Relicts from Tertiary Australasia: undescribed families and subfamilies of songbirds (Passeriformes) and their zoogeographic signal
Author
Schoddei, Richard
Author
Christidis, Les
text
Zootaxa
2014
2014-04-14
3786
5
501
522
journal article
5634
10.11646/zootaxa.3786.5.1
cdd39956-de72-43ea-afa3-cf79f805dd83
1175-5326
4913561
D2764982-F7D7-4922-BF3F-8314FE9FD869
Lamprolia
and
Chaetorhynchus
Lower montane New Guinean
Chaetorhynchus
(Papuan Silktail)
has conventionally been placed in the Old World family
Dicruridae
(drongos) and, with a square-tipped tail of 12, not 14 rectrices, considered “ancestral” in that family (
Mayr 1941
;
Vaurie 1949
,
1962
;
Rand & Gilliard 1967
;
Wolters 1979
;
Sibley & Monroe 1990
;
Dickinson 2003
;
Rocamora & Yeatman-Berthelot 2009
). The enigmatic Fijian
Lamprolia
(
Fiji
Silktail) has usually been placed with Australasian monarchs (
Monarchidae
) in recent classifications (
Pratt
et al
. 1987
;
Sibley & Monroe 1990
;
Dickinson 2003
;
Coates
et al
. 2006
), following
Olson (1980)
and DNA-DNA hybridization data in
Sibley & Ahlquist (1985)
.
Beecher (1953)
and
Harrison & Parker (1965)
referred
Lamprolia
to the Australo-Papuan malurid wrens (
Maluridae
) instead, whereas
Cottrell (1967)
and
Heather (1977)
even proposed affinities with the birds-ofparadise (
Paradisaeidae
). In response,
Wolters (1977)
placed it in its own family; and
Mayr (1986)
treated it as
incertae sedis
. In the two multilocus DNA sequence studies that have so far screened both,
Chaetorhynchus
and
Lamprolia
were recovered as sister genera with strong support (
Irestedt
et al
. 2008
;
Jønsson
et al
. 2011
). Moreover, both these studies and two more (
Norman
et al
. 2009b
; Nyǡri
et al.
2009) found this lineage to be sister to the Indo- Australasian fantails (
Rhipiduridae
), also with strong support, distant from drongos, monarchs and birds-ofparadise.
Morphological information is limited and non-committal. No specimen material of
Lamprolia
was available to us other than as photographic images. Moreover, the nest and eggs of
Chaetorhynchus
appear to be undescribed. Even so, indicative traits of
Chaetorhynchus
are as much or more rhipidurid as dicrurid. Its unguinal ridge along a basally broadened mandible, dense long rictal bristling arising from below as well as above the commissure of the bill, broad palatine shelf, simple zygomatic processes, and 12 rectrices are all rhipidurid. The tarsi of
Chaetorhynchus
, nevertheless, are short and thick as in drongos, not long and slender as in all fantails;
Lamprolia
has similarly short, thick tarsi and 12 rectrices.
Chaetorhynchus
also differs from both drongos and fantails in its narrowed sternum; the form of the sternum in
Lamprolia
may thus be informative.
Irestedt
et al
. (2008)
record no shared derived morphological traits that would link
Lamprolia
to
Chaetorhynchus
or the fantails exclusive of the monarchs (
cf
.
Olson 1980
). Yet despite a dearth of indicative morphological information, the corroborated DNA phylogenies resolve the phylogenetic position of these genera with reasonable certainty: they are based on comprehensive taxon sampling of 23 to 72 corvoid genera, use markers from two mitochondrial regions and four nuclear genes, and have robust support. DNA distances from
Rhipidura
are deep,
Jønsson
et al
. (2011)
dating the divergence at around the middle Oligocene. This may justify family ranking in the future, but we prefer a conservative approach at this stage and treat the
Chaetorhynchus
-
Lamprolia
group as a subfamily,
Lamproliinae
, in the
Rhipiduridae
(fantails) to indicate its phylogenetic affinities. Although
Wolters (1977)
used the name, he provided no description, leaving it a
nomen nudum
(Article 13.1 of the Code). The other subfamily, Rhipidurinae Sundevall, 1872, comprises the single genus
Rhipidura
.