A further new genus of primitive phorid fly (Diptera: Phoridae) from Baltic Amber and its phylogenetic implications

2007·12.4 MB·English

by  Brian V Brown

A New
Further Genus oe Primitive Phorid Fey
(Diptera: Phoridae) erom Baetic Amber and
Its Phyeogenetic Impeications
Brian V. Brown^
ABSTRACT. Anewgenus andspecies ofprimitivephoridflypreserved in Baltic amber, Ulrichophora
lobata, is described. Itiscomparedtothe similarArchiphora robusta (Meunier) from Balticamberand
the extant Archiphora patagonica Schmitz, from which it differs most notably by the well-developed
anal lobe and the setation ofthe scutum. This latter character and its possible phylogenetic utility are
discussed in relation to other extinct and extant phorids. Further observations on the holotype of A.
robusta indicate that it is probably not congeneric with the extant A. patagonica (Schmitz), and A.
robusta is given the new generic name Hennigophora (new combination). A key to the Baltic amber
sciadocerines is given. A definition is given of a new, currently rankless group, Euphorida, which
includes all Phoridae except Sciadocerinae and Prioriphorinae.
INTRODUCTION incorrect, and that the three new specimens
represented a new taxon. The ramifications of
The primitive phorids classified in the subfamilies these observations are explored in this paper.
Sciadocerinae (formerly family Sciadoceridae;
Disney,2001) andPrioriphorinaeareafascinating METHODS AND MATERIALS
assemblage of mostly extinct forms with a pre-
viously unsuspected diversity. New discoveries of Amber specimens were examined and photographed
these primitive phorids have been made recently while immersed in heavy mineral oil. Scanning electron
(Mostovski, 1996, 1999; Arillo and Mostovski, micrographs (SEMs) of extant specimens were made
1999; Grimaldi and Gumming, 1999; Brown, with a Hitachi S-3000N SEM and standard coating
2002; Grimaldi et ah, 2002) from various pMroorcpedhubraens.kIm(awgwews.moofrpalhlbasnpke.cnimeetn)s.wSetrreucdteupraolsitteedrmisn
Mesozoic and Cenozoic amber deposits, and used are those of1. McAIpine (1981).
more are likely to be found (e.g., figures in
Grimaldi and Engel, 2005). In their structure, SYSTEMATICS
these flies bridge some of the gaps—between the
two extant species of sciadocerines Sciadocera Eamily Phoridae Curtis, 1833
rufomaculata White, 1916, from Australia and
New Zealand, and Archiphora patagonica Subfamily Sciadocerinae Schmitz, 1929
Schmitz, 1929, from Chile—and the other extant Ulrichophora new genus
species of the large family Phoridae. Their large
and increasingly better-known structural diversity DIAGNOSIS. Sciadocerinae. Scutum with
both provides information on the evolution of many setulae and few dorsocentral setae only;
these groups and confounds our understanding of lacking acrostichal setae (Pig. 1). Wing with well-
their history. developed anal lobe (Pigs. 4, 5). —
With the acquisition for study of three newly The other sciadocerine genera Archiphora
collected specimens of sciadocerines from late Schmitz, 1929, Eosciado—cera Hong, 1981, and
Eocene Baltic amber (Earsson, 1978), I began to Sciadocera White, 1916 differ in having scuta
review the structure of the oldest-known Baltic with well-developed, complete rows of dorsocen-
sciadocerine, Archiphora robusta (Meunier, tral and acrostichal setae, and in lacking random
1905). After close examination, I realized that setulae on the scutum.
there were some inaccuracies in Hennig’s (1964) TYPE SPECIES. Ulrichophora lobata new
redescription of this species, that some of the species.
