Pelecanae II

The 44 Orders

Paleognaths

Galloanserae

Metaves

Pelecanae

Charadriae

Passerae

MUSOPHAGIFORMES

Musophagidae: Turacos

6 genera, 23 species HBW-4

Following Hacket et. al (2008), the turacos are considered sister to the Pelecanimorphae, although other positions are possible. The arrangement of the Turacos is based on a combination of Veron and Winney (2000) and Njabo and Sorenson (2009). Both use essentially the same data set (except for bannermani), but analyze it differently, with mostly the same results.

As in previous phylogenies of the turacos, there are three subfamilies: Corythaeolinae, Criniferinae, and Musophaginae. Corythaeolinae is monotypic. Musophaginae variously ends up sister to each of the others, so I treat this as an unresolved trichotomy. Within Criniferinae, Veron and Winney (2000) and Njabo and Sorenson (2009) found that the White-bellied Go-away-bird is sister to the rest. This demands a change of genus for it, in this case to Criniferoides (Roberts, 1926).

They also found that the Purple-crested and Ruwenzori Turacos are sister species, and basal in the Musophaginae subfamily. Veron and Winney (2000) also recommend placing them in the same genus. In that case Gallirex has priority.

For the rest, the tree here leaves two main naming options. One is to put them in one genus (Tuaraco). This does a poor job of reflecting phylogeny. The other option is the one followed here, using a more narrowly circumscribed Tuaraco. The name Menelikornis (von Boetticher 1947) applies to the White-cheeked Turaco, while Proturacus (Bates 1923) has priority for the Bannerman's Turaco group. Finally, given the difference in appearance between the two Musophaga and the Yellow-billed Turaco, I perfer to put the latter in a separate genus. It becomes Pseudopoetus (von Boetticher 1947).

Corythaeolinae: Great Blue Turaco

Criniferinae: Go-away-birds and Plantain-eaters

Musophaginae: Turacos

PELECANIMORPHAE

This brings us to the main subject of this page, the Pelecanimorphae. The Pelecanimorphae include 7 closely related orders: Gaviiformes (loons), Sphenisciformes (penguins), Procellariiformes (petrels and shearwaters), Ciconiiformes (storks). Pelecaniformes (pelicans, hamerkop, shoebill), Phalacrocoraciformes (frigatebirds, boobies, cormorants, darters), and Ardeiformes (herons and ibis).

There is a lot of support for grouping these birds together (e.g., Cracraft et al, 2004; Ericson et al., 2006a; Gibb et al., 2007; Morgan-Richards et al, 2008). The orders are arragned as in Hackett et al. (2008).

GAVIIFORMES

Gaviidae: Loons

1 genus, 5 species HBW-1

SPHENISCIFORMES

Spheniscidae: Penguins

6 genera, 19 species HBW-1

The penguin taxonomy follows Baker et al. (2006). Although the members of the pairs Macaroni/Royal and Snares/Fiordland are considered separate biological species, the pair Little/White-flippered are not. Christidis and Boles (2008) opined that it was premature to split them, and subsequent analysis have proven them correct. The complicated situation of the Little Penguin is analyzed in detail by Puecker et al. (2009), and I suspect it is not the last word on this. They found two clades, as did previous workers. However, they sampled many more penguins and found the clades did not divide as expected. In particular, there is no support for treating the White-flippered Penguin, Eudyptula minor albosignata as a separate species. Rather, there is a mostly Australian clade (with some New Zealand birds mostly from Otago and Omaru), and a clade covering the rest of New Zealand. Although most of the birds at Omaru seem to group with the Australian E. m. novaehollandiae, not all do. It appears likely that the type of E. m. minor, which is from Dusky Sound, belongs to the New Zealand clade. The significance of the presence of Australian clade birds at Otago/Omaru is yet to be fully understood. E.g., is there interbreeding? If so, how much? Although some uncertainty remains, it looks like two species are involved. The name Little Penguin has been official in Australia for some time, while Blue Penguin has been used in New Zealand, so it makes sense to call them Little Penguin, Eudyptula novaehollandiae, and Blue Penguin, Eudyptula minor.

The Macaroni/Royal and Snares/Fiordland pairs breed on different islands. The differences in appearance and DNA to are sufficent to allow treatment as separate species. In fact, the DNA difference seems to be less than between the Eudyptula clades (Baker et al., 2006), but the Eudyptula plumage differences are smaller and the situation on the breeding grounds is unclear.

