Anthidium schwarzi

Taxonomy

Family: Megachilidae
Subfamily: Megachilinae
Tribe: Anthidiini
Genus: Anthidium Fabricius, 1804
Subgenus: A. (Anthidium) Fabricius, 1804
Species: Anthidium schwarzi Gonzalez and Griswold, 2013
Common name: none

Overview

Anthidium (Anthidium) schwarzi are dark brown to black with yellow maculations (Gonzalez and Griswold 2013Gonzalez and Griswold 2013:
Gonzalez, V.H. and T.L. Griswold. 2013. Wool carder bees of the genus Anthidium in the Western Hemisphere (Hymenoptera: Megachilidae): diversity, host plant associations, phylogeny, and biogeography. Zoological Journal 168: 221ndash;425.). Females have white to yellowish pubescencepubescence:
short, fine hair
, except for the brown hairs found on the middle tibiatibia:
the segment of the leg, between the femur and the tarsus
, inner tarsitarsi:
the group of segments at the end of the leg following the tibia
, and S1S1:
the plates on the underside of the abdomen, often abbreviated when referring to a specific segment to S1, S2, S3, S4, S5, S6, S7, or S8
. Females range in body length from 9.1–11.5 mm (Gonzalez and Griswold 2013Gonzalez and Griswold 2013:
Gonzalez, V.H. and T.L. Griswold. 2013. Wool carder bees of the genus Anthidium in the Western Hemisphere (Hymenoptera: Megachilidae): diversity, host plant associations, phylogeny, and biogeography. Zoological Journal 168: 221ndash;425.). Male pubescencepubescence:
short, fine hair
is lighter than that of females. Males range in body length from 11.5–14.3 mm (Gonzalez and Griswold 2013Gonzalez and Griswold 2013:
Gonzalez, V.H. and T.L. Griswold. 2013. Wool carder bees of the genus Anthidium in the Western Hemisphere (Hymenoptera: Megachilidae): diversity, host plant associations, phylogeny, and biogeography. Zoological Journal 168: 221ndash;425.).

Diagnostic characteristics

(modified from Gonzalez and Griswold 2013Gonzalez and Griswold 2013:
Gonzalez, V.H. and T.L. Griswold. 2013. Wool carder bees of the genus Anthidium in the Western Hemisphere (Hymenoptera: Megachilidae): diversity, host plant associations, phylogeny, and biogeography. Zoological Journal 168: 221ndash;425.)

