demie families (9.5%) and 13 endemie genera (24.5%) in the region with large fish populations (fig. 9.3B; Brenon recorded from the island (cable 9.1). 1972). Western rivers have significanr ridai influence in their lower reaches (Kiener and Richard-Vindard 1972), fa cilitating colonization and recolonization by marine forms Hydrology and Fish Communities after periods of drought have extirpated freshwater species inhabiting these regions. Aldegheri ( 1972, p. 261) di vides Madagascar into five ma A significant result of the present study is the recognition jor hydrographie regions: the slopes of Montagne d'Ambre of a second major region of ichchyofaunal diversity in Mad in· the far north, drainages of the Tsaratanana Massif in agascar: the rivers and floodplain lakes of the northwest, the north, eastern drainages, western and norchwcstern ba and the subdivision of the eastern region, based on an ele sins, and southern basins. Although endemie fish species vational disjonction in species distribution, into the eastern are found in each of thcse regions, we restricc our discus· highlands and lowlands (see also Sparks and Stiassny in sion to the regions with highcr ichthyofaunal diversity, in press) (rable 9.1 and fig. 9.3A). A total of 71 native fresh cluding the eastern highlands and lowlands, the western ba water species are recorded from northwesrern rivers and sins, and the rivees and lakes of northwestern Madagascar lakes, 69 species from the eastern lowlands, and 51 species (fig. 9.3A). These regions were not selected arbitrarily but from the eastern highlands (rable 9.1, fig. 9.3A). Fifty-seven conform to broad patterns of endemism. native species have distributions restricted to eastern Tradicionally, two major ichthyofaunal regions have drainages, occurring in either the eastern highlands or low beèn recognized: the east-coast drainages, with the high lands or both, whereas 48 native species are entirely re est diversicy of freshwater fishes on the island (Kiener and stricted to western drainages. In their entirety, the eastern Richard-Vindard 1972), a nd the much drier and suppos drainages therefore represent the most species-rich hydro edly species·poor western basins. East-coast drainages emp logie region of the island. However, if the upper and lower tying into the Indian Ocean are characteristically steep with eastern basins are considered separately, as seems appro many rapids and cascades (fig. 9.2A). The rivers are shore priate given substantial differences in the fish assemblages and generally clcar and termina te on a ~arrow coastal plain present in each, the northwestern basins are the most spe· over a narrow continental shelf. The sccep eastern slopes ciose and a Iso harbor rhe most species endemie to a partic constitute approximately 25% of the total area of Mada ular ecoregion (table 9.1, fig. 9.3A). Further, species diver gascar (Aidegheri 1972; fig. 9 .3B) and are subject to high sity in the northwest is likely underestimated, as a majority average annual rainfall. The headwaters of many eastern of the basins draining the Tsararanana Massif, as weil as a 858 Fishes Introduction number of other basins in nonhwestern Madagascar, re dissolved carbonates. Again, dissolved oxygen content was main unsun•eyed (see fig. 9.3A). found to be similar regardless of hydrologie region. Eastern and many northwestern basins, especially those draining the Tsaratanana Massif, receive more rainfall and are more diverse geographically than the drier western and Overview of the Freshwater Fish Fau na sourhern basins. Rivers in eastern and northwestern Mada gascar are also Jess subject to large seasonal fluctuation in Madagascar's ichthyofauna is numerically dominated by flow rate (Aidegheri 1972; Donque 1972). Most western members of the Cichlidae, Bedotiidae, Gobiidae, Eleotri basins experience periods of very reduced flow or complete dae, Anchariidae, Mugilidae, Anguillidae, and Aplochei desiccation during the dry season extending from April un lidae {table 9.1). Small endemie radiations of bedotiids til November (Donque 1972), which could easily wipe out (endemie family; two genera), cichlids (five genera, ali en any existing populations of freshwater fishes inhabiting demie), aplocheilids (one genus, endemie to Madagascar these areas. This pattern of seasonal desiccation likely ac and granitic Seychelles), and anchariids (endemie family; counts for the very depauperate assemblages of freshwater one genus) characterize the insular rivers, streams, and fishes inhabiting western basins, which in general are dom lakes. However, the majority of families with members pres inated by marine forms. ent on Madagascar are primarily marine and are frequent! y ln addition to these three primary regions of ichthyofau colonizers of oceanic islands. These include nwmbers of nal diversity, a number of localized areas with unique and the Gobiidae, Eleotridae, Mugilidae, Ariidae, Syngnathi interesting fish assemblages are found throughout Mada dae, Anguillidae, Ambassidae, and Kuhliidae. lnterestingly, gascar. These indude the tshrgy formations of the nort hern other