Jouventin et al. (2006) make a good case for splitting Rockhopper Penguin into two biological species. I did not find the case for a three-way split compelling (Banks et al, 2006).

PROCELLARIIFORMES

Austin (1996), Austin et al. (2004), Kennedy and Page (2002) and Penhallurick and Wink (2004) were useful in organizing the Procellariiformes. Concerning the latter, the comments by Rheindt and Austin (2005) should be noted. Information concerning the Storm-Petrels and Gadfly Petrels was too ambiguous, so they follow Howard-Moore (except for the split of the Galapagos and Hawaiian Petrels).

Oceanitidae: Southern Storm-Petrels

6 genera, 8 species Not HBW Family

The split of the Storm-Petrels into two families was suggested by Nunn and Stanley (1998). See also Hackett et al. (2008).

Although it has not been fully confirmed, I've added the recently rediscovered New Zealand Storm-Petrel (see Gaskin and Baird, 2005). Details of the capture of one are on the Pterodroma Pelagics web site.

Diomedeidae: Albatrosses

4 genera, 21 species HBW-1

Robertson and Nunn (1998) suggested a radical new taxonomy for albatrosses, splitting them into 24 species. For the most part, this has been slowly been catching on and most of their splits are followed here. Part of the controversy is due to the fact that the genetic differences are fairly small for distinct species. However, these taxa are mostly separable in the field, and an increasing amount of evidence finds little gene flow between them—a sign of legitimate biological species.

Burg and Croxall (2004) provided support for most of the Robertson and Nunn splits in the Wandering Albatross group (except for D. antipodensis gibsoni), while Brug and Croxall (2001) examined the Black-browed/Gray-headed Albatross group. The Shy Albatrosses were studied by Abbott and Double (2003a, b).

The phylogeny used here is based on Nunn and Stanley (1998) and Chambers et al. (2009).

Hydrobatidae: Northern Storm-Petrels

4 genera, 17 species HBW-1

The Hydrobatidae have been rearranged based on Nunn and Stanley (1998) and Penhallurick and Wink (2004). This entails moving the Fork-tailed Storm-Petrel, Oceanodroma furcata, to the genus Hydrobates. Since O. furcata is the type species of Oceanodroma, it is helpful to give other genus names to the other three Hydrobatidae clades. Fortunately, the supply of available names is more than adequate. Those that are relevant are Cymochorea (Coues 1864, type leucorhoa) and Halocyptena (Coues 1864, type microsoma), and Thalobata (Matthews and Hallstrom 1943, type castro).

I've grouped melania and matsudairae together as they are sometimes considered conspecific. That pair is sister to the microsoma/tethys pair, and all join Halocyptena. I've also grouped two other possibly conspecific pairs, tristrami and markhami, and monorhis and leucorhoa. Homochroa might be close to the leucorhoa group. All of these go in Cymochorea. It's not clear where hornbyi goes, and it is provisionally placed somewhere in Cymochorea too.

That brings us to the basal group, the contentious Band-rumped (Madeiran) Storm-Petrel, Thalobata castro. Traditionally, it has been thought almost undifferentiated across the Atlantic and Pacific. Now we find that the genes reveal both substantial geographic and seasonal structure, enough that some recommend dividing it into a number of species (see Bolton (2007); Bolton et al., 2008; Friesen et al., 2007; Smith and Friesen, 2007; Smith et al., 2007).

In several locations, Band-rumped Storm-Petrel breeds in both the hot and cool seasons. Recent studies have found that the hot-season population is different from the cool-season population (e.g., Bolton, 2007; Frisen et al., 2007). The following table shows the island groups where Band-rumped Storm-Petrels breed, the season they breed, and applicable subspecific names. There may also be a population breeding on or near Sao Tome, but breeding sites have never been located. Further, it is unknown how closely the St. Helena and Ascension birds are related.

The breeding locations and seasons are:

Location Season Subspecies TiF Species
Ascension &
St. Helena Islands		 hot helena castro
Azores hot monteiroi monteiroi
Azores
Madeira
Canaries
Berlengas		 cool
both
cool
cool		 castro castro
Cape Verde Islands protracted
(cool)		 jabejabe jabejabe
Galapagos Islands both bangsi cryptoleucura
Hawaiian Islands hot cryptoleucura cryptoleucura
Japan hot kumagai cryptoleucura

Because they breed in the same location, there is a tendency to think of these as sympatric populations. Since they don't interbreed, they must be distinct species. QED.

