Book review – The Banggai Cardinalfish
The Banggai Cardinalfish:
Natural History, Conservation and Culture of Pterapogon kauderni
Alejandro A. Vagelli
Wiley-Blackwell, John Wiley and Sons, Ltd. 2011, 224 pages
ISBN 978-0-470-65499-6 (Hardcover) $179.95
ISBN 978-1-1199-5036-3 (ebook) $149.99
There are three online excerpts at: http://www.wiley.com/WileyCDA/WileyTitle/productCd-0470654996.html, in addition to a brief description and table of contents of what is in the book.
Dr. Vagelli divided his treatise on the single species in Pterapogon into four parts: 1) a historical review of previous research, overview of the geography, ecology, and human activities of the Banggai archipelago; 2) an in-depth description of distribution, morphology, reproduction, ecology, and genetics followed by a review and hypotheses for systematics and evolution of Pterapogon including possible fresh-water origin of the Apogonidae; 3) conservation and regulation of the wild harvest of Pterapogon for sale in the world-wide aquarium trade; and 4) captive breeding and rearing of Pterapogon. Scientific knowledge of Pterapogon is mostly after the 1992 rediscovery – apart from the original description in 1933 and an osteological description in 1972 based on the type specimens. By 1998 scientists expressed concerns about threats of overfishing due to demands by the aquarium trade based on the known limited distribution of the species and its low spawning potential. The book contains significant information about other members of the Apogonidae in Part 2, but this is not indicated in the title or in the online descriptions.
Chapter 3 contains a geologic history of the Banggai Archipelago with 5 maps summarizing existing knowledge. The island complex inhabited by Pterapogon originated near New Guinea. This fact coupled with the analysis of known distribution and direct development of young leads the author to interesting hypotheses about vicariance of the species and evolution of the Apogonidae.
Chapter 5 describes the methods used to determine island distributions within the natural (native) geographic range (see map 3.2). Three island groups isolated by deep-water barriers were proposed. Known genetic information suggests that even small spatial distances of 2-5 km show genetic isolation (Chapter 9). Direct development, shallow water preferences and a body shape indicative of slower swimming ability all must play a role in reducing ability to disperse. The author concludes that the present fine scale native distribution was the result of localized colonization from sea level fluctuations and the species’ geographic distribution with respect to other apogonids was from geologic vicariance at least since the Oligocene. There has been a non-native range expansion of Pterapogon by human introductions, likely as part of the aquarium trade.
In Chapter 6 the author presents new information about the morphology of Pterapogon with some comparisons to other apogonids. His main intent is to provide morphological aspects useful in taxonomy, ecology and phylogenetic studies. Table 6.1 displays meristic characters with variation among the islands. For example, contrast specimens from Banggai and Seku for gill raker counts:
Upper Gill Rakers Lower Gill Rakers
8 9 10 25 26 27 28 29
Banggai 6 26 3 2 3 14 15 1
Seku 17 7 0 1 19 4 0 0
If the spot polymorphism is stable and variable across geographic populations (Chapter 9.3), then it may be likely that specimens from Banggai and Seku could be completely separated as if they were different species by mid-body spot pattern (Fig. 9.1) and gill raker counts. Add the genetic evidence, populations of Pterapogon may be acting like incipient species (reviewer’s observation).
Aspects of the reproduction of apogonids are discussed in Chapter 7 with a comprehensive table (7.1) summarizing 45 species in at least 12 (22 by newer information). There are significant gaps in available facts, but this work is an excellent place to start. Dr. Vagelli rightly questions reported cases of female egg brooding, internal fertilization and multiple egg ball brooding, all needing better documentation. Male brooding of the egg ball has been documented many times. Sexual dimorphism in apogonids appears to be confined to small species of Siphamia and temporarily to buccal cavity volume of male apogonids just before and during brooding the egg ball. A number of apogonids display temporary dichromatism during courtship, others do not. I know of at least one species, Ostorhinchus lateralis, with permanent dichromatism involving the presence or absence of a small spot on the side of the head. Other suspected examples involve the presence or absence of a black spot surrounding the genital area of a species of Cheilodipterus and a species of Ostorhinchus. Pterapogon has large eggs brooded by the male, exhibits no known dimorphism or dichromatism and is characterized by courtship and spawning taking place during the day.