than native eels of the genus Anguilla, the island Jacks and western regions of the island and the numerous lime large predatory species, but as discussed later in this ch J. S. Sparks and M. L. J. Stiassny 861 Asian sicydiine (rock-climbing) gobies of the genus Sicy deposits on Madagascar (Gottfried and Krause 1998). This opterus is hypothesized (Sparks and Nelson in prep.). Such recent discovery supports our contention thar the current · .historical biogeographie patterns elucidated by phylogeny absence of fossil evidence corroborating the early presence provide insight into evolutionary processes (i.e., were spe of Madagascar's extant freshwater fishes does not rule out ciation/diversification events coïncident with the appear the possibility thar their fossils will someday be discovered ance of a barrier [vicariance], or does the barrier predate there. speciation (dispersal]?), which canin turn be used to ana Jyze and explain present distributions (Lundberg 1993). Formulation and testing of historical hypotheses regard Conservation: Current and Future Threats ing the origins and diversification of Madagascar's fresh water fishes require knowledge not only of their phyloge Bensread er al. (2000) consider three main factors to ac nies but also of their spatial and temporal distributions. count for the current dire state of the Malagasy ichchy Congruent biogeographie patterns exhibited by a number ofauna: the degradation of aquatic habitats thar follows de of distantly related clades present a compelling argument forestation (fig. 9.20), overfishing, and competition from for vicariance (Rosen 1978). The sister-group relationships and predation by exotic species. To chis list we would add discussed earlier are consistent with current prevailing hy a "knowledge impediment," by which we mean a lack not potheses regarding the sequence of Gondwanan fragmenta only of comprehensive knowledge of the taxonomie com tion, given thar the connection of Madagascar, the granitic position and status of the island's ichthyofauna but also of Seychelles, and India was more recent than thar of Mada the most basic biology of the majority of species. gascar to other Gondwanan landmasses and given the po Des pire this knowledge impediment, what is ali too clear tential connecrion of South America, Madagascar/India, is thar sedimentation and increased rurbidity of river and and Australia via Antarctica, exclusive of Africa, thar may lake basins have major effects on native fish populations, have persisted weil into the Lare Cretaceous (Hay et al. whereas exotics seemingly thrive in and dominate these 1999). Despite the problems with this interpretation, it highly degraded habitats. Severa! species of tilapiine cich seems to us improbable thar these congruent distributional lids, introduced for aquaculture purposes decades ago (seè patterns could have resulted from numerous independent Reinthal and Stiassny 1991, table 4, for a complete list of intercontinental marine dispersals. ln light of these repeat introductions), compete for resources with native species, ing patterns, there is no need to contrive dispersalist sce and large exotic predators such as the Asian snakehead narios as alternative explanations, given thar vicariance is (Channa cf. striata) and black bass (Micropterus salmoides) the most parsimonious explanation of the observed distri prey heavily on native fishes. In particular, the introduction butions (Grande and Bernis 1999). Moreover, it is inadvis of the Asian snake head, a voracious predaror thar is rapidly able a priori to dismiss vicariance in intercontinental faunal spreading throughour the island, appeaxs to be having a comparisons, even in the absence of fossil data, unless ir can major impact on native fish populations (Benstead et al. be shawn for the organisms in question thar their closest 2000; ]. Sparks and M. Stiassny pers. observs.). Unfortu relatives are marine taxa (Lundberg 1993; Stiassny and narely, human-mediated disturbances will play an increas Raminosoa 1994). Based on our current systematic under· ingly significant role in the attrition rate of native species, as standing, we do not find this to be the case for the Bedoti Madagascar has one of the highesr population growth rates idae, Cichlidae, Aplocheilidae, or the ehiravin clupeid gen in the world ar 3.2% (Population Reference Bureau 1997- era discussed earlier. 