Some have even suggested that castro be restricted to the birds breeding in Madiera (Desertas and Selvagem) during the hot season. The rest would be separated as Grant's Storm-Petrel, which does not yet have a scientific name. I find this hard to swallow. Based on Friesen et al. (2007) and Smith et al. (2007), the genetic distances appear to be quite small. Any separation between them is quite recent, perhaps within the Holocene.

Although Friesen et al. (2007) suggest the ancestral birds bred in the hot season, I don't really see this. The Cape Verde population is sister to the others and has a prolonged breeding season. If the ancestral population spread from there, one could easily see it adapting to local conditions that variously support breeding in the hot and/or cool seasons.

This suggests that considering them as sympatric gives the wrong impression. Rather, these populations occupy different niches that in some cases are separated temporally rather than geographically. They are better regarded as being adjacent (or even isolated) rather than overlapping.

This changes the picture. If we think of these populations as potential allospecies, they may not make the grade. There's not much differentiation. More evidence is needed, and there is more for some populations. Bolton (2007) used tape playback to explore whether there are pre-mating barriers to interbreeding. He investigated populations on the Cape Verde, Galapagos, and Azores islands. Although birds responded to calls of birds from their own islands, response to birds from other islands was weak and often no more than to unrelated control species.

This suggests that at least the subspecies tested — jabejabe (Cape Verde), bangsi (Galapagos), monteiroi (Azores hot season), and castro (Azores cold season only) — are distinct biological species. What about the other populations? We first consider the remaining Atlantic populations. Table 3 in Smith et al. (2007) addresses this issue. It shows that the northern Atlantic populations other than monteiroi are quite closely related (estimated divergence times from 100(!) to 17,000 years). Accordingly, I keep them all in T. castro. It also suggests that the birds from Ascension (and St. Helena?) are fairly close to the main populations of castro (divergence time 15,000-30,000 years, as opposed to about 100,000 years between monteiroi and castro, and 200,000-300,000 between jabejabe and either castro or monteiroi). Accordingly, I also treat helena as a form of T. castro.

That brings us to the Pacific populations. We start with the hot and cool season breeders at the Galapagos Islands. Bolton (2007) found they did not respond to the calls of band-rumped storm-petrels from the Atlantic. Moreover, Smith et al. (2007) found divergence times of over 200,000 years between them and the Atlantic breeders. Finally, Smith and Friesen (2007) found only weak evidence that these involve a cryptic species, and suggested they are only as distinct from each other as subspecies. Here they are treated as part of the same species, distinct from the Atlantic species. The analysis of Freisen et al. (2007) found that the Japanese and Galapagos breeders form a separate clade. Returning to Table 3 of Smith et al. (2007), we also see that the Hawaiian breeders belong in this group. Moreover, the divergence time of 150,000-200,000 years does not compel us to treat them as separate species from each other (absent further evidence). Accordingly, I treat the Pacific populations of band-rumped storm-petrels as a single species, T. cryptoleucura, including bangsi (Galapagos) and kumagai (Japan).

Click for Storm-Petrel tree
Click for Storm-Petrel tree

When all is said and done, I treat the band-rumped storm-petrels as 4 species. These species are separated not only by breeding location, but by whether they breed in the hot or cool season. In some cases there is little genetic differentiation between hot or cool season breeders, or across islands. When there is no other evidence they form separate species, those populations are lumped together, either as T. castro or T. cryptoleucura.

Pelecanoididae: Diving-Petrels

1 genus, 4 species HBW-1

Pelecanoididae tree The diving-petrels are traditionally considered a separate family from the petrels (Procellariidae). In many ways, including size, shape, and flight style, they are a southern counterpart of the smaller auks.

Procellariidae: Petrels, Shearwaters

15 genera, 84 species HBW-1

Click for Procellariidae tree
Click for Procellariidae tree

The relationships of the Pterodrominae remain somewhat murky, although the group from mollis to deserta is in decent shape. For now, I only show the genus Petrodroma on the tree. The taxa shown in brown are subspecies that may deserve species status.