supposed similarities with A. patagonica were
Ulrichophora lobata new species
Pigures 1-5
1. Entomology Section, Natural History Museum of DESCRIPTION. Body length 2.6-2.7 mm.
Los Angeles County, 900 Exposition Boulevard, Los Prons approximately one-third head width
Angeles, California 90007 USA. (Pig. 1); lacking medial furrow; with one pair
Email; [email protected] inner vertical, one pair ocellar, one pair reclinate
Contributions in Science, Number 513, pp. 1-14
Natural History Museum ofLos Angeles County, 2007
2 Contributions in Science, Number 513 Brown: New Genus ofPrimitive Phorid
Figure 1 Ulrichophora lobata new species, holotype male, head and thorax, dorsal. ABBREVIATION: dc -
dorsocentral setae
fronto-orbital setae near dorsal one-third, one apical one-third of femur; tibia with anterior seta
pair interfrontal setae near midlength. Complete near midlength. Tibiae without dorsal longitudi-
row of postocular setae present. One extremely nal setal palisades (found in many Phoridae);
long, curved genal seta present on posteroventral longitudinal setal palisades present on at least
margin of head (Fig. 2). Flagellomere 1 of fore- and hind tarsomere 1 (visible in holotype).
antenna elongate-oval (Figs. 1,2), slightlypointed Empodiumnotvisible,possiblyabsent. Wingasin
atapex, notgreatlyenlarged; arista slightly dorsal Figures 4 and 5; similar to that of extant
of apex. Palpus extremely small. Labellae of sciadocerines (Figs. 6, 7) except more elonMgate;
proboscis enlarged, expanded, bare (Fig. 2). costa extends nearly to wing tip; base of 1+2
Scutal disk dorsocentrally with small, even present; CuA2 present; numerous (about 20)
setulae; four posterior dorsocentral setae present, alularsetae present; anal lobe large; entire surface
anteriormost ofwhich is only slightly larger than of wing microtrichose. Venter of abdomen with
scutal setulae, second seta slightly larger, setae 3- well-developed setose sternites. Male terminalia
4 much larger (Fig. 1), rowconverging anteriorly; small, details difficult to observe, best seen on left
two intra-alar setae: one in anterior one-third side of holotype.
(which might belong to another row, being HOLOTYPE. (?, RUSSIA: Kaliningrad, Baltic
relatively ventral in position), the second in amber (catalog number LACM ENT 159890)
posteriorone-third; two posteriorsupra-alarsetae (Natural History Museum of Los Angeles Coun-
present; one large basal postpronotal setae pres- ty)-
ent; notopleuron with four long setae. Scutellum PARATYPES. S, GERMANY; Bitterfeld am-
with two pairs of large setae. Anepisternum ber (private collection Paulson); one specimen
without setae. Foretibia with one short antero- (sex indeterminate; specimen is largely obscured),
dorsal seta near apex; tarsomeres as in Figure 3. Baltic amber (Zoologisches Forschungsmuseum
Mid- and hind leg with anteroventral seta on A. Konig, Bonn).
Contributions in Science, Number 513 Brown: New Genus ofPrimitive Phorid 3
Figures 2-7 Sciadocerinae. 2-4. Ulrichophora lobata new species (Paulson specimen). 2. Head, left lateral. 3.
Foretarsomeres, lateral. 4. Right wing (photograph). 5. Right wing (drawing). 6. Archiphora patagonica Schmitz,
male, wing. 7. Sciadocera rufomaculata White, male, wing. ABBREVIATION: al - anal lobe
ETYMOLOGY. This name is in honor of Dr. the two extant species might not be monophyletic.
Hans Ulrich (Bonn), who kindly lent me his Afullrevisionofthesegroupsisoutsidethescopeof
specimen of U. lobata, and who has been highly thispaper,butfornow U. lobatacanbeclassifiedin
supportive of my phorid studies. a questionably monophyletic Sciadocerinae.
CLASSIFICATION. Relationships among the
primitive Phoridae are not well resolved. The IMPLICATIONS OF THE NEW GENUS
subfamily Sciadocerinae is only weakly supported
in most analyses (Brown, 1992; Grimaldi and The description of the new genus of sciadocerine
Gumming, 1999; Mostovski, 1999) and outside of phorid has implications for four subjects dis-
4 Contributions in Science, Number 513 Brown: New Genus ofPrimitive Phorid
cussed herein: the value of scutal setation in Schizophora (outgroup taxon) - Various states
phylogenetic reconstruction of the lower Cyclor- are found in this group, although a thorough
rhapha; status of the genus Archiphora; mono- review is beyond the scope of this paper. Some
phyly of the Sciadocerinae and Prioriphorinae; have random setulae and large marginal setae (as
and monophyly of a group within the Phoridae, inextantphorids); some have a singlemedianrow
exclusive of Sciadocerinae and Prioriphorinae. of acrostichal setae, as in some acalyptrates:
Leiomyza Macquart, 1835 (Asteiidae), Stenomi-
SETATION OF THE SCUTUM cra Coquillett, 1900 (Periscelididae), some Aula-
cigasterMacquart, 1835 (Aulacigastridae), Nemo
The setation ofthe scutum ofthe new species is of D. McAlpine, 1983 (Neminidae), Neomeoneur-
interest in relation to that of other phorids and ites Hennig, 1972 (Carnidae); many have two
related families. Specifically, the presence of acrostichal rows (for example in most calyp-
acrostichal and dorsocentral setal rows, and of trates).