2001; Kremen et al. 1999). Green and Sussman (1990), us Finally, we note thar paleontological studies in Mada ing Landsat images, esrimate thar annual forest loss in gascar concerning fish are few, and the fossil record for Madagascar is 1100 km2, whereas orher estimates range as many of the families in question is surprisingly poor, not high as 3000 km2 per year (Richard and O'Connor 1997). only in Madagascar but also worldwide (Patterson Problems associated with annual forest-cover Joss are dis 1993a,b; Murray 2000). As Grande and Cavender (1991) cussed elsewhere in this volume (see Dufils), and the out stress, there is a global paucity of Early Cretaceous through look is bleak. Overfishing, primarily with the use of gill Mid-Paleocene freshwater teleosr fossils, which is probably nets, is a major concern in sorne of the large floodplain attributable to a scarcity of fossil-bearing freshwater rocks lakes in the northwestern (including Lac Kinkony and Lac of Cretaceous age (Lundberg 1998). Given the nature of Andrapongy, as weil as the lakes in the region of Saro freshwater systems, the likelihood of preservation of an drano) and eastern regions of the island (coasrallakes of the cient freshwater faunas is significantly less than under ma northern Pangalanes Canal). rine conditions. Only recently have fossil gars, large and Ali of Madagascar's large lakes are curremly infested rather conspicuous animais, been discovered in Cretaceous wirh the Asian snakehead, which has already resulted in 862 Fishes Introduction dedining fish catches and will likely lead to the collapse region]), imraisland biogeographie patterns of fish distribu of native fisheries in the near future. Species that have only tions ha\·e rer to be fully investigared. recently been discovered, including Paretroplus menarambo As is the case in so many of the world's top conservation . (Allgayer 1996) from Lac Sarodrano in the northwest, are "hotspots," freshwater systems are frequently overlooked, now verging on extinction (or are extinct, as no additiona! and this has had tragic consequences not only for aquatic specimen of this recently described taxon has been collecred communities but also for the terrestrial systems thar depend si nee 1997), apparent!y as a direct result of heavy predation on them. ln Madagascar, river systems are commonly ex by the snakehead. A number of species appear already ro duded from protection, even if surrounded by prorected have succumbed to these pressures and are presumed ex· land, as these riparian areas are the most desirable for rinct (Harrison and Stiassny 1999). To these should be slash-and-burn agriculture and paddy rice production. This added an undescribed species of Ptycllochromoides from is not to say tbat conservation efforts are always futile. An Lac ltasy in the central highlands, an undescribed Ptycbo· ichth)·ofaunal survey of the Masoala Peninsula conducted chromis species from the Onilahy River basin in the south in recent years was instrumental in ensuring the inclusion of west, and Pantanodon madagascariensis from eastern river basins inro the design of the PN de Masoala (Kremen coastal swamps (]. Sparks and M. Stiassny unpubl. data).lt et al. 1999). Although in most cases protection of Mada has been suggested thar species inhabiting islands may be gascar's aquatic systems has not been a top priority, we more susceptible to extinction because of a high degree hope thar by presenting the freshwater fish fauna in a new of specialization and low b·els of competition wirh orher light, by srressing its importance for evolurionary studies, species (MacArthur and Wilson 1967; D'Antonio and Dud its high degree of vulnerability, and the current dire state of ley 1995), and this appears to hold true for the Malagasy the fauna as a whole, the conservation community will be ichrhyofauna. gin the process of fully inregrating aquarie habitats inro fu The vulnerability of the island's freshwarer ichrhyofauna ture conservation action. as a whole is exacerbated by extreme stenotopy of numer ous native species. Many endemie cichlids and bedotiids ex hibit restricted geographie distributions and are known Conclusions only from their type localities or at most a very localized a rea, frequently a single body of water or an isolated drain Alrhough our original intention was to present an in-depth age basin. Regional endemism is high (table 9.1, fig. 9.3A), discussion of conservation recommendations directed spe especially in the northwestern and eastern regions of the is cifically at preserving aquatic communities in Madagascar, land. Sparks and Rein thal ( 1999) present a currem distri we now believe rhat most of what we could suggest would bution map for members of Paretroplus, illustrating their faU far short of succeeding and wou Id most Jikely be futile. extremely localized distriburions in the northwest, and Sti We have both conducted research in a number of tropical assny and Rodriguez {200 1) depict similarly restricted dis regions, but neither of us has witnessed anyrhing surpass tributions for Rheocles species in the eastern drainages. In ing the degree and extent of environmental degradation in addition to Parctroplus and Rheocles, other highly steno Madagascar. The freshwater fish fauna of Madagascar is al tapie species include Oxylapia po/li, Ptychochromoides ready so heavily affected that it is likely too late to save ali katria, Pantmwdo11nov. sp. "manombo," Teramulus water but small remnants. Madagascar willlikely be one of many loti, Glossigobius ankararrensis, and the species of T;•phleo• large islands to have its native floras and faunas heavily af tris restricted to limestone caves in southwestern Madagas fected by human influence. car, to name but a few. As Raxworrhy and Nussbaum Our position may be interpreted as overly pessimistic, (1997) point out, interest