Among the Petrodroma, I've elevated the Desertas Petrel, Pterodroma desertas to species status based on Zino et al. (2008) and Jesus et al. (2009).

Pterodrominae: Gadfly Petrels

Fulmarinae: Fulmars

Pachyptilinae: Prions

Procellariinae: Procellarine petrels

Puffininae: Shearwaters

The division of Puffinus into species is based on Austin et al. (2004). Since it is doubtful that the two clades of Puffinus (here called Ardenna and Puffinus) are more closer related to each other than to Calonectris, they are placed in separate genera.

The Calonectris shearwaters have been studied by Gómez-Díaz et al. (2006). They found that the three Atlantic taxa, borealis, diomedea, and edwardsii, form distinct clades that are roughly equidistant genetically, with diomedea perhaps closer to edwardsii. Their study of morphology found diomedea and borealis very close, with edwardsii somewhat more distant. I've treated this as an unresolved trichotomy on the tree (the brown taxa are subspecies that might deserve species status). The Atlantic taxa could be considered three species, in which case the Mediterranean population would take the name Scopoli's Shearwater, Calonectris diomedea while Cory's Shearwater would be Calonectris borealis. However, I'm a little uneasy about whether Cory's and Scopoli's are really that distinct, and prefer to leave them lumped together until I have more information.

The Cory's/Scopoli's split is of potential interest in the ABA area as there are several specimens of Scopoli's from New York in the early 20th century (Bull, 1974).

That brings us to the Puffinus species swamp. Although Austin et al. (2004) went a long way toward clarifying matters, not all of their results were conclusive, and an inability to extract DNA from certain specimens meant that some taxa were not included. There is a need for a multi-gene analysis.

In this taxonomy, they are grouped as follows. Christmas (nativitatis) and Galapagos (subalaris) form a basal group. Then, Hutton's (huttoni) and Fluttering (gavia) also group together. I've put Heinroth's (heinrothi) here, but am uncertain about where it really goes. All of these taxa are monotypic.

The rest of the Puffinus shearwaters are more tightly grouped, but divide into two parts. The Atlantic part includes Manx (puffinus), Yelkouan (yelkouan), and Balearic (mauretanicus) Shearwaters, which form a clade (again, are all monotypic). That clade is sister to the Little/Audubon's group. The southern Little Shearwater (assimilis), includes assimilis, tunneyi, kermadecensis, haurakiensis, and elegans. Arguably elegans should be raised to species level as Subantarctic Shearwater. The Audubon's group includes 4 taxa: Audubon's Shearwater (P. lherminieri lherminieri and P. l. loyemilleri (if valid)) and Macaronesian (P. baroli baroli and P. b. boydi). Of these, boydi may eventually be separated as Boyd's Shearwater. In both cases (elegans and boydi), the genetic data raises no objection. These both seem to represent monophyletic clades, and are sufficiently distinct genetically that they could be separate species.

The last group contains the rest. These birds breed in the Indian and Pacific Oceans, from the east coast of Africa to the west coast of the Americas. The second portion is relatively clear-cut. It includes the monotypic Black-vented (opisthomlelas) and Townsend's (auricularis) Shearwaters, together with Newell's Shearwater (newelli, plus myrtae). The 10 remaining taxa appear to be extremely closely related, enough so that they can all be placed in a single species, Tropical Shearwater, P. bailloni, as I do here. However, this species is sometimes split. Various suggested species are the monotypic Bannerman's Shearwater (bannermani), Persian Shearwater (persicus plus temptator), and Atoll Shearwater (dichrous, plus polynesiae, colstoni, and nicolae), leaving bailloni and the possibly redundant atrodorsalis in Tropical. I'm not sure which part gets P. b. gunax.

CICONIIFORMES

Hackett et al. (2008) found that the storks were basal in the remaining Pelecanae. Slikas (1997) did not come to a definitive conclusion on how to arranged the genera of the Ciconiidae. I've adopted her maximum likelihood tree. However, it may not be correct, and there were indications that Ciconia itself may not be monophyletic.