scattered, random setulae, varies widely. The Chimeromyia Grimaldi and Cumming, 1999 -
evolution of these setation patterns was treated Thethree species ofthesestrange flieswereplaced
in a paper by Simpson et al. (1999), but this in the Eremoneura (Empidoidea + Cyclorrhapha),
treatment omitted detailed analysis of the lower although with family unknown, by Grimaldi and
cyclorrhaphan families =“Aschiza”), including Cumming (1999). There is a single median row of
(
phorids. acrostichal setae, plus the usual lateral rows of
The composition of the non-monophyletic dorsocentral setae; random setulae are apparently
lower Cyclorrhapha (whose status was reviewed absent.
by Yeates and Wiegmann, 1999) is controversial. Opetiidae - According to Chandler (2001:
Syrphidae and Pipunculidae appear to be more fig. 3) Opetia nigra Meigen, 1830, has random
closely related to the Schizophora than to other small setulae, no acrostichal setae, and larger
lower Cyclorrhapha, have random long scutal dorsocentral setae similar to those of U. lobata,
setae, and are not treated in further detail here. exceptthatthe dorsocentral rowismore complete
Opetiidae are questionably related to the Platy- anteriorly. There are about six differentiated
pezoidea (Collins and Wiegmann, 2002) and dorsocentral setae, of which the posterior two
might be basal to the entire Cyclorrhapha; are clearly larger.
furthermore, composition of the Platypezoidea is Platypezidae-The setae ofthe dorsumofmany
contentious (Cumming et ah, 1995; Collins and extant platypezids are organized into rows,
Wiegmann, 2002). sometimes with a single medial acrostichal row,
Hennig (1979) noted the tendency of Platype- a dorsocentral row, and fewer intra-alar and
zidae, Sciadoceridae and Phoridae to develop supra-alar setae (Fig. 8). The medial setae (acros-
a single median row of acrostichal setae, but tichal and most dorsocentral), however, are
cautioned that the direction of change from clearly smaller than the larger peripheral setae,
random setulae to single row of acrostichal setae and the acrostichal row is often absent (Fig. 9).
(or vice versa) was not established, and might Random setulae are absent.
have occurred more than once. An exception to the general conditions found in
States ofscutal setation for the various families platypezids is one possible fossil platypezid,
are reviewed below, with special emphasis on the Electrosania cretica (described by Grimaldi and
acrostichal and dorsocentral rows and on the Cumming, 1999), in which there are random
presence of random setulae. setulae, andinwhich dorsocentral and acrostichal
Asiloidea (outgroup taxon) - The Asiloidea, or rows are lacking. The placement ofthis species in
a portion therein, is considered to be the sister Platypezidae is controversial, however, as it has
group to the Eremoneura (Sinclair et ah, 1994). some unusually primitive characters.
There is a single median row of acrostichal setae Lonchopteridae - Extant species of this family,
in some genera in this group (for example, in at allofwhichareinthegenusLonchopteraMeigen,
least some species of the dasypogonine asilid 1803, lack random setulae, lack acrostichal setae,
genera Blepharepium Rondani, 1848, and Calli- and have relatively few, large dorsocentral setae
nicus Loew, 1872), some have differentiated (Fig. 10). Cretaceous fossil genera described by
dorsocentral setae, and some have scattered Grimaldi and Cumming (1999) apparently also
dorsal random setulae, with or without differen- have dorsocentral setae, but the full setation of
tiated dorsocentral setae. the scutum cannot be seen.
