PHYLLOMEDUSINAE GÜNTHER, 1858

FAIVOVICH, JULIÁN, HADDAD, CÉLIO F. B., GARCIA, PAULO C. A., FROST, DARREL R., CAMPBELL, JONATHAN A. & WHEELER, WARD C., 2005, Systematic Review Of The Frog Family Hylidae, With Special Reference To Hylinae: Phylogenetic Analysis And Taxonomic Revision, Bulletin of the American Museum of Natural History 2005 (294), pp. 1-240 : 111-113

PHYLLOMEDUSINAE GÜNTHER, 1858

Phyllomedusidae Günther, 1858 . Type genus: Phyllomedusa Wagler, 1830 .

Pithecopinae B. Lutz, 1969. Type genus: Pithecopus Cope, 1866 .

DIAGNOSIS: The monophyly of this subfamily is supported by 95 transformations in nuclear and mitochondrial protein and ribosomal genes. See appendix 5 for a complete list of these molecular synapomorphies. A possible morphological synapomorphy is the pupil constricting to vertical ellipse (Duellman, 2001; known instance of homoplasy in Nyctimystes ). There are several larval character states that may be synapomorphies, such as: the ventrolateral position of the spiracle; arcus subocularis of larval chondrocranium with distinct lateral processes; ultralow suspensorium; secondary fenestrae parietales; and absence of a passage between ceratohyal and ceratobranchial I (Haas, 2003).

COMMENTS: Duellman (2001) considered the presence of a process on the medial surface of metacarpal II a synapomorphy of Phyllomedusinae , with a known instance of homoplasy in Centrolenidae . However, because Phyllomedusinae appears to be the sister taxon of Pelodryadinae, the situation is more complex. As noticed by Tyler and Davies (1978b), this character state is also present in some species groups of Litoria , so the internal topology of Pelodryadinae will determine whether this character state is indeed a synapomorphy of Phyllomedusinae , with homoplastic instances in Pelodryadinae, or if it is a synapomorphy of Phyllomedusinae 1 Pelodryadinae, with subsequent reversals in the latter taxon. The supplementary posterolateral elements of the m. intermandibularis have been considered a synapomorphy of Phyllomedusinae (Duellman, 2001; Tyler, 1971). As mentioned earlier, because it is more parsimonious to interpret the sole presence of supplementary elements of the m. intermandibularis as a synapomorphy of Pelodryadinae 1 Phyllomedusinae , at this point it is ambiguous which of the positions (apical as present in Pelodryadinae or posterolateral as in Phyllomedusinae ) is the plesiomorphic state of this clade.

The absence of the slip of the m. depressor mandibulae that originates from the dorsal fascia at the level of the m. dorsalis scapulae (which subsequently reverses in Hylomantis and Phyllomedusa , see below) could also be a synapomorphy of Phyllomedusinae ; however, its taxonomic distribution among nonphyllomedusines needs to be assessed. This is most needed in Pelodryadinae, where as far as we are aware, all observations on this muscle are limited to Starrett’s (1968) unpublished dissertation where she commented on its morphology in 2 of the 172 known valid species of the subfamily. Oviposition on leaves out of water could also be another synapomorphy of Phyllomedusinae , but this is dependent on the position of Phrynomedusa within Phyllomedusinae (species of this genus do not oviposit on leaves but on rock crevices or fallen trunks) and on the topology of Pelodryadinae (however, only two species of Pelodryadinae, Litoria iris and L. longirostris , are known to lay eggs out of water, and not necessarily on leaves; Tyler, 1963; McDonald and Storch, 1993).

Several transformations that resulted as synapomorphies of Phyllomedusinae in Burton’s (2004) analysis optimize ambiguously in our trees because their distribution is unknown in Cruziohyla new genus. Consequently, it is unclear which transformations are synapomorphic of the subfamily and which ones support the monophyly of internal clades. These transformations are: two insertions of the m. flexor digitorum brevis superficialis; the tendon of the m. flexor digitorum brevis superficialis divided along its length into a medial tendon, from which arise tendo superficialis IV and m. lumbricalis longus digiti V, and a lateral tendon from which arise tendo superficialis V and m. lumbricalis longus digiti IV; tendo superficialis pro digiti II arising from a deep, triangular muscle, which originates on the distal tarsal 2–3; tendo superficialis pro digiti III arising entirely from the margin of the aponeurosis plantaris; two tendons of insertion of m. lumbricalis longus digiti V arising from two equal muscle slips; pennate insertion of the lateral slip of the medial m. lumbricalis brevis digiti V; m. transversus metatarsus II broad, occupying the entire length of metatarsal II; m. transversus metatarsus III broad, occupying more than 75% of the length of metatarsal III; m. extensor brevis superficialis digiti III with two insertions, a flat tendon onto basal phalanx III and a pennate insertion on metatarsus III; and finally the m. extensor brevis superficialis digiti IV with a single origin with belly undivided. The presence of m. flexor teres hallucis is shared with Pelodryadinae; however, Burton (2004) stressed that in that subfamily, presence or absence of this muscle is subject to great intraspecific variation, without providing information as to the states present in the particular specimens he studied, so the character was scored as missing data in our matrix.

There are several other character systems that will likely provide additional synapomorphies for this group of frogs. Manzano and Lavilla (1995b) and Manzano (1997) described several unique character states from musculature, whose taxonomic distribution across all Phyllomedusinae needs to be assessed. Tyler and Davies (1978a) mentioned that Phyllomedusinae are the only hylids where the mandibular branch of the trigeminal nerve subdivides into two twigs after traversing the mandible. Various authors (e.g., Kenny; 1969; Cruz, 1982; Lescure et al., 1995) noticed that larvae of several species of Phyllomedusinae are usually suspended in water in an oblique or even vertical position relative to the water surface. Bagnara (1974) observed a light­sensitive tail­darkening reaction in larvae of two phyllomedusines ( Pachymedusa dacnicolor and Phyllomedusa trinitatis ), and we observed a similar reaction in tadpoles of Phyllomedusa tetraploidea (Faivovich, pers. obs.). Further research will determine how inclusive is the clade or clades supported by these synapomorphies.

The presence of multiple bioactive peptides has been suggested as a distinctive character of Phyllomedusinae (Cei, 1985) . Since the beginning of the biochemical prospecting, it has become evident that Phyllomedusinae have several different classes of bioactive peptides (Erspamer, 1994), some unique (e.g., sauvagine, deltorphins), some not (e.g., bombesins, caeruleins), as do the Pelodryadinae (Apponyi et al., 2004). Because there are multiple bioactive peptides, it seems reasonable to consider the different peptide families individually as potential synapomorphies of Phyllomedusinae , Pelodryadinae, or Phyllomedusinae 1 Pelodryadinae. More work needs to be done to better understand the taxonomic distribution of the different classes of peptides.