Ciconiidae: Storks

6 genera, 19 species HBW-1

PHALACROCORACIFORMES

The Phalacrocoraciformes were traditionally considered part of the Pelecaniformes (as were the tropicbirds). After all, how likely was it that such unusual features as a totipalmate foot and gular pouch would arise independently? They also share the location of the salt-excreting gland and all lack an incubation patch. These similarities lead Linneaus to put all but the tropicbirds (which lack the gular pouch) in the same genus.

It wasn't until the mid-20th century that ornithologists started to suspect that maybe these birds didn't all belong together. Hedges and Sibley (1994) used DNA hybridization to argue that not only did the pelicans and frigatebirds not belong with the group, but that the tropicbird also didn't belong.

In fact, their Figure 2 is quite interesting. If you try to map it onto the tree I'm using, you find that the tropicbirds are outside the Pelecanae entirely. More recent DNA analyses based on sequences usually put the frigatebirds (but not pelicans) in a group with the boobies, gannets, cormorants, and darters. We follow that here. Note that morphological support for this clade is not strong (Mayr, 2008).

Fregatidae: Frigatebirds

1 genus, 5 species HBW-1

The frigatebird taxonomy follows Kennedy and Spencer (2004).

Sulidae: Gannets, Boobies

3 genera, 10 species HBW-1

Click for Sulidae tree
Click for Sulidae tree

Sulid taxonomy follows Friesen et al. (2002). The extinct Tasman Booby, often considered a separate species, is here considered a subspecies of the Masked Booby following Christidis and Boles (2008). More recently, Steeves et al. (2010) provides strong evidence for this treatment. They further argue that Sula dactylatra tasmani is identical with the still extant subspecies S. d. fullagari, in which case both should be referred to as S. d. tasmani.

Anhingidae: Anhingas

1 genus, 4 species HBW-1

Phalacrocoracidae: Cormorants

2 genera, 41 species HBW-1

The arrangement below is based on the DNA analyses of Kennedy et al. (2000, 2001, 2009) and the osteological analysis of Siegel-Causey (1988). Where the studies overlap, there is considerable disagreement, and I have followed Kennedy et al. in these cases. You can click on the tree diagram for a hypothetical phylogeny. The species in black were included in Kennedy et al.'s analysis, while no DNA data is available for species marked in blue on the tree. In those cases, I've followed Sigel-Causey when possible. The placement of Bank Cormorant remains quite uncertain. The most recent effort by Kennedy et al. (2009) resolved the long-controversial status of the Flightless Cormorant. They found it is sister to the Neotropic and Double-crested Cormorants.

On the tree, I've included available genus names that could be used to subdivide Phalacrocorax. Unless they are generally adopted, they are perhaps best thought of as subgenera.

Although work has been done on the phylogeny of the blue-eyed shag complex, it remains murky. There are eight Phalacrocorax taxa involved: albiventer, atriceps, bransfieldensis, georgianus, melanogenis, nivalis, purpurascens, and verrucosus.

Following SACC, the King Cormorant, Phalacrocorax albiventer is considered a color morph of the Imperial Cormorant, Phalacrocorax atriceps (aka Blue-eyed Shag). Rasmussen (1991) makes a strong case. The key points are in the abstract: frequent hybridization and non-assortative mating in the contact zones. The genetic distance as measured using allozymes also seems very small.

However, Antarctic Shag, Phalacrocorax bransfieldensis and South Georgia Shag, Phalacrocorax georgianus are split off as separate species (Siegel-Causey and Lefevre, 1989). They present evidence that the breeding range of the Antarctic Shag formerly included the area around Tierra del Fuego, part of the breeding range of P. atriceps. They argue that there is no sign of interbreeding, indicating they are separate biological species. The South Georgia Shag seems more distinct, and is arguably also a separate species. These cluster together to the exclusion of the Kerguelen Shag in Siegel-Causey (1988), in which case it would also seem to be a separate species.

That still leaves 3 taxa to deal with. Unfortunately, there seems to be little solid information to work with. Christidis and Boles (2008) note all this, but consider these three taxa to be subspecies of P. atriceps. There is one piece of evidence. The genetic distance between purpurascens and albiventer is small enough for them to be a single species. However, it's also large enough to be different species. In HBW-1, Orta (1992) takes the opposite tack and splits them.