Empidoidea (outgroup taxon) - In the various Ironomyiidae -- There are three extant species
groups of Empididae and Dolichopodidae there of Ironomyia: I. nigromaculata White, 1916 and
are different types of scutal setation present: two undescribed species (D. McAlpine, in press).
random setulae without large dorsocentral and In a recent review of the group, D. McAlpine (in
acrostichal setae (as in some fossils illustrated by press) noted that these species displayed many to
Grimaldi and Cumming, 1999), one acrostichal no long, pilose dorsal setulae, and large marginal
row, and two acrostichal rows (Sinclair and setae only. In the Cretaceous fossil Cretonomyia
Cumming, 2006). pristina McAlpine, 1973, there are small
J.
Contributions in Science, Number 513 Brown: New Genus ofPrimitive Phorid 5
Figures 8-13 Scutum, SEMs. 8. Grossoseta pacifica (Kessel) (Platypezidae). 9. Polyporivora polypori (Willard)
(Platypezidae). 10. Lonchoptera sp. (Lonchopteridae). 11. Archiphora patagonica Schmitz (Sciadocerinae). 12.
Sciadocera mfomaculata White (Sciadocerinae). 13. Megaselia sp. (Phoridae). ABBREVIATIONS: ac - acrostichal
setal row, dc - dorsocentral setal row
random setulae, and few small marginal setae fossils classified in the Sciadoceridae (now Scia-
(J.
McAlpine, 1973). Other fossils occur (Mostovski, docerinae) and Prioriphorinae; the latteris a hold-
1995; Grimaldi and Gumming, 1999), but D. ing place erected by Mostovski (1996) for those
McAlpine (in press) had doubts that they were taxa that more closely resemble phorids. Fossil
related to Ironomyia and Cretonomyia; further- phorids have not always been documented in
more, he questioned whether this family was sufficient detail for this character.
related to the others considered here. Molecular Agaphora rara Mostovski, 1999-Accordingto
analysisshouldhelp answerthisquestion, anditis Mostovski (1999), there is a single median
unfortunate that the study of Collins and Wieg- acrostichal row and dorsocentral rows, but the
mann (2002) did not include a specimen of this setae are relatively small except for that on the
family. posteriormost dorsocentral aspect, which is twice
Cretaceous phorid fossils - There are many the length of the others. No mention is made of
taxa described inthe non-monophyletic morass of random setulae. The scutal setation of the other
6 Contributions in Science, Number 513 Brown: New Genus ofPrimitive Phorid
species in this genus, A. iunior Mostovski, is not Prioriphora spp. - The descriptions of P.
mentioned. longicostalis and P. setifemoralis by Brown and
Archiphora pria Grimaldi and Gumming, 1999 Pike (1990) noted that the scutal setation cannot
- The scutum of this species is obscured and be seen in these specimens.
cannot be reliably characterized. Sciadophora bostoni McAlpine and Martin,
Archisciada lebanensis Grimaldiand Gumming, 1966 - This species has long scutal setae,
1999-There arerandomsetulaeonthe scutumof organized in a single medial acrostichal row and
this species. two complete dorsocentral rows. No random
Euliphora grimaldii Arillo and Mostovski, setulae are present.
1999 - In their drawing (Arillo and Mostovski, This fossil was incorrectly listed as being
1999:fig. 2) and description of this species, the deposited in the Canadian National Collection
scutal setation is interpreted as setae in irregular in the original description (McAlpine and Martin,
rows, including a pair of acrostichal rows. The 1966). In fact, it was retained by the collector,
photograph ofthis species (Arillo and Mostovski, who subsequently sold it to the author. It is now
1999:fig. 1), however, showswhat Iconsider ran- deposited in the Los Angeles County Museum
dom setulae on the scutum, with larger marginal (LACM). In order to stabilize the fossil, it has
setae. been mounted in a block of clear epoxy.
