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942BIML Update - Nomada, Sphex, Lasioglossum, Perdita, Mystery Map

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  • Sam Droege
    Feb 2, 2010
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      Nomada fragariae and N. lehighensis.  Molly Rightmyer, Cory Sheffield, and Sean Brady's  DNA work has identified the missing sexes for these species and helped clarify their descriptions...We would be very interested in looking at any additional specimens of either species.


      Nomada fragariae Mitchell

      Nomada fragariae Mitchell 1962: 391 [NMNH on indefinite loan from NC State? (male) label data: ]
       
      Diagnosis.  

      Females - (A more complete description coming)Described here for the first time.  Unique among other species of Nomada with complete bands of yellow on their tergites in that the rear face of the propodeum has absolutely no hair, the other species have copious, long hair on the segment.  There are 4-6 hind tibial setae, these are long, and approximately the length of the surrounding white hairs, curved outward not over toward the side like N. luteoloides or N. imbricata.  In comparison with the other species the microscopic projecting hairs on the underside of the antennae (not the appressed minute ones) on the surface are clearly longer.

       
      Males -  Unique among similar looking species (e.g., N. luteoloides, N. imbricatea, N. annulata) in that the very apex of the upper, and much lighter colored, surface of the last segment of the antennae lies near the centerline of the segment or slightly shifted towards the outside of that imaginary medial line; additionally there are 3-7 setae that project out from that surface beyond the tip that, while microscopic, are distinct under high power and much larger than the small, appressed hairs that dot the surface, in other species the apex is shifted nearly to the outside edge of the antennae, although less extremely so in N. sulphurata, and there are no setae projecting beyond its tip. The entire sides of the scutum usually with a narrow, but sometimes faint, border of yellow. Only N. imbricata also has yellow on the scutum and this is usually, but not always, restricted to the sides of the scutum to the rear of the tegulae, rarely does it run the entire segment, the rest of the similar species have no yellow on the scutum. The scutellum has but one broad band of yellow in all specimens unlike the common occurrence of 2 independent round yellow circles in similar species.  Length of flagellar segment 1 variable, but usually about half of 2.   On the rear leg, the tibial setae number 4-8 and are usually difficult to detect as they blend into the hairs behind them, but are unique in that they are evenly spaced out and follow the rim itself and are usually just a bit longer than the surrounding white hairs.  The yellow on rear face of propodeum can vary from 0 (rare) to 3 separate sets of patches, usually there is one set above the hind coxae, one on the sides of the propodeal triangle, and then often a fainter one in between.  The small round mound at the top of the mesepisturnum usually with a very faint yellow mark.  A yellow stripe in the center of the mesepisturnum runs from the front towards the rear. The upper surface of the antennae yellow-brown.
       
      Material examined. -  60 specimens examined from MD, NC, GA. 

      Molecular results. - 
       

      Variation. - In the males, the yellow band on the first tergite varies widely from complete to restricted or even broken in the center.  Most individuals have complete bands of yellow in the remaining segments, however, in a few individuals the band on T2 is restricted in the center and in a few completely broken.  All the males examined had a thin, lateral, border of yellow on the otherwise black scutum, though in a few it did not run to the anterior edge.  The amount of yellow on the rear face of the propodeum varies from none to the diagnostic pattern mentioned in the Diagnosis section.  Females did not demonstrate any significant variation in morphology or coloration.
       

      Discussion. -  This is truly an uncommon species, surely the female would have been noticed prior to now by past taxonomists given its unique visual presentation.  Hosts have not been mentioned in the past and we have gathered no direct evidence either, however, most of the specimens from Calvert County came from a month long project run the USDA's parasitic Hymenoptera group who were investigating color preferences in bowl traps for their wasp groups.  Droege looked at the approximately 8600 bee specimens collected and the only Andrena species that came close to matching the distribution of captures of this Nomada were A. confederata and A. violae.  Andrena confederata was the only common large species of Andrena present on the site (18 species were recorded).  Andrena violae is of moderate size and very common in Mid-Atlantic lawns and fields where violets are present.  It would appear unlikely that A. violae were the host as many more specimens of N. fragariae presumably would have been captured in the past throughout A. violae's range.  Range-wide A. confederata is uncommon and has a largely southern distribution, matching fairly well the known specimens of N. fragariae.  Andrena confederata is known from the Midwest but it appears to be even less common there and no known N. fragariae specimens from that region have yet to appear.