in the biogeography of Madagas but that is partly our intention. We do not believe it helpful car's flora and fau na has been high at a global scale, but rel to propose a series of emergency measures to "save" what atively little attention has been directed at within-island remains, when in fact we believe that most of these mea biogeographie patterns for vertebrates. Although severa! re sures would prove tao little and much too lare. At least for gions with highly endemie fish communities can be iden the rime being, in certain isolated parts of the island, in tified (e.g., northwestern lakes and basins, the basins of the cluding the Masoala Peninsula and remote regions in the Mangoro, Ankofia, and Mangarahara, and Lac Kinkony), east and northwest, forested basins remain, and every effort including disjunct geographie regions wirh interesting sim must be made to save them. The large offshore island of ilarities in ichthyofaunal composition suggestive of recent Nosy Be is currently free of exotic predators (P. V_ Loiselle hydrologie connection {e.g., southwestern Madagascar unpubl. data), retains a native ichthyofauna, and must !Isalo region}, southeastern highlands [Vevembe-Vondrozo be considered a top conservation priority. Unfortunately, J. S. Sparks and M. L. J. Stiassny 863 snakehead fry have been discovered on Madagascar's other rection of vulnerable island freshwarer ecosystems else large offshore island, Ile Sainte Marie (]. P. Benstead un where in the world. pub!. data), and likely foreshadow the demise of this is \and's native fish fauna. The situation throughout much of western, northwest ern, central, and eastern Madagascar is far direr. A number Acknowledgments of small forested regions have been afforded protection, but these reserves and parks do little in the sense of offering pro We are extremely grateful to numerous colleagues rhrough tection to entire river basins, given thar aquaric systems are out the world for their help with this project. Ali have been so vulnerable to upstream influences. Many of Madagas generous with their time and insights into Malagasy fishes car's reserves are sim ply too small to maintain via ble popu and often also in providing us with data and specimens for lations of native fish species, especially species thar must this study. ln parricular, we thank Paul Loiselle, who has migrate either short or long distances during reproduction been a resource of inestimable value throughom the study. or thar require large and diverse habitats. His input on an earlier dra ft of this chapter is much appre Extremely localized distributions and concentrated re ciated and much improved the final product. Thanks a iso to gional diversity point to a particular vulnerability of the Chris Raxworrhy for commenting on an earlier dra ft of this Malagasy ichthyofauna as a whole. Species are generally manuscript. Our thanks also to Robin Abel! and Michele represented in smaller areas of their overa\1 range and may Thieme, whose efforts associated wirh the WWF freshwater not be affected by initial restricted habitat destruction (or assessment of Africa have been a source of inspiration. It in the case of Madagascar's freshwater fishes, distributions was at their urging thar we firsr began the process of assim are generally very localized, and populations may escape ilating data on Malagasy fishes, and we are appreciative of initial habitat destruction). Although habitat loss may ini their ongoing moral support. Thanks to Karen Riseng, tially cause relative! y few extinctions, eventually many will Franco Andreone,Jean Claude Nourissat, Patrick de Rham, result as the last p;ucels are destroyed (Pimm and Raven Alex Saunders, Paul Loiselle, and John Barnes for providing 2000). Nowhere is this more truc than in Madagascar, us wirh data and specimens from recent field work and to which is poised for a "breaking wave" of species extinction Patrice Pruvost and Guy Duhamel (Paris), Darrel Siebert in the coming decade. To date, endemie and native fish spe and Oliver Crimmen (London), Martien van Oijen (Lei cies have becn completely replaced by exotics across most den), Barb Brown (New York), Susan Jewert (Washington, of the central highlands and throughout much of the west D.C.), and Claude Weber (Geneva) for sending materials on (Reinthal and Stiassny 1991; J. Sparks and M. Stiassny un loan. Doug Nelson (Ann Arbor) was extremely helpful with pub!. data) . Somc 23 cxotic specics have been deliberarely the curation of numerous materials. introduced into the island's freshwatcr systems dating from For assistance in Madagascar we are exrremely grateful the mid-1800s, not to mention a number of accidentai es ro Noro Raminosoa, Peter Reinthal, and Patricia Wright. capees from aquaculture in recent deçades {Reinthal and Collecring efforts were facilitated by Benjamin Andriama Stiassny 1991; Bensread et al. 2000). Unless drastic mea haja and Ml CET (Institute for the Conservation of Tropical sures are undertaken to protect this fragile fauna, as has Environments, Madagascar) staff, and we are grateful for been the case for many of Madagascar's