A new species and new distribution records for Braconidae from Mountain Lake Biological Station in southwestern Virginia and a redescription of Pentapleura foveolata Viereck
Author
Kula, Robert R.
text
Zootaxa
2013
3641
5
501
523
journal article
43619
10.11646/zootaxa.3641.5.1
8c4f5615-7ec8-41a5-8a62-4b8e0b3bf4f3
1175-5326
216777
26AEC7D3-F26F-4313-845C-7A199A9612FA
Braconidae
of Mountain Lake Biological Station
Seventy-four species of
Braconidae
are known from MLBS (Table 1). This includes 13 species from Milne and Milne (1944); only one of those species,
Austrozele uniformis
(Provancher)
, was collected through this research. The 14 species listed in Milne and Milne (1944) currently constitute 13 due to subsequent nomenclatural changes. The eight species in Milne and Milne (1944) identified to genus and listed as morphospecies only were not included in Table 1 because they were not available for comparison with specimens from this research. Seven hundred and forty-five specimens of
Braconidae
were collected through sampling carried out in this research and represented 62 of the 74 braconid species known from MLBS. Not included in Table 1 were
49 specimens
determined as Alysiini (n=3),
Chorebus
Haliday
(n=1),
Ephedrus
Haliday
(n=1),
Blacus
Nees
(n=1), and Microgastrinae (n=43) but not sorted into morphospecies because they are either males or damaged. Of the 62 species,
Alysiinae
and
Opiinae
were the two richest subfamilies, with 22 and nine species, respectively. Thus, at least 31 of the 62 species are parasitoids of cyclorrhaphous flies (Wharton 1997a, b).
Doryctinae
,
Aphidiinae
, and Microgastrinae were the next highest subfamilies in terms of richness, with six, five, and four species, respectively. Aphidiines are exclusively parasitoids of aphids (van Achterberg 1997a), doryctines are primarily parasitoids of wood-boring beetle larvae (Marsh 1997), and microgastrines are exclusively parasitoids of lepidopteran larvae (Whitfield 1997). The remaining 16 species represent nine subfamilies with no more than three species per subfamily. Six of those species are from the subfamilies Cheloninae (3), Macrocentrinae (2), and Orgilinae (1) and thus are parasitoids of lepidopterans (van Achterberg 1997b; Shaw 1997; Wharton 1997c). Considering those species along with the microgastrines, at least 10 of the 62 species are parasitoids of lepidopterans.
An undetermined species of
Dinotrema
Förster
was the most abundant (n=301) (Table 1) followed by an undetermined species of
Orthostigma
Ratzeburg
(n=113). Those two species alone accounted for 56% of the specimens collected through this research.
Cratospila neocirce
Wharton
(n=45) and an undetermined species of
Aspilota
Förster
(n=44) were also abundant relative to the other species collected. Species of
Aspilota
,
Dinotrema
, and
Orthostigma
are primarily parasitoids of flies in the family
Phoridae
, and their hosts are often associated with fungi (Wharton 1997a; Yu
et al.
2005). Given the high diversity of fungi at MLBS and its environs (Linder 1937; Meyer 1943; Graff 1947; Miller 1965), and at the sites sampled (especially Hunter’s Branch, R. Kula pers. obs.), it is likely that species of
Aspilota
,
Dinotrema
, and
Orthostigma
collected through this research attack phorids associated with fungi. Host use is unknown for species of
Cratospila
Förster
(Wharton 1997a; Yu
et al.
2005). No more than
17 specimens
were collected for any of the remaining species.
Specimens of
Spathius
Nees
from MLBS could not be identified reliably to species despite a recently published review that included a key to species in North
America
(Marsh & Strazanac 2009). Species are separated in couplet 3 of the key based on malar space length “at least 3/4 eye height” compared to “at most 1/2 eye height.” The malar space:eye height ratios for the two MLBS specimens considered a species near
Spathius calligaster
Matthews
are 0.55 and 0.48. They were taken through both options of couplet 3 and best fit the couplets following malar space length “at most 1/2 eye height.” Both specimens passed easily to couplet 8, where
Spathius longipetiolatus
Ashmead
was differentiated from other species of
Spathius
based on a “smooth and polished” scutellar disc. However, the scutellar disc transitions, anteriorly to posteriorly, from smooth to coriaceous in
S
.
longipetiolatus
based on examination of the
lectotype
and
paralectotype
. Therefore, other features must be used to differentiate
S
.
longipetiolatus
from congeners. The
lectotype
of
S
.
longipetiolatus
is missing the head and metasoma, and the wings and legs are damaged. The
paralectotype
is missing the wings and metasoma, and the rest of the specimen is damaged and covered with debris. This makes equivocal identification of
S
.
longipetiolatus
extremely difficult. The vertex of the
paralectotype
is almost entirely obscured but clearly strigate compared to entirely smooth in the MLBS
S
. sp. nr.
calligaster
specimens. Therefore, I do not consider them conspecific with
S
.
longipetiolatus
. If both specimens are keyed to couplet 9, they fit
S
.
calligaster
in that forewing 1CU and 2CU are interstitial; they differ in that t4 is smooth (“acinose” in
S
.