       
      Nomada lehighensis Cockerell

      Nomada lehighensis Cockerell 1903: 605 [ANSP (female) label data:  "Lehigh Gap, Pa. 7.1.97 // (female symbol)// P43// Type No. 10147 [red label]//N. lehighensis Ckll Type"]
      Nomada kingstonensis Mitchell 1962: 420 [NMNH (female) label data: ] new synonymy
        
       
      Diagnosis.

      Females. - In general aspect similar to and likely to be confused with the group of Nomada possessing thin white to reddish setae on the apical ends of their hind tibiae (e.g., N. pygmaea, N. sayi, N. illinoensis).  In contrast, N. leghighensis has 2-4 (typically 3) very stout, dark red setae that are evenly spaced along the margin of the apical end of the hind tibia and do not project beyond the surrounding white hairs.  As with many species, there is a single long thin setae between the stout setae and the short triangular projection that nearly all Nomada have along the apical end of the rear tibiae.  In combination with the setae the pattern of yellow markings on the abdomen is usually diagnostic.  In a few specimens there are no markings whatsoever, however, in the majority there are some very small yellow dots (at times minute) on the very far sides of T2-5, far to the sides, so far on the sides, in fact, that they are often not visible from above.  Progressing from specimens with very few markings to those the most heavily marked the markings appear on the tergites in the order from T2, T3, T5, T4.  These markings will increase slightly in size with more heavily marked individuals, however, as the extent of the markings increase they progress to increases in the center of T5 forming a rectangular spot of yellow, next a latitudinally linear set of markings or band (not joining with the maculations on the far side and usually absent in the center), and then T3 will have a set of additional submedial round spots similar in size to, but not conjoined with, the yellow dots on the far sides.   We have not seen markings on T2 other than the small ones on the far sides.  Unlike many species the scutellum is pillow shaped, lacking a median depressed longitudinal crease or valley. In comparison, the pseudopygidial area is usually more extensive than in other similar species, invading the interior of T5 to a greater extent and containing relatively long and coarse hairs.  The rim of the gena tends to be slightly rolled or bent outward, interrupting the smooth convex curve of the rest of the segment.  

       
       
      Males. - Described here for the first time. (Complete description to come).   Only 2 males were available from the barcoding work, and despite the large geographic distance, they are very similar in morphology and coloration.  Similar to the females, the initial impression would be of a species from the group N. sayi, N. illinoesnsis, N. pygmaea, etc group.  Both the head and the thorax are largely black with no yellow markings on the mesepisturnum, propodeum, or scutum.  One individual has small yellow markings on the pronotal collar, the other has 2 large red circles on the scutellum.  Distinctive are the 2-4 large setae along the rim of the apical end of the rear tibiae.  As with most male Nomada these are not quite as large and tend toward translucent, making them a bit more difficult to see.   The abdominal yellow markings are more extensive that the females but continue the general pattern.  One specimen has minute yellow markings on the far sides on T1, T2-4 having yellow markings, but these and those on the rest of the segments at times blending into a dark orange background color making it difficult to discern boundaries, thus making it difficult to determine the pattern of these bands of color and these bands could be quantified as both complete and broken in the center.  T3 and T4 appear to have 2 sets of lateral markings one on the extreme sides (similar to the females) and another a bit more to the interior. T6 has vague, dark orangish/yellowish markings that are difficult to classify.  
       
      Distribution. - A largely northern species that likely is tolerably common, but under-reported due to confusion with other species.  We have seen specimens from the Maritimes to British Coumbia and south in the mountains.  In the East the species ranges as far south as the Smokies and specimens have been collected from the Fall Line in the Washington D.C. area, but not on the Coastal Plain. 

      Material examined. - See spreadsheet

      Molecular results. -

       
      Variation. -  The extent of yellow markings on the abdomen varies in both males and females.   For the females we have seen a relatively long series and specimens and markings can vary from none to modest amounts on all the segments except T1 which in all cases lacks color.  See the description for further details.   The amount of black on the scutum varies from only a small section along the medial anterior edge of the plate, to black stripes running longitudinally along the sides, medially, and progressing to additional black stripes between those two areas.  Similarly, and usually corresponding to the degree of black in the scutum, the amount of black in the face varies from a small patch surrounding the ocelli to a large coalesced patch surrounding both the ocelli and the antennal bases.  The variation in the males is based only on 2 individuals and those are listed in the descriptions above.  Based on experiences with similar species, most males will likely be dark, but it wouldn't be surprising if extensive amounts of red showed up in some populations, particularly in the Southern Appalachians.
       