Gemmaphora numerosa Mostovski, 1999 - Varya lalita Mostovski, 1999 - The original
According to Mostovski (1999), there is a median description (Mostovski, 1999) mentions well-
row of minute acrostichal setae (irregular anteri- developed dorsocentral setae, but no others.
orly), 12 dorsocentral setae, and random setulae. Myanmar amber phorid - The LACM collec-
Presumably, the random setulae are anterolateral, tion has one, as yet undetermined, specimen of
as in Archiphora patagonica (Fig. 11). phorid from Myanmar amber. It has wing
Maksika dvija Mostovski, 1999 - According to venation similar to that of specimens illustrated
Mostovski (1999), there is a single median row of by Grimaldi et al. (2002) as Prioriphora sp. This
acrostichal setae and a well-developed dorsocen- specimen has large marginal setae, plus random
tral row. No mention is made of random setulae. setulae, as in modern phorids.
Prioriphora canadambra McAlpine and Mar- Tertiary phorid fossils - Eosciadocera helodis
tin, 1966 -The original description ofthis species Hong, 1981 and E. setosa Brown, 2002 - These
depicts the scutum as having a platypezid-like two species have a single median acrostichal row,
setation, with a single median acrostichal row, well-developed dorsocentral and intra-alar rows,
andcomplete dorsocentral rows. Smaller setae are and are without random setulae.
depicted on the anterolateral corners only. Ryszard Szadziewski has an additional speci-
Prioriphora casei Grimaldi and Gumming, men of E. setosa in which he can see a well-
1999 - This species has random setulae on the developed empodium (R. Szadziewski, personal
scutum, similar to those of most extant phorids. communication). The lack of an empodium is
Prioriphora cheburashka Mostovski, 1999 - acharacterused byMcAlpine (1989) tojustifythe
According to Mostovski (1999), this species has family Sciadoceridae, but he noted that it is also
nine to 10 acrostichals in a single median row, absent in Lonchopteridae. Grimaldi and Gum-
nine to 10 dorsocentral setae, and random setulae ming (1999) used this character to define the
on the scutum. Sciadoceridae, exclusive oftheirfossilArchisciada
Prioriphora intermedia BrownandPike, 1990- lebanensis. Based on their analysis, Eosciadocera
This species has a single median acrostichal row, should also be excluded and placed near the base
and well-developed dorsocentral rows. No men- of their Sciadoceridae.
tion is made of random setulae (Brown and Pike, Archiphora robusta (Meunier) - I re-examined
1990). the holotype ofthis species (seefurtherdiscussion,
Prioriphora luzzi Grimaldi and Gumming, below). The scutum has three acrostical setae in
1999 - According to the description of this a single median row, and six dorsocentral setae.
species, there is a single median acrostical row, There are a few (|ewer than 10) smaller setae in
as well as a pair of paramedial acrostichal rows the anterolateral Corner, similar to those in A.
anteriorly, and scattered acrostichals. I have not patagonica^ P. canadambra., and S. rufomaculata.
seen a specimen of this species, and the thorax is Extant Sciadocerinae - These flies have well-
not figured, so the extent ofthe dorsocentral setae developed dorsal rows of setae, almost entirely
(which are briefly mentioned) is unknown. without setulae. In Sciadocera there is a single
Prioriphora polyankae Mostovski, 1996 - This median acrostichal row, two dorsocentral rows,
species has a single median acrostichal row of and two intra-alar setae (Fig. 12). In Archiphora
nine setae, plus a row of nine dorsocentral setae the acrostichalrowisrepresented bytwo (Fig. 11)
(with the posterior dorsocentral setae larger). to four setae only; otherwise it is similar to
Mostovski’s original description (Mostovski, Sciadocera.
1996) indicated that there were two acrostichal Extant phorids (except sciadocerines) - Most
rows, buthe latercorrectedthis error (Mostovski, have small even setulae on the dorsum of the
1999). There are no random setulae indicated. scutum, with larger setae mostly marginal in
Contributions in Science, Number 513 Brown: New Genus ofPrimitive Phorid 7
position (Fig. 13). Each setula is clearly socketed tending towards a single acrostichal row (Platy-
(Fig. 14). Some phorids have a few extra dorso- pezoidea) and another towards two rows (Schi-
central setae (e.g., Fig. 15), up to four in total zophora).