In version 2.17 I followed Christidis and Boles concerning melanogenis, nivalis, purpurascens. This left me with the same four species as Sibely and Monroe (1990). I gather I'm not the only one uncomfortable with that solution. It just doesn't make biogeographic sense to have birds breeding on the other side of the world lumped into atriceps when the physically closer taxa are considered separate species. In the absence of definitive information, this version follows Orta in considering them as three species, and presumes all three are closer to the Kerguelen Shag than to the Imperial Cormorant.

PELECANIFORMES

The status of two monotypic families, the Shoebill and the Hammerkop, has been a perennial issue. The analysis of Ericson et al. (2006a) indicates that both are relatives of the pelicans. Indeed, their tree allows them to be lumped into the same family. We keep them separate not only because of their uniqueness, but also because the division between them seems to be ancient.

Scopidae: Hammerkop

1 genus, 1 species HBW-1

Balaenicipitidae: Shoebill

1 genus, 1 species HBW-1

Pelecanidae: Pelicans

1 genus, 8 species HBW-1

ARDEIFORMES

Threskiornithidae: Ibises, Spoonbills

13 genera, 35 species HBW-1

Current thinking is that the extinct Reunion Solitaire was actually an ibis! Moreover, it seems to have been closely related to the sacred-ibises (see Mourer-Chauviré et al., 1995). Accordingly, it appears at the head of the ibis list.

Threskiornithinae: Ibises

Plataleinae: Spoonbills

Ardeidae: Herons, Egrets, Bitterns

20 genera, 67 species HBW-1

Ardeidae tree The Boat-billed Heron was previously considered to be the only member of the Cochlearidae, but is now just another heron. The list here is pieced together from the limited DNA evidence available (Chang et al., 2003; Sheldon et al., 2000) and more traditional morphological evidence.

The DNA evidence puts the tiger-herons first (only one was included), followed by the Boat-billed Heron. Then there is a group that includes Zebrilus, Botaurus and Ixobrychus. Chang et al. (2003) found the Black Bittern embedded in Ixobrychus. It's sometimes put in a monotypic genus Dupetor, which is here considered part of Ixobrychus.

It's not at all clear what happens with the night-herons. I've grouped them into a clade, but that has only weak genetic support. Still, the other options did not fare better.

The remaining genera mostly fall into two main clades. Butorides probably goes in one or the other, but the DNA is quite equivocal, so I put them in-between. I'm also guessing that Agamia is near Ardeola, but there's no DNA evidence, and the other evidence is pretty vague.

We consider the Ardea clade first. The Great Egret is sometimes put in a separate genus, Casmerodius. The 12S rRNA tree of Chang et al. puts them sister to the Intermediate Egret, and both sister to Ardea. Sheldon et al. (2000) didn't include the Intermediate Egret, but also found Casmerodius sister to Ardea. This is also why the Intermediate Egret is placed in Mesophoyx. Note that both of these are sometimes put in Egretta, but the DNA says no on this. The placement of Bubulcus follows both Chang et al. and Sheldon et al.

Following Kushlan and Hancock (2005) and Christidis and Boles (2008), I've treated the Great Egret as two species Casmerodius albus and Casmerodius modestus. There has been a reluctance to split them as the intervening populations have not been studied. However, the genetic distance between the two is quite large, comparable to that with Intermediate Egret (Sheldon, 1987). This suggest no significant gene flow between albus and modestus, that they are distinct biological species. In the absence of contrary evidence, it seems best to split them. Additional splitting of albus may eventually be needed, but that awaits further study.

The status of the Great White Heron, Ardea herodias occidentalis, remains controversial (e.g., Stevenson and Anderson, 1994). It is very near the borderline for species status. Genetically, it is nested within the larger Great Blue Heron clade. However, in their overlap zone in extreme south Florida, there seems to be little interbreeding between the dimorphic Great White Herons (the dark morph is sometimes called Würdemann's Heron) and the monomorphic Great Blue Herons (McGuire, 2002). Moreover, the Great Blue Herons of the Florida peninsula (wardii) are more closely related to those of the northern US (herodias) than to occidentalis. However wardii and herodias are closer to occidentalis than any of them are to fannini. For the present, I'm following AOU by treating them as one species although I'm not convinced this is correct.

The other group is the Ardeola-Egretta clade. Syrigma seems to belong here according to the DNA. That makes it natural to include Pilherodius too, but the relationships between all of these are unclear. As mentioned above, I'm guessing that Agamia belongs with this group, but there is not much to go on.

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