• Female labrumlabrum:
  part of the head abutting the clypeus, folds down in front of the mouthparts
  has two large preapicalpreapical:
  referring to a section of a bee that is physically found just before the outermost (or apical) end of the section or segment
  projections that point upwards but lack basalbasal:
  originating at the foundation of a structure
  protuberances.
• Female mandiblemandible:
  bee teeth, so to speak, usually crossed and folded in front of the mouth
  has 5–6 teeth.
• Female propodealpropodeal:
  the last segment of the thorax
  triangle is weakly lineolatelineolate:
  marked with fine lines
  and shiny.
• Female hind tibiatibia:
  the segment of the leg, between the femur and the tarsus
  without anterioranterior:
  toward the head or on the head side of a segment being described
  carina.
• Female T1–T5 discal areas are slightly elevated, dull, and weakly imbricateimbricate:
  overlapping, like shingles or roof tiles
  between punctures.
• Female T6T6:
  the segments on the top side of the abdomen, often abbreviated when referring to a specific segment to T1, T2, T3, T4, T5, T6, or T7
  lacks a preapicalpreapical:
  referring to a section of a bee that is physically found just before the outermost (or apical) end of the section or segment
  carinacarina:
  a clearly defined ridge or keel, not necessarily high or acute; usually appears on bees as simply a raised line
  .
• Female T6T6:
  the segments on the top side of the abdomen, often abbreviated when referring to a specific segment to T1, T2, T3, T4, T5, T6, or T7
  has a strong laterallateral:
  relating, pertaining, or attached to the side
  spine, a small median emarginationemargination:
  a notched or cut out place in an edge or margin, can be dramatic or simply a subtle inward departure from the general curve or line of the margin or structure being described
  , and a depressed apicalapical:
  near or at the apex or end of any structure
  rim that projects laterally into a submedian lobe.
• Male labrumlabrum:
  part of the head abutting the clypeus, folds down in front of the mouthparts
  preapical projections are larger than in females.
• Male S4S4:
  the plates on the underside of the abdomen, often abbreviated when referring to a specific segment to S1, S2, S3, S4, S5, S6, S7, or S8
  with median apicalapical:
  near or at the apex or end of any structure
  brush of long, dense, black apicalapical:
  near or at the apex or end of any structure
  hairs.
• Male S4S4:
  the plates on the underside of the abdomen, often abbreviated when referring to a specific segment to S1, S2, S3, S4, S5, S6, S7, or S8
  apicalapical:
  near or at the apex or end of any structure
  margin is concave medially.
• Male S6S6:
  the plates on the underside of the abdomen, often abbreviated when referring to a specific segment to S1, S2, S3, S4, S5, S6, S7, or S8
  laterallateral:
  relating, pertaining, or attached to the side
  lobes are short and broad, and median lobe is sub-rectangular and notched medially.
• Male S7S7:
  the plates on the underside of the abdomen, often abbreviated when referring to a specific segment to S1, S2, S3, S4, S5, S6, S7, or S8
  distaldistal:
  place on a segment that is furthest from the place of attachment with the body
  margin is concave.
• Male S8S8:
  the plates on the underside of the abdomen, often abbreviated when referring to a specific segment to S1, S2, S3, S4, S5, S6, S7, or S8
  apicalapical:
  near or at the apex or end of any structure
  process is diamond-shaped, and strongly curved ventrally in profile.
• Male T6T6:
  the segments on the top side of the abdomen, often abbreviated when referring to a specific segment to T1, T2, T3, T4, T5, T6, or T7
  laterallateral:
  relating, pertaining, or attached to the side
  spine is straight and as long as T7T7:
  the segments on the top side of the abdomen, often abbreviated when referring to a specific segment to T1, T2, T3, T4, T5, T6, or T7
  median spine.
• Male T7T7:
  the segments on the top side of the abdomen, often abbreviated when referring to a specific segment to T1, T2, T3, T4, T5, T6, or T7
  laterallateral:
  relating, pertaining, or attached to the side
  lobe is elongate and rounded apicallyapically:
  near or at the apex or end of any structure
  .