(Schmitz, 1938). Disney (2001) noted some Based on developmental evidence, itisprobable
phorids lack the small setulae of the thorax, but that the presence of two acrostichal setal rows is
this is likely a secondary loss at least in some a more primitive character state than having just
social insect-associated species {Platydipteron one row (P. Simpson, Cambridge University,
Borgmeier and Prado, 1975, Laishania Kung personal communication). The thorax is derived
and Brown, 2005). In Platydipteron balli Brown, from two physically separated imaginal discs, and
1994 (Fig. 16), for example, there are scattered the two halves of the adult notum fuse along the
large setae without the small setulae. Schmitz dorsal midline just before pupation when pre-
(1938) wrote that the scutal setae sometimes cursors for the bristles are already formed. Thus,
become bristlelike between the posterior dorso- there cannot be a single medianrowatthe time of
central setae, and more rarely along the median formationofbristle precursors. Simpson (personal
line, which he referred to as a single row of communication) assumes, but has not directly
acrostichal setae. Unfortunately, he did not name visualized, that a single row must arise from
any taxa with this character, so I could not movement ofthe precursors from a row on either
examine it, but it must be extremely rare. Some side that align to form a single one. Analagous
species of the genus Hypocera Lioy, 1864, have limited movement of precursors of microchaetes
a pair of marginal (posterior) setae medial to the =setulae of this paper, and which form rows in
(
usual dorsocentral setae that I (Brown and Buck, some Drosophilidae) has been shown to take
1998; Brown, 1999) named acrostichal setae. place in Drosophila (Renaud and Simpson, in
These are present only as a pair ofposterior setae press).
on the scutum, however, and do not form rows; Hennig (1979) stated that the direction of
probablytheyare anautapomorphic development evolution of scutal setation in the Phoridae
within these species. seemed to indicate that random setulae and no
In the phorid subfamily Termitoxeniinae some acrostichal row seems to have evolved from
minute species are without setulae on the scutum ancestorslackingrandomsetulaeandwithasingle
and instead have scattered (or poorly organized) median acrostichal row. The descriptions of
larger setae and no setulae (Fig. 17); however, Euliphora, Gemmaphora, Ulrichophora, and the
some larger termitoxeniine species have the usual Burmese phorid, however, shows that the situa-
random setulae and larger marginal setae. There tion is even more complicated, with some
are some molecular data linking termitoxeniines sciadocerine-like flies having the same characters
with the genera Dohrniphora Dahl, Diplonevra as the more derived extant phorids.
Lioy, and Thaumatoxena Breddin and Borner Ofthe families ofPlatypezoidea, nearlyall have
(Cook et ah, 2004), but in our preliminary some taxa with random setulae and some taxa
moleculardata (Brownand Smith, inpreparation) with a single median row of acrostichal setae; the
usingmanymoregenes and taxa, the same species exceptions are Lonchopteridae, which lack ran-
come out in a much different part ofthe tree. For dom setulae and acrostichal setae (contrary to
now I simply note the possibly primitive state Simpson et al. [1999] who stated all “Aschiza”
found in this group. have species with random setulae), and Irono-
myiidae, which lack dorsocentral and acrostichal
SUMMARY OF SCUTAL SETAE setae; possibly Platypezidae should be added to
IN CYCLORRHAPHA this list, depending on the classification of
Electrosania. Where the presence or absence of
Based on this review of the scutal setae of lower random setulae or acrostichal setae is derived or
Cyclorrhapha, it is possible to generalize (as did primitive is not yet known, but the presence of
Hennig, 1979, and Sinclair and Cumming, 2006) random setulae and acrostichal setal rows seems
that a single acrostichal row, or the tendency to to be mutually exclusive. Further research is
develop such a row, is primitively present in needed, incorporating these and other characters
Platypezoidea (based on its presence in Sciadocer- into phylogenetic analyses.
inae, some Prioriphorinae, and some Platypezi-
dae) althoughitisabsentinsometaxa (Opetiidae, IMPLICATIONS FOR GENUS
Lonchopteridae, Ironomyiidae, most Phoridae). ARCHIPHORA SCHMITZ
Thepresenceofa singlerowofacrostichalsetae
is incontrast to the paired acrostichal setae found Hennig (1964) placed Meunier’s Napomyza
in many Schizophora, although a single row is robusta in the genus Archiphora based on two
found in some schizophoran taxa. Thus, the characters: the reduced anal lobe (which he
conclusion of Simpson et al. (1999:p. 1354) that referred to as axillary lobe or “axillarlappen”),
the pattern for Cyclorrhapha was set in the and the reduced cell cup =anal cell).