terrestrial organ their support. Collection permits were obtained from the isms, much of the island's native freshwater fishes will be Direction des Eaux et Forêts and the Association Nationale )ost forever. Given the islandwide spread of exotics, such pour la Gestion des Aires Protégées (ANGAP). Melanie L. measures will have to include captive breeding programs J. Stiassny acknowledges the ongoing support of an Axel {see Loise!le, "Captive Breeding for the Freshwater Fishes cod Curatorship. John S. Sparks's work was funded by of Madagascar," this volume), the poisoning of lakes and grants from the National Science Foundation (DEB- rivers to eliminate these introduced species, and restocking 9300996), the United States Agency for International De with native species, not to mention large·scale restoration velopment (University Development Linkage Program, US of these degraded habitats. However, as Benstead et al. AID Cooperative Agreement, PCE-5063-A-00-3035-00) (2000) point out, no restoration projects are currently in given to Peter Reimhal, and the Carl L. and Laura C. progress or planned. Although it may already be too lare to Hubbs Research Fellowship; support from the Rackham save ali but remnants of Madagascar's unique freshwarer School of Graduate Studies of the University of Michigan; ichthyofauna, it is our hope thar this tragic story will serve and a collection study grant awarded through the American as a warning and underscore the importance of carly pro- Museum of Natural History. Aam. and lvantsoff, W. 1997. Descriptive aoatomy of ûtimsichthys gascar. Mémoires cie rJnstitut Scientifique cie Maœgascar. A rhombosomoides and triatil@rina wr:ffll!fi (Teleostei: Atheroni· 1:169-76. formes). and a phylogenetic analysis of Melanotaeniidae. Bleeker, P. 1868. Description de trois esp«es inédites de Chromi lchthyologic.31 Exploration of Freshwaters 8 : 107-50. doides cie Madagascar. Vers/agen en Medeedelingen der Alayo. P. O. 1973. Lista depeces fluviatiles de Cuba. Torreia. Havana Koninklijke, Akaclemie van Wetenschappen. Afdeeling Natu 29: 1-SS. rukunde. Amsterdam 2(11 ): 307-14. Aldegheri. M 1972. Rive~ and streams on Madagascar. ln Bioge· Bleeker. P.• and Ponen. F. 1875. Poissons de Madagdscar er cie l'lie de ography and eco/ogy in Madagascar. eds. R. Battistini and la Reunion. Leiden: E. J. Brill . G. Richard·Vindard, pp. 261-310. The Hague: W. Junk. Boen. P. 1. Davies, K. J., and Petts. G. E. (eds.). 2000. Global perspec Allen. G. R. 1989. Freshwater fishes of Australia. Neptune City.~ til'l:'s on riv --. 1998. Phylogenetic relationships of Neotropical Siluriformes: tion and taxonomie utility. Bulletin of the British Museum (Nat Historical overview and synthesis of hypotheses. ln Phylogeny ura/ History): Zoo/ogy 57: 111-32. and classifiCation of Neotropical fishes, eds. L. R. Malabarba, Harrison. 1. J.. and Stiassny, M.L.J. 1999. The quiet crisis: A preliminary R. E. Reis, R. P. Vari, Z.M.S. lucena. and C.A.S. lucena, pp. 49- listing of freshwater fishes of the world that are either extinct 68. Porto Alegre, Brazil: Edita ra Universitaria da Pontificia Uni or "missing in action." ln Extinctions in near time: Causes. con versidade Cat61ica do Rio Grande do Sul. texts, and consequences, ed. R.D.E. MacPhee, pp. 271-331. de Rham, P. H. 1996. Poissons des eaux intérieures de Madagascar. ln New York and london: Kluwer Academie/Plenum. Biogéographie de Madagascar, ed. W. R. lourenço, pp. 423- Hay, W. W., DeConto, R. M .. Wold, C. N., Wilson, K. M .. Voight, S.. 40. Paris: ORSTOM. Schulz. M., Wold, A. R.• Dullo, W-C., Ronov. A. B. • Balukhov Donque, G. 1972. The dimatology of Madagascar. ln Biogeography sky, A. N., and Sëding, E. 1999. Alternative global Cretaceous and eco/ogy in Madagascar. eds. R. Battistini and G. Richard paleogeography. ln Evolution of the Cretaceous oŒan-climate Vindard, pp. 87-144. The Hague: W. Junk. system, eds. E. Barrera and C. C. Johnson, pp. 1-47. Special Oyer, B. S., and Chernoff, B. 1996. Phylogenetic relationships among paper 332. Boulder: Geological Society of America. atheriniform fishes (Teleostei: Atherinomorpha). Zoological Inger, R.F., and Kong, C. P. 1962. Freshwater fishes of North Borneo. Journal of the Linnean Society 117: 1-69. Chicago: Chicago Natural History Museum. Eschmeyer, W. N. 1998. Catalog offishes. San Francisco: California Jenkins, M. O. 1987. Madagascar: An environmental profile. Gland: Academy of Sciences. IUCN. Fitzsimons. J. M., and Nishimoto, R. T. 1990. Territories and site tenac Kiener, A. 1963. Poissons, pêche et pisciculture a Madagascar. Centre ity in males of the Hawaiian stream goby Lentipes concolor Technique Forestier Tropica/24: 1- 244. (Pisces: Gobiidae). lchthyological Exploration of Freshwaters --. Contribution a l'étude écologique et biologique des eaux 1:185-89. sa'umAtresmalgaches. VieetMi/lieu. C 16(2):10 13-1149. Glaw. F., and Vences, M. 1994. A fieldguide to the amphibians and Kiener, A., and Maugé, M. 1966. Contribution a l'étude systématique reptiles of Madagascar. 2nd edition. Cologne: Vences and et écologique des poissons Cichlidae endémiques de Madagas GlawVerlag. car. Mémoires Muséum National d'Histoire Naturelle, Paris Goodman, S. M. (ed.). 