Gymnapogonini Whitley 1941

Mabuchi, Kohji, Fraser, Thomas H., Song, Hayeun, Azuma, Yoichiro & Nishida, Mutsumi, 2014, Revision of the systematics of the cardinalfishes (Percomorpha: Apogonidae) based on molecular analyses and comparative reevaluation of morphological characters, Zootaxa 3846 (2), pp. 151-203 : 181-182

Tribe Gymnapogonini Whitley 1941

Type genus Gymnapogon Regan 1905

Diagnosis. Members of the Apogoninae : VI+I,8–13; anal fin II,8–16; head and body naked or with large weakly ctenoid or cycloid scales; lateral-line scales 23–24 or lateral line a series of free neuromasts to base of caudal fin, interrupted mid-line lateral line present or absent; preopercle ridge smooth, edge with one or more spines at angle; 0–2 ossified supraneurals; supramaxilla, paired uroneurals and basisphenoid absent; 2–3 epurals; hypurals 1–2 fused, 3–4 separate or fused to urostyle; parhypural separate or fused to hypurals 1–2; caudal fin forked or rounded; pterosphenoid and parasphenoid joined excluding prootic from internal orbit rim.

Other characteristics. one supernumerary dorsal-fin spine; unbranched or branched first segmented dorsal-fin ray, branched first anal-fin ray; cycloid or weakly ctenoid scales on predorsal, cheek, breast, two pelvic scales, and body; cycloid scale on opercle and onto base of caudal fin; pectoral-fin rays 10–14; 9+8 segmented principal caudal rays, 13–15 branched, upper one or two and lower one or two unbranched; unbranched procurrent rays, longest segmented; some enlarged teeth on premaxilla and dentary, canine or villiform on vomer, villiform on palatine; six infraorbitals, bony shelf on third infraorbital present or absent; 1–2 postcleithra; anterior ceratohyal smooth or notched; 10+14 or 9+15 ( Cercamia ) vertebrae; 7–8 ribs; 0–6 epipleurals; low crest on PU2.

Distribution. Pseudamiops East Africa to Japan, Hawaii and French Polynesia, Gymnapogon widespread from the Red Sea, East Africa to Japan and French Polynesia, Lachneratus from East Africa to Hawaii and Tonga and Cercamia from the Eastern Indian Ocean to Japan and French Polynesia.

Remarks. This tribe contains four genera, Cercamia , Gymnapogon , Lachneratus and Pseudamiops , corresponding to the clade I in the molecular trees ( Figs. 2–6 , Table 4 ). Species of the included genera are all translucent with many reductive morphologic characters. Although Pseudamiops was absent from the present analyses, we tentatively associated this genus with the Gymnapogonini based on its translucent body and the reductive morphological characters. Bergman (2004) noted: …"The cephalic lateralis system of Gymnapogon is very similar to that of Pseudamiops . A notable exception being that the preopercular and mandibular canal portions are confluent in Gymnapogon species. " Pseudamiops , with scales, lacks pored, notched or pitted lateral-line scales. Cercamia and Lachneratus have not previously been associated with Gymnapogon . Both genera have deciduous scales and both lack pored, notched or pitted lateral-line scales. Gymnapogon and Pseudamiops were formerly classified under Pseudamiinae , together with Pseudamia . As mentioned above in the remarks of the subfamily Pseudamiinae , the present molecular data significantly rejected their monophyly (H 14 in Table 6 ). In our molecular trees, two individuals of Cercamia cladara from two distantly distributed populations ( French Polynesia and Palau) were paraphyletic to Gymnapogon and genetically distant from each other, which may indicate needs of taxonomical revisions of them.

Tanaka (1915) described the new family Henicicthyidae for the new genus and single new species Henicichthys foraminosus . Tanaka's family name has been used only in the original publication. Whitley (1941) created the family Gymnapogonidae with Regan's genus as the type species. He noted that the oldest genus name '...becomes the root for the family name." Whitley's (1941) synonymy of the literature for Henicichthys has the last published use of this genus in 1939. Whitley (1941) recognized that Henicichthys foraminosus and Austalaphia annona Whitley 1936 are synonyms of Gymnapogon . The sole use of Gymnapogon has been continuous since 1941. Fowler (1944) and Lindberg (1971) used Gymnapogonidae . We regarded Gymnapogonini as an easily recognized tribal name among apogonids and is its preferred use.

Figures

FIGURE 2. Phylogenetic tree from the partitioned maximum-likelihood (ML) analysis. Numbers besides internal branches indicate bootstrap probabilities (BPs) from 1000 replicates (only those of> 50% shown). Species names of recent Ostorhinchus [we included here Apogonichthyoides melas as a possible Ostorhinchus, following Mabuchi et al. (2006)] were blue, those of Apogon sensu lato [genus Apogon in Fraser (1972)] excepting the Ostorhinchus red, and those of genus Rhabdamia in Fraser (1972) green. The names of the twelve major clades (clades I to XII) within the Apogoninae were indicated on the left of the corresponding clades. Four species, which phylogenetic positions were largely different among the ML, Bayesian (BA: Fig. 3), and most parsimonious (MP: Figs. 4 and 5) tress, were indicated by arrows with asterisks.

FIGURE 3. Phylogenetic tree (50% majority-rule consensus tree) from the partitioned Bayesian (BA) analysis. Numbers besides internal branches indicate Bayesian posterior probabilities (PPs: shown as percentages, only those of> 50% shown). Species names were colored as in Figure 2. The names of the twelve major clades were indicated as in Figure 2. Four species, which phylogenetic positions were largely different among the ML (Fig. 2), BA (Fig. 3), and most parsimonious (MP: Figs. 4 and 5) tress, were indicated by arrows with asterisks.

FIGURE 4. Strict consensus tree of two of the five most parsimonious (MP) trees (MP tree-A). Numbers besides internal branches indicate bootstrap probabilities (BPs) from 1000 replicates (only those of> 50% shown). Topological incongruity between the two MP trees denoted by an arrowhead. Four species, which phylogenetic positions were largely different among the ML (Fig. 2), BA (Fig. 3), and MP (Figs. 4 and 5) tress, were indicated by arrows with asterisks. Species names were colored as in Figure 2. The names of the twelve clades were indicated as in Figure 2.

FIGURE 5. Strict consensus tree of the remaining three of the five most parsimonious (MP) trees (MP tree-B). Topological incongruities between the three MP trees denoted by arrowheads. Four species, which phylogenetic positions were largely different among the ML (Fig. 2), BA (Fig. 3), and MP (Figs. 4 and 5) tress, were indicated by arrows with asterisks. This tree was largely different from the MP tree-A (Fig. 4) in the positions of Pterapogon kauderni and Vincentia novaehollandiae.

FIGURE 6. Strict consensus tree of the ML, BA and MP trees shown in Figures 2-5. Species names were colored as in Figures 2–5. The names of the twelve major clades (clades I to XII) within the Apogoninae were indicated besides the corresponding clades, while the names of the thirteen tribes (defined based on morphological characters) on the right of corresponding major and minor clades. The tribe Lepidamiini is not in the tree. Tribes with solid bars include species of Apogon sensu lato, and those with open bars do not include it. Geographic ranges were indicated on the right of the clades only for the species of clade II (Apogonini), all the other apogonids occurring on Indo-Pacific Basin. For the revised genus names of some species, see Appendix A.