(
common ancestor of the group is not entirely The anal lobe is indeed reduced in both
correct, as there was apparently one group Archiphora patagonica and A. robusta. By itself.
8 Contributions in Science, Number 513 Brown: New Genus ofPrimitive Phorid
Figures 14-17 Phoridae, scutum, scanning electron micrographs. 14. Megaselia sp. (higher magnification). 15.
Spiniphora maculata (Meigen). 16. Platydipteron balli Brown. 17. Termitophilomyia zinibraunsi Disney
however, it is a relatively weak synapomorphy of Archiphora patagonica and A. robusta being
thegenus; suchreductionoccurs inmanytaxa and congeneric. A synapomorphic character state of
is widespread in Phoridae. The wing of the two the twoextantsciadocerines,A. patagonica andS.
species is similar in shape (short, rounded), rufomaculata, is that flagellomere 1 of males is
another possible character linking them, although greatly enlarged (although this character also
one that might be functionally linked to the occurs widely in the Phoridae), with a coincident
reduced anal lobe. reduction in the length ofthe frons and the loss of
The reduction ofcell cup is not a valid synapo- the interfrontal seta. In the single specimen of A.
morphy of Archiphora. A comparison of a wing robusta, flagellomere 1 is small, the frons is long,
photograph of a male A. patagonica (Fig. 6) with and the interfrontal seta is present (Hennig,
that of a male Sciadocera rufomaculata (Fig. 7) 1964:fig. 10).
shows that this cell is equivalent in the two extant In both extant species, A. patagonica and S.
species.Inmyre-examinationofthespecimenofA. rufomaculata, the common base ofwingveins Mi
M
robusta I was able to obtain a different view from and 2 is reduced (Figs. 6, 7); in S. rufomaculata
Hennig’s(1964:fig. 5) drawing,andfoundthatcell it is virtually absent. This is another potential
cup is much larger (see Fig. 18) than portrayed in synapomorphic character of the two species. In
Hennig’sfigure. Thischaracteristhus shownto be contrast, the medial base in A. robusta is
completely spurious. apparently well developed. Therefore, recognition
Hennig (1964) declared the specimen of Archi- of A. robusta as part of genus Archiphora would
phora robustato be a female. Inmyopinionthis is render the genus paraphyletic (Fig. 24).
incorrect; the terminalia are indeed small, but Withlimitedevidence to linkA. patagonica and
they are also small in males ofA. patagonica and A. robusta, and noting the possible synapo-
Sciadocera rufomaculata. Furthermore, in ventral morphic characters of A. patagonica and S.
view details are visible that show the specimen is rufomaculata, I propose a new genus name
a male, particularly the presence of large, median Hennigophora to include the type species H.
cereal lobes and epandrium- and surstylus-like robusta (Meunier) (new combination). Diagnosis
sclerites (Fig. 19). ofthis taxon is as follows: male with flagellomere
The determination that the specimen of A. 1 relativelysmall; frons large,withfrontalsetaeas
robusta is a male greatly undermines the case for in Archiphora patagonica (Fig. 21); scutum with
.
Contributions in Science, Number 513 Brown: New Genus ofPrimitive Phorid 9
18
Figures 18-19 Hennigophora robusta (Meunier). 18. Base ofwing. 19. Male terminalia, left lateral
well-developed rows of setae consisting of one acters that are not visible in fossils. One of the
median acrostichal row and one dorsocentral row other two characters, the enlarged male flagello-
M
on each side; base of Mj + 2 well developed; meres, apparently applies only to the extant
anal lobe small; empodium absent; male termina- species of the subfamily, as discussed above. The
lia with separate surstylus on left side. onlyremainingcharacteristhe asymmetrical male
In order to clarify the recognition of the Baltic terminalia, a condition that is also widespread in
sciadocerines, I present the following key to many Phoridae and that is difficult to observe in
species: amber fossils. This lastcharacterwas also the one
used to define Sciadoceridae by Grimaldi and
KEY TO BALTIC AMBER Cumming (1999) in their phylogeny.