2000. A floral and faunal inventory of the Parc 40:51-99. National de Marojejy. Madagascar: With reference to eleva Kiener, A., and Richard-Vindard, G. 1972. Fishes of the continental tional variation. Fie/diana: Zoo/ogy. new series 97: 1-286. waters of Madagascar. ln Biogeography and eco/ogy in Mada Gottfried, M. O., and Krause, D. W. 1994. tate Cretaceous fishes from gascar. eds. R. Battistini and G. Richard-Vindard, pp. 477-99. . Madagascar: A first look. Journa l of Vertebra te Paleontology The Hague: W. Junk. 14 (Suppi.):26A. Kottelat, M. 1998. Fishes of the Nam Theun and Xe 8anfai basins. --. 1998. First record of gars (tepisosteidae, Actinopterygii) on Laos. with diagnoses of twenty-two new species (Teleostei: Madagascar: late Cretaceous remains from the Mahajunga Cyprinidae. Balitoridae. Cobitidae. Coiidae and Odontobuti basin. Journal of Vertebrate Paleontology 18:275-79. dae). lchthyological Exploration of Freshwaters 9(1 ): 1-128. Gottfried. M. 0., Randriamiarimanana, l. L., Rabarison, J. A., and Krause, O. W.• Prasad, G.V.R., von Koenigswald, w., Sahni, A., and Krause, D. W. 1998. tate Cretaceous fish from Madagascar: Grine, F. E. 1997a. Cosmopolitanism among Gondwanan tate Implications for Gondwanan biogeography. Journal of Afri Cretaceous mammals. Nature 390 : 504-7. can Earth Sciences, Special Abstracts issue. Gondwana 10: Krause, D. W., Hartman, J.H., and Wells, N. A. 1997b. late Creta event stratigraphy of Gondwana, 27, number lA, published ceous vertebrales from Madagascar: Implications for biotic abstract. change in deep ti me. ln Natural change and human impact Grande. l. 1985. Recent and fossil clupeomorph fishes with materials in Madagascar, eds. S. M. Goodman and B. D. Patterson, for revision of the subgroups of clupeoids. Bulletin of the pp. 3- 43. Washington, D.C.: Smithsonian Institution Press. American Museum of Na tura/ History 181:235-372. Kremen, C., Razafimahatratra, V., Guillery, R. P.• Rakotomalala, J.. Grande, l., and Bernis, W. E. 1999. Historical biogeography and his Weiss, A., and Ratsisompatrarivo, J.-S. 1999. Designing the torical paleoecology of Amiidae and ether halecomorph fishes. Masoala National Park in Madagascar based on biological and ln Mesozoic fishes 2-systematics and fossil record. eds. G. Ar socioeconomic data. Conservation Bio/ogy 13: 105S-68. ratia and H.-P. Shultze, pp. 413-24. Munich: Verlag Dr. Fried lundberg, J. G. 1993. African-South American freshwater fish clades rich Pleil. and continental drift: Problems with a paradigm. ln Biological Grande, L.. and Cavender, T. M. 1991. Description and phylogenetic relationships between Africa and South America, ed. P. Gold reassessment of the monotypic Ostariostomidae (Teleostei). blatt, pp. 156-99. New Haven: Yale University Press. Journal of Vertebrate Paleontology 11 :405-16. --. 1998. The temporal context for the diversification of Nec Grandidier, G., and Petit, G. 1932. les poissons d'eau douce. ln Zo tropical fi shes. ln Phylogeny and classification of Neotropical ologie de Madagascar. pp. 184-88. Paris: Société d'Editions fishes, eds. l. R. Malabarba. R. E. Reis. R. P. Vari, Z.M.S. Lu Géographiques. Maritimes et Coloniales. cena, and C.A.S. Lucena, pp. 49-68. Porto Alegre, Brazil: Green, G. M .• and Sussman, R. W. 1990. Deforestation history of the EDIPUCRS. eastern rain forest of Madagascar from satellite images. Sci Lundberg, J. G., Kottelat, M., Smith, G. R., Stiassny, M.L.J., and Gill, ence 248:212-1 S. A. C. 2000. So many fishes, so little time: An overview of re· Harrison, 1. J., and Howes, G. J. 1991. The pharygnobranchial organ of cent ichthyological discovery in continental waters. Annals Mis mugilid fishes: lts structure, variability, ontogeny, possible func- souri Botanical Garden 87:26-62. References 881 MacArthur, R. H., and Wilson, E. O. 1967. The theory ofisland bio Rand McNally. 1987. Universal world atlas. Chicago: Rand McNally. geography. No. 1 of Monographs in population bio/ogy. Ra xworthy, C. J. . and Nussbaum, R. A. 1997. Biogeographie patterns Princeton: Princeton University Press. of reptiles in eastern Madagascar. ln Natural change and hu Maisey, J. G. 1993. Tectonics, the Santana Lagerstatten, and the impli man impact in Madagascar, eds. S. M. Goodman and B. O. cations for la te Gondwanan biogeography. ln Biological rela Patterson, pp. 124-41. Washington, O.C.: Smithsonian lnstitu· tionships between Africa and South America, ed. P. Goldblatt, tion Press. pp. 435 - 54. New Haven: Yale University Press. Rein thal, P. N., and Stiassny, M.L.J. 1991. The freshwater fishes of McOowall, R. M. 1990. When galaxiid and salmonid fishes meet-a Madagascar: A study of an endangered fauna with recommen family reunion in New Zealand. Journal of Fish Bio/ogy dations for a conservation strategy. Conservation Bio/ogy 37(Suppl. A):35-43. 5:231-43. --. 1996. Introduction. ln Freshwater fishes of southeastern Aus --. 