      Discussion. -  As already mentioned, this species is likely under-reported due to its similar appearance to other common species.  The identity and separation of all these species has been confused in the past, so it is also not surprising that the male had yet to be described.  The sparse number of stout setae on the hind tibiae is key to determining this species.  Mitchell's N. kingstonensis was described from only a single female and is synonymized here.  The holotype is faded and thus it is difficult to easily discern all the markings, however, it appears to have the small distinct yellow marks on the far sides of T2 and does have the appropriate patterns of hind setae, slightly reflexed rim of the gena, and the general pattern of black markings that N. lehighensis has. 
       
       
      The following has been added to the Sphecidae guide to better discriminate these 3 Sphex species.

      S. dorsalis, S. flavovestitus vs S. habenus

      S. habenus - Leg, tibia and tarsal segments are dark brown-black - Metepisturnum, border with lateral face of propodeum, lined with bright gold, short, prone appressed hairs that are easy to see - Abdomen always dark - Dorsal portion of the propodeum completely cloaked in golden reflective hairs, the integument not visible - S8 in MALES UNIQUE with a huge bowl-like depression

      S dorsalis - Leg, tibia and tarsal segments are orange-red only in the female males are usually all dark - Metepisturnum, border with lateral face of propodeum, lined with bright silver/gold, short, prone appressed hairs that are easy to see - Female abdomen always with some red on the basal tergites - Males usually, but not always a black abdomen - In direct comparison, smaller than the other two species - Dorsal portion of the propodeum OF THE FEMALE cloaked in silver reflective hairs, these can vary from dense enough to hide the integument or sparser THE MALE has golden hairs but the integument is visible between the hairs - S8 in MALES UNIQUE, the entire segment an acute triangle and coming to a clear sharp point

      S. flavovestitus - Leg, tibia and tarsal segments are orange-red - Metepisturnum, border with lateral face of propodeum, WITHOUT with obvious bright silver/gold, short, prone appressed hairs, there are long hair present, and sometimes a faint hint of appressed reflective hairs, but these are not obvious at first glance - Dorsal portion of the propodeum integument clearly visible with only a light coating of hairs - S8 in MALES UNIQUE in that there is s small, medial acute point along the rim, but this point set within the broader edge of the rim which is slightly concave

      Lasioglossum lustrans

      John Ascher found a L. (Hemihalictus) lustrans male from WI with 3 submarginal cells in both wings. This species is one of the few in Lasioglossum that normally has but 2 submarginal cells.


      Perdita ignota

      Mike Arduser noted that P. ignota occurs in Illinois in Madison Co. on a sand prairie remnant and notes:

      "P. ignota is an unusual species- occurs in “hard soil” habitats as well as in sandy sites – I don’t know of any other Perdita east of the Rockies with that kind of habitat latitude.  I’m considering Timberlakes’s P. nubila (type from/near Branson MO) to be a synonym of P. ignota."

      P. nubila has been a tough species to deal with due to the variation in coloration...another candidate for further study.

      Mystery Map - A Tale of 2 Species

      Washington D.C.   -  Species 1

       

      Carolina Sandhills National Wildlife Refuge - SC

      Other species of the genus from Carolina Sandhills National Wildlife Refuge

      Answers:  In Washington D.C.  that would be Perdita octomaculata....located only along the sandy side of the Patuxent River where over the millennia large amounts of sand accumulated from the prevailing winds.   In the sandhills its P. consobrina the kissing cousing of P. octomaculata varying largely  by the distribution of yellow on its body.                                              

      Sam Droege  sdroege@...                      
      w 301-497-5840 h 301-390-7759 fax 301-497-5624
      USGS Patuxent Wildlife Research Center
      BARC-EAST, BLDG 308, RM 124 10300 Balt. Ave., Beltsville, MD  20705
      Http://www.pwrc.usgs.gov



      The Cage

      Wheatgrass it is called
      in the catalog, but here it is July
      when the sun has burned the color
      of spring from my nose and only dust
      and dried weeds can remember. All
      is known beneath blue sky
      but swimming in a midnight pool
      is grace that cruelly glides
      away from me. Tomorrow I will build
      a house of clouds, protection
      from the dance of stars,
      impale this lifetime on my thumb to stroke
      and hold so when the plum explodes
      I can escape
      before my throat is soaked
      in sweet and salt.


      - Dani Bundy

      P Bees are not optional.