EOSSIL SCIADOCERINAE Disney (1991) proposed that the presence of
enlarged anterior femoral setae on the mid- and
1. Scutum with small random setulae and only hind legs as a synapomorphy of Sciadocerinae (as
a few large dorsocentral setae (Fig. 1) Sciadoceridae), and they are indeed present in
Ulrichophora lobata n. sp. Sciadocera, Archiphora, Eosdadocera, Hennigo-
Scutum lackingrandom setulae, butwith rows phora, and Ulrichophora. They also occur in
of large dorsocentral and acrostichal setae (as Lonchoptera, however, and in some Prioriphor-
in Figs. 11, 12) 2 inae: onthe midfemurofmostPrioriphora (except
2. Frons narrow, about one-quarter head width; P. intermedia Brown and Pike, 1990) and also the
scutellum with 10-12 setae hind femur of P. setifemoralis Brown and Pike,
Eosdadocera setosa Brown 1990. The midfemoral seta is present in Archis-
Frons broader, about one-half head width; dada, but the seta is absent from the hind femur.
scutellum with 4 setae Unfortunately, the terminalia of Prioriphora fos-
Hennigophora robusta (Meunier) sils arenoteasilyvisible, and itisimpossible totell
A further species of Archiphora, A. pria, was whether they are asymmetrical or not. It is
described from Cretaceous New Jersey amber possible that the presence of an anterior seta on
(Grimaldi and Cumming, 1999). This species has the midfemur could be used to group Prioriphora
a well-developed base of vein M, unlike A. with Sciadocerinae, but this would contradict
patagonica and Sciadocera rufomaculata; has some other hypothesized apomorphies. Further
numerous frontal setae; has a scutum possibly research is required, and it would be especially
with random setulae and apparently has no important to examine further specimens.
medial macrosetae (although the scutum is Basing the monophyly ofthe subfamily Sciado-
obscured). It probably should be placed in cerinae on the asymmetrical terminalia, an often
another genus. convergent and difficult-to-observe character, is
tenuous and unsatisfactory. It is possible that this
MONOPHYLY OF SCIADOCERINAE “subfamily” is part ofa paraphyletic stem group,
AND PRIORIPHORINAE in which the fork of the radial veiMns is still
extremely long and the base of Mi -h 2 is still
Sciadocerinae-Isupportedthe monophylyofthis present (although reduced in Archiphora patago-
group (Brown, 1992) in my revision of phorid nica and absent in Sciadocera rufomaculata)
classification with some hesitation. Of the four Alternate views are those of Mostovski (1999)
characters I proposed, two were internal char- and Disney (e.g., 2001). Mostovski (1999)
10 Contributions in Science, Number 513 Brown: New Genus ofPrimitive Phorid
fronto-orbital
ocellar
innervertical
20
21
9 Sciadocera
rufomaculata 9 Archiphora
patagonica
ocellar
fronto-orbital
y
22 23
9Agathomyia sp. 9 Lonchoptera
bifurcata
Figures 20-23 Platypezoidea, heads
attempted to justify the Sciadocerinae by the based on the absence of an empodium, a char-
presence ofa poorly developed anal lobe, but also acter that also occurs in some Sciadocerinae.
noted that both states were present in this group. One described species, Euliphora grimaldii, was
This character is further undermined with the classified as a prioriphorine by its authors
inclusion of U. lobata, with its large anal lobe, in (Arillo and Mostovski, 1999) in spite of its
the Sciadocerinae. Disney (1985 and elsewhere) having an empodium. Given that some prior-
maintainsthatthe long, thinveinsofmostphorids iphorines seem to be more similar to extant
are different from those in the sciadocerines, phorids (minus sciadocerines) than others, there
based on some mutants with unusual cross-veins is evidence that it is instead a grade group. It
that point to differing vein homologies. My was considered a grade, or paraphyletic group,
disagreement with Disney’s hypothesis was out- by McAlpine and Martin (1966), Brown (1992),
lined previously (Brown, 1992). and Grimaldi and Gumming (1999:fig. 65). See
Prioriphorinae - Mostovski (1999) proposed also the discussion of Gemmaphora numerosa,
that the Prioriphorinae were monophyletic. below.