1997. Revision of the Madagascan genus Ptychochromoides tralia, ed. R. M. McOowall, pp. 9- 14. Sydney: A. H. and A. W. (Teleostei: Cichlidae), with a description of a new species. Reed. khthyological Exploration of Freshwaters 7: 353-68. Mo, T. 1991 . Anatomy, relationships and systematics of the Bagridae Richard, A. F., and O'Connor, S. 1997. The past, present, and possible (Teleostei, Siluroidei}-with a hypothesis of siluroid phylogeny. future of Madagascar's environment. ln Natural change and Thesis Zoologicae 17:1-216. human impact in Madagascar. eds. S. M. Goodman and 8. O. Moyle, P. B., and Cech Jr., J. J. 1996. Fishes: An introduction ro ichthy· Patterson, pp. 406-18. Washington, O.C.: Smithsonian Institu ology. 3rd edition. Upper Saddle River, New Jersey: Prentice tion Press. Hall. Riseng, K. J. 1997. The distribution of fishes and the conservation of Munro, I.S.R. 1967. The fishes of New Guinea. Sydney: Victor C. N. aquatiç resources in Madagascar. Master's thesis, University of Blight. Michigan, Ann Arbor. Murray, A. 2000. Eocene cichlid fishes from Tanzania, East Africa. Rosen, 0. E. 1965. Oryzias madagascariensis Arnoult redescribed and Journal of Vertebrate Paleontology 20:651-64. assigned to the East African fish genus Pantanodon (Atherin Myers, G. S. 1938. Fresh-water fishes and West lndian zoogeography. formes. Cyprinodontoidei). American Museum Novitates Annual Report of the Smithsonian Institution 1937:339-64. 2240:1-10. Nelson, J. S. 1994. Fishes of the world. 3rd edition. New York: John --. 1978. Vicariant patterns and historical explanations in bio Wiley and Sons. geography. Systematic Zoo/ogy 27 : 159-88. Ng, H. H., and Sparks, J. S. Submitted. The ariid catfishes (Teleostei: Rosen, D. E., and Parenti, l. R. 1981. Relationships of Oryzias. and the Siluriformes: Ariidae) of Madagascar, with the description of groups of atherinomorph fishes. American Museum Novitates two new species. Occasional Papers of the Museum of Zool 2719:1-25. ogy. University of Michigan. Sampson, S. D., Witmer, L. M., Forster, C., Krause, D. W., O'Connor. Parenti, L. R. 1981 . A phytogenetic and biogeographie analysis of P. M., Dodson, P., and Ravoavy, F. 1998. Predatory dinosaur re cyprinodontiform fishes (Teleostei: Atherinomorpha). Bulletin mains from Madagascar: Implications for the Cretaceous bio of theAmerican Museum of Natural History 168:335-557. geography of Gondwana. Science 280: 1048-51 . --. 1984. On the relationships of phallostethid fishes (Atheri Sauvage, H. 1891. Histoire naturelle des poissons. Vol. 16 of Collec nomorpha), with notes on the anatomy of Phallostethus tion Histoire Physique. Naturelle, Politique de Madagascar. dunckeri Regan, 1913. American Museum Novitates 2779 : Paris: Imprimerie Nationale. 1-12. Seegers, L. 1996. The fishes of the Lake Rukwa drainage. Annales de Patterson, C. 1993a. An overview of the early fossil record of acan la Société Zoologique de Belgique 278 :1-407. thomorphs. Bulletin of Marine Science 52 :29-59. Skelton, P. H. 1990. The conservation and status of threatened fishes --. 1993b. Osteichthyes, Teleostei. ln The fossil record 2, ed. in southern Africa. Journal of Fish Bio/ogy 37(Supp\. A):87-95. M. Benton, pp. 621-56. London: Chapman and Hall. Smith, J.L.B. 1965. Fishes of the family Atherinidae of the Red Sea and Pellegrin, J. 1933. Les poissons des eaux douces de Madagascar et des the Western lndian Ocean with a new freshwater ge nus and iles voisines. Mémoires de l'Académie Malgache 14:1- 224. species from Madagascar. lchthyological Bulletin Rhodes Uni Pethiyagoda, R. 1991. Freshwater fishes of Sri Lanka. Colombo: Wild versity31 :601-32. life Heritage Trust. Sparks, J. S. 2001 a. Bedotia masoala: A new species of atherinoid Pimm, S. L., and Raven, P. 2000. Extinction by numbers. Nature rainbowfish (Teleostei: Bedotiidae) from the Masoala Peninsula. 403 :843- 45. northeastern Madagascar. Copeia 2001(2):482-89. Plummer. Ph. S., and Belle, E. R. 1995. Mesozoic tectono-stratigraphic --. 200 1b. Phyfogeny and biogeography of the Malagasy and evolution of the Seychelles microcontinent. Sedimentary Geel south Asian cichlid fishes (Teleostei: Perciformes: Cichlidae). in ogy 96:73-91. cluding a survey of freshwater fishes of Madagascar. Ph.D. the Pellard, O. A. Ingram, B. A., Harris, J.H., and Reynolds, L. F. 1990. sis, University of Michigan, Ann Arbor. Threatened fishes in Australia-an overview. Journal of Fish Bi --. 2002. Ptychochromis inornatus, a new cichlid (Teleostei: o/ogy 37(Suppl. A):67-78. Cichlidae) from northwestern Madagascar, with a discussion Population Reference Bureau. 1997-2001. Data available online at: of intrageneric variation in Ptychochromis. Copeia 2002 : www.prb.org/pdf/Madagascar_Eng.pdf. 120-30. Rabinowitz. P. O., Coffin, M. F., and Falvey, O. 1983. The separation of - -. ln press. Paretroplus dambabe, a new cichlid fish (T~Ieostei : Madagascar and Africa. Science 220:67-69. Cichlidae) from northwestern Madagascar, with a discussion 882 Fishes on the status of P. petiti. Proceedings of the Biological Society brackish water fishes. Geographical overviews, Symposium of Washington. PARADI. eds. G. G. Teugels, J. -F. Geugan, and J..J. Albaret. Sparks, J. S., and Reinthal, P. N. 1999. Paretroplus maromandia, a new Annales Muséum Royal de l'Afrique Centrale, Sciences Zoolo· ckhlid fish from the northwest of Madagascar. Occasional Pa giques 275: 133-49. pers. Museum of Zoo/ogy. University of Michigan 727:1-18. Stiassny, M.l.J., and Rodriguez, O. M. 200t. Rheocles derhami, a new --. 