calligaster
per Marsh & Strazanac 2009), and the lateral margin of t2+t3 is sharp at the base only (“sharp and distinct” along entire length in
S
.
calligaster
per Marsh & Strazanac 2009). If both specimens are keyed to couplet 10, they differ from
Spathius evansi
Matthews
in that the vertex is smooth (strigate in
S
.
evansi
) and metatarsomere 3 is subequal to metatarsomere 5 (3 longer than
5 in
S
.
evansi
). They fit
Spathius elegans
Matthews
in that the vertex and t4 are smooth and metatarsomere 3 is subequal to metatarsomere 5; they differ in that 1CU and 2CU are interstitial (i.e., 2CU is intercepted by 2cu-a in
S
.
elegans
). Thus, the two MLBS specimens of
Spathius
considered a species near
S
.
calligaster
do not precisely fit
S
.
calligaster
,
S
.
elegans
, or
S
.
evansi
sensu Marsh and Strazanac (2009)
, but they fit closest to
S
.
calligaster
based on examination of primary and/or secondary
types
for the three species. Examination of
S
.
calligaster
paratypes
revealed that 1CU and 2CU are not interstitial (i.e., 2CU is intercepted by 2cu-a) and t4 is smooth in some specimens. Thus,
S
.
calligaster
sensu Marsh and Strazanac (2009)
differs from
S
.
calligaster
sensu Matthews (1970)
, although the former authors did not state this explicitly. The specimens of
Spathius
sp. nr.
calligaster
from MLBS key easily to the couplet containing
S
.
calligaster
in Matthews (1970). However, they do not have the head and mesosoma dorsoventrally compressed, and they lack a dorsal transverse swelling on the pronotum, features Matthews (1970) used to define
S
.
calligaster
.
Two other species of
Spathius
were collected at MLBS. Both key easily to couplet
16 in
Marsh and Strazanac (2009).
Spathius impus
Matthews
was differentiated at couplet 16 from other species of
Spathius
based on “ocellaroccipital distance equal to or less than ocellar-ocular distance” and “outer apical margin of hind tibia with 2–3 small spines.” The distance is longer in both species, but both have two spines on the outer apical margin of the hind tibia. Both species differ from
Spathius pallidus
Ashmead
(couplet 17) in terms of mesopleural sculpture and body color, and both species differ from
Spathius leiopleuron
Marsh and Strazanac
(couplet 18) in terms of mesopleural sculpture.
Spathius
sp. 1 fits
Spathius laflammei
Provancher
(couplet 18) except it has two spines on the outer apical margin of the hind tibia (
3–8 in
S
.
laflammei
).
Spathius
sp. 2 differs from
S. laflammei
in that the former has the vertex smooth (strigate in
S
.
laflammei
) and two spines on the outer apical margin of the hind tibia (
3–8 in
S
.
laflammei
).
Two specimens from MLBS were determined as a species near
Ontsira imperator
(Haliday)
. They differ from specimens in the USNM determined as
O
.
imperator
in that the MLBS specimens have the metafemur brownish yellow and the metatibia and metatarsus brown, while those features are entirely yellow in the USNM specimens. Also, the scutellar disc is rugose posteriorly in the MLBS specimens, while it is smooth with punctures in the USNM specimens.
One specimen from MLBS was determined as a species near
Diospilus fomitis
Mason. It
is similar to
D
.
fomitis
in that the ovipositor is downcurved apically. Conversely, the MLBS specimen has a sharply defined, pentagonal areola that bears a few rugosities, while the areola in four
paratypes
of
D
.
fomitis
in the USNM is either imperceptible (i.e., propodeum entirely areolate-rugose) or a weakly defined pentagon bearing areolate-rugose sculpture. Also, the head, mesosoma, and metasoma are darker brown in the MLBS specimen than in the
paratypes
of
D
.
fomitis
examined, and the metatibia and metatarsus are yellowish brown in the former compared to yellow in the latter. However, the lighter coloration observed in the
paratypes
could be an artifact of specimen preservation.
Fifteen species were reported from Virginia for the first time, but nine of those species are known from at least one state that borders Virginia. Noteworthy new distribution records are as follows (known distribution beyond Virginia in parentheses):
Aphaereta ithacensis
Fischer
(
CANADA
: Ontario;
U.S.A.
: Michigan, New York, Ohio [Fischer 1966]),
Pentapleura foveolata
Viereck
(
U.S.A.
: Connecticut [Viereck 1917]),
Tanycarpa gracilicornis
(Nees)
(Oriental and Palearctic regions [Yu
et al.
2005];
CANADA
: Alberta, Ontario;
U.S.A.
: Alaska [Wharton 1980]),
Ascogaster provancheri
Dalla Torre
(
U.S.A.
: Alaska, New Hampshire, New
Jersey
, New York, Ohio [Yu
et al.
2005]),
Euphoriella pallidifacia
Loan
and New (
CANADA
: Quebec [Loan & New 1972]), and
D
.
fomitis
(
CANADA
: Manitoba, Quebec, Saskatchewan [Mason 1968]). The specimens collected at MLBS are the southernmost records for those species.