There is a comprehensive section (7.2) on almost all aspects of the reproductive processes from courtship and spawning, the morphology and development of ova and sperm, early ontogeny of fertilized eggs and evidence for considering Pterapogon as having the lowest fecundity in the family. Morphological information did not extend to the micropyle, ridge pattern or filaments on the ova or eggs.
The estimated age and growth was from captive fish. The author inferred that in nature the maximum age was ~2.5-3 years. Batch spawning may occur at intervals of ~25 days (captive specimens) in adult females greater than 40 mm standard length year round. Female fish appear to choose a mate. Figure 7.3a-f depicts female egg ball extruding, spawning and transfer action by the male.
Habitat preferences and associations with living organisms begin chapter 8. The author missed a review article by J.E. Randall (2005) describing a number of cases of mimicry for apogonids. A complete description is given of three kinds of hosts, sea urchins, anemones and branching corals, that Pterapogon associates with during the day (color plates 8.1-8.3). Diet consisted mostly of harpacticoid, calanoid and cycloid copepods and other small crustaceans. Feeding begins at first light and ceases at dusk. Ectoparasites are briefly touched upon.
Systematics and evolution of Pterapogon and its nearest relative are in flux. The author discusses at length the evidence for direct development, bypassing larval stages, for Pterapogon, Glossamia, Quinca, and Vincentia. Species of the latter three genera are confined to the main Australian-New Guinea land mass. None has been found on intermediate islands between the Bird’s Head of New Guinea and the Banggai Island complex. The author sets up two hypotheses for the nearest living relatives: 1) Pterapogon is sister to Sphaeramia and 2) Pterapogon is sister to the only other genera known to have direct development. The first hypothesis gives no clue to whether the ancestor of Pterapogon originated before or after complete separation from the Australian-New Guinea land mass and may imply multiple origins/lineages for large eggs and direct development to juveniles. (The reviewer favors the first alternative that they are sister genera and both are sister to Eosphaeramia†, a well-preserved fossil about 50 million years old from Monte Bolca, Italy, based on shared morphologic characters.) The second hypothesis implies the ancestor existed on part of the Australia-New Guinea land mass and gave rise to three other genera with direct development the uniting factor. In the author’s scenario of freshwater origin of the Apogonidae, direct development would be basal, not a synapomorphy. Holapogon, mentioned only briefly, would support a marine origin of the family, having fewer specializations than Glossamia or Vincentia. Published partial molecular hypothetical trees to date for cardinalfish do not support, in part, either hypothesis. The author clearly admits “…the suggestion of an ancestral freshwater apogonid lineage is particularly speculative.”
Dr. Vagelli discusses some of the literature, pre-2010, about interrelationships among the Gobioidei, Kurtidae and Apogonidae. The search (section 10.5) for convincing morphological evidence to agree with partial molecular trees is not materially advanced with his review of literature. The idea that an ancestor to gobioids, kurtids and apogonids originated somewhere on the Australian-New Guinea landmass in freshwater is new.
Chapters 11 to 13 examine various aspects of the aquarium trade fishery for Banggai cardinalfish. The species is on the International Union for the Conservation of Nature’s Red List as endangered, but failed to obtain protection by the Convention on International Trade in Endangered Species. Chapter 14 on captive breeding probably is the best hope for blunting overexploitation of natural populations.
Undoubtably, there will be much more research associated with this unique apogonid. There is a very complete reference list and a well-documented index. I had no problems navigating around the book. There are a few typing errors, but they are not enough to be distracting. The online companion website did not work for me. The author is willing to send electronic figures and tables if the site is unavailable. It is a beautiful, pleasing book for those who collect fish books. The Banggai Cardinalfish will be a primary source for students, ichthyologists (molecular and morphologic), hobbyists and professional aquarists.
Literature Cited: Randall, J. E. 2005 Review of mimicry in marine fishes. Zoological Studies, 44 (3): 299-328, 124 figs.
Thomas H. Fraser
Florida Museum of Natural History,
University of Florida- Gainesville,
Florida 32611, USA