2001 . A new species of Ptychochromoides from southeastern species of freshwater rainbowfish (Atherinomorpha: Bedoti Madagascar (Teleostei: Cichlidae), with comments on the idae) from the Ambomboa River in northeastern Madagascar. monophyly and relationships of the ptychochromine cichlids. lchthyo/ogical Exploration of Freshwaters 12 :97-104. lchthyological Exploration of Freshwaters 12 : 115-32. Stiassny, M.l.J., Chak.rabarty, P., and Loiselle, P. V. 2001. Relationships Sparks, J. S., and Stiassny, M.l.J. ln press. Madagascar's freshwater of the Madagascan cichlid genus Paretroplus. with description fishes, an imperiled treasure. ln Freshwater ecoregions of of a new species from the Betsiboka River drainage of north Africa. A conservation assessment, eds. M. Thieme, R. Abell, western Madagascar. khthyological Exploration of Freshwaters M.L.J. Stiassny, D. Olsen, E. Dinerstein, J. D'Arnica, and E. Un 12 :29-40. derwood. Washington, D.C.: World Wildlife Fund-U.S. Storey, B. C. 1995. The role of mantle plumes in continental breakup: Stiassny, M.l.J. 1990. Notes on the anatomy and relationships of the Case histories from Gondwanaland. Narure 377 :301 - 8. bedotiid fishes of Madagascar, with a taxonomie revision of Storey, M., Mahoney, J. J., Saunders, A. D .• Duncan, R. A., Kelly, S. P., the genus Rheocles (Atherinomorpha: Bedotiidae). American and Coffin, M.F. 1995. Timing of hot spot-related volcan Museum Novitates 2979:1-33. ism and the breakup of Madagascar and lndia. Science 267: --. 1991 . Phylogenetic intrarelationships of the family Cichlidae: 852-55. An overview. ln Cichlid fishes: Behaviour, eco/ogy, and evolu Talwar, P. K., and Jhingran, A. G. 1992. /nland fishes of lndia and ad tion, ed. M.H.A. Keenleyside, pp. 1-35. London: Chapman and jacent countries. Vols. 1 and 2. Rotterdam: A. A. Balkema. Hall. Taylor. W. R. 1986. Ariidae. ln Checklist of the freshwater fishes of --. 1992. Phylogenetic analysis and the role of systematics in the Africa, eds. J. Daget, J.-P. Gosse, and D.F.E. Thys van den Aude· biodiversity crisis. ln Systematics, eco/ogy and the biodiversity naerde, pp. 153-59. Vol. 2. Brussels, Tervuren, and Paris: lnsti· crisis, ed. N. Eldredge, pp. 109-20. New York: Columbia Uni tut Royal des Sciences Naturelles de Belgique, Musée Royal de versity Press. l'Afrique Centrale, and Office de la Recherche Scientifique et --. 1996. An overview of freshwater biodiversity: With sorne les· Technique Outre-Mer. sons from African fishes. Fisheries 21 :7-13. Teugels, G. G., Janssens. l.J.M .. Bogaert, J., and Dumalin, M. 1985. - - . 2002. Revision of Sauvage/la Bertin (Ciupeidae; Pellonulinae; Sur une collection de poissons de rivière des Comores. Cybium Ehiravini) with a description of a new species from the fresh 9:41-56. waters of Madagascar and diagnosis of the Ehiravini. Copeia Vari, R. P., and Malabarba, l. R. 1998. Neotropical ichthyology: An 2002 :67-76. overview. ln Phy/ogeny and classification of Neotropicaf fishes. Stiassny, M.l.J., and de Pinna, M.C.C. 1994. Basal taxa and the role of eds. l. R. Malabarba, R. E. Reis, R. P. Vari, Z.M.S. Lucena, and cladistk patterns in the evaluation of conservation priori1ies: A C.A.S. Lucena, pp. 1-11. Porto Alegre, Brazil: EDIPUCRS. view from freshwater. ln Systematics and conservation evalua Vergara, R. R. 1980. Principales caracteristicas de la ictiofauna dul tion, eds. P. l. Forey, C. J. Humphries, and R. 1. Vane-Wright, ceacuicola cubana. Ciencias Biologicas 5:95- 106. pp. 235-49. Systematic Association special vol. 50. Oxford: Whitehead, P.J. P. 1962. The Pantanodontinae, edentulous toothcarps Clarendon Press. from East Africa. Bulletin of the British Museum (Natural His Stiassny, M.l.J., and Gerstner, C. L 1992. The parental care behaviour tory), Zoo/ogy 9:105-37. of Paratilapia pol/eni Bleeker, 1868 (Perciformes, labroidei), a Williams, J. E. • and Miller, R. R. 1990. Conservation status of the phylogenetically primitive cichlid from Madagascar, with a dis North American fish fauna in fresh water. Journal of Fish Biol cussion of the evolution of maternai care in the family Cichli ogy 37(Suppl. A):79-S5. dae. Environmenta/BiologyofFishes 34:219-33. Wright, P. C. 1997. The future of biodiversity in Madagascar: A view Stiassny, M.l.J., and Mezey, J. 1993. Egg attachment systems in the from Ranomafana National Park. ln Natural change and human family Cichlidae (Perciformes: Labroidei), with sorne comment impact in Madagascar. eds. S. M. Goodman and B. D. Patter on their significance for phylogenetic studies. American Mu son, pp. 381-405. Washington, D.C.: Smithsonian Institution seum Novitates 3058: 1-11. Press. Stiassny, M.LJ., and Raminosoa, N. 1994. The fishes of the inland wa Zakaria-lsmail, M. 1994. Zoogeography and biodiversity of the fresh ters of Madagascar. ln Biological diversity in African fresh- and water fishes of south east Asia. Hydrobiologia 285:41-48.