May be confused with

Female A. schwarzi may be confused with A. palmarumdue to the combination of basitarsibasitarsi:
the segment of the tarsus that is the nearest to the body of the bee, usually the largest of all the tarsal segments
covered with dense tomentumtomentum:
a form of pubescence composed of short matted, woolly hair
and T6T6:
the segments on the top side of the abdomen, often abbreviated when referring to a specific segment to T1, T2, T3, T4, T5, T6, or T7
with distinct sublateral lobes (Gonzalez and Griswold 2013Gonzalez and Griswold 2013:
Gonzalez, V.H. and T.L. Griswold. 2013. Wool carder bees of the genus Anthidium in the Western Hemisphere (Hymenoptera: Megachilidae): diversity, host plant associations, phylogeny, and biogeography. Zoological Journal 168: 221ndash;425.). Female A. schwarzi can be differentiated from A. palmarumby the presence of distinct laterallateral:
relating, pertaining, or attached to the side
spines on T6T6:
the segments on the top side of the abdomen, often abbreviated when referring to a specific segment to T1, T2, T3, T4, T5, T6, or T7
and the reduced or absent yellow markings on the face and mandibles (Gonzalez and Griswold 2013Gonzalez and Griswold 2013:
Gonzalez, V.H. and T.L. Griswold. 2013. Wool carder bees of the genus Anthidium in the Western Hemisphere (Hymenoptera: Megachilidae): diversity, host plant associations, phylogeny, and biogeography. Zoological Journal 168: 221ndash;425.). Male A. schwarzi can be differentiated from A. palmarumby the rounded laterallateral:
relating, pertaining, or attached to the side
lobes of T7T7:
the segments on the top side of the abdomen, often abbreviated when referring to a specific segment to T1, T2, T3, T4, T5, T6, or T7
, S7S7:
the plates on the underside of the abdomen, often abbreviated when referring to a specific segment to S1, S2, S3, S4, S5, S6, S7, or S8
with a concave apicalapical:
near or at the apex or end of any structure
margin, and a more curved apicalapical:
near or at the apex or end of any structure
process on S8S8:
the plates on the underside of the abdomen, often abbreviated when referring to a specific segment to S1, S2, S3, S4, S5, S6, S7, or S8
. Male A. schwarzi may be also confused with A. collectum due to the shape of T7T7:
the segments on the top side of the abdomen, often abbreviated when referring to a specific segment to T1, T2, T3, T4, T5, T6, or T7
with narrowly rounded laterallateral:
relating, pertaining, or attached to the side
lobes; S4S4:
the plates on the underside of the abdomen, often abbreviated when referring to a specific segment to S1, S2, S3, S4, S5, S6, S7, or S8
with a concave apicalapical:
near or at the apex or end of any structure
margin and a median apicalapical:
near or at the apex or end of any structure
brush of dense black hairs; and S6S6:
the plates on the underside of the abdomen, often abbreviated when referring to a specific segment to S1, S2, S3, S4, S5, S6, S7, or S8
with a median, small, apicallyapically:
near or at the apex or end of any structure
notched lobe (Gonzalez and Griswold 2013Gonzalez and Griswold 2013:
Gonzalez, V.H. and T.L. Griswold. 2013. Wool carder bees of the genus Anthidium in the Western Hemisphere (Hymenoptera: Megachilidae): diversity, host plant associations, phylogeny, and biogeography. Zoological Journal 168: 221ndash;425.). Male A. schwarzi can be differentiated from male A. collectumby broader laterallateral:
relating, pertaining, or attached to the side
lobes on T7T7:
the segments on the top side of the abdomen, often abbreviated when referring to a specific segment to T1, T2, T3, T4, T5, T6, or T7
and a more concave distaldistal:
place on a segment that is furthest from the place of attachment with the body
margin of S4S4:
the plates on the underside of the abdomen, often abbreviated when referring to a specific segment to S1, S2, S3, S4, S5, S6, S7, or S8
with longer hairs on the S4S4:
the plates on the underside of the abdomen, often abbreviated when referring to a specific segment to S1, S2, S3, S4, S5, S6, S7, or S8
median apicalapical:
near or at the apex or end of any structure
brush (Gonzalez and Griswold 2013Gonzalez and Griswold 2013:
Gonzalez, V.H. and T.L. Griswold. 2013. Wool carder bees of the genus Anthidium in the Western Hemisphere (Hymenoptera: Megachilidae): diversity, host plant associations, phylogeny, and biogeography. Zoological Journal 168: 221ndash;425.).

Phenology

Anthidium schwarzi adults have been recorded in flight from April to early July, with peak activity occurring from April to May (Gonzalez and Griswold 2013Gonzalez and Griswold 2013:
Gonzalez, V.H. and T.L. Griswold. 2013. Wool carder bees of the genus Anthidium in the Western Hemisphere (Hymenoptera: Megachilidae): diversity, host plant associations, phylogeny, and biogeography. Zoological Journal 168: 221ndash;425.).

Host associations

Anthidium schwarzi is a generalist that has been observed visiting a variety of species within Asteraceae, Boraginaceae, Fabaceae, and Malvaceae (Gonzalez and Griswold 2013Gonzalez and Griswold 2013:
Gonzalez, V.H. and T.L. Griswold. 2013. Wool carder bees of the genus Anthidium in the Western Hemisphere (Hymenoptera: Megachilidae): diversity, host plant associations, phylogeny, and biogeography. Zoological Journal 168: 221ndash;425.). However, A. schwarzi has such a strong preference for Phacelia (Boraginaceae) that it may be a specialist (Gonzalez and Griswold 2013Gonzalez and Griswold 2013:
Gonzalez, V.H. and T.L. Griswold. 2013. Wool carder bees of the genus Anthidium in the Western Hemisphere (Hymenoptera: Megachilidae): diversity, host plant associations, phylogeny, and biogeography. Zoological Journal 168: 221ndash;425.).

Nesting behavior

Nesting behavior is unknown.

Distribution

Anthidium schwarzi occur in the U.S. throughout northern Arizona, southern Nevada, New Mexico, western Texas, and Utah. In Mexico, they can be found in Sonora. They are found in the Chihuahuan Desert, Colorado Plateau shrublands, Western short grasslands, and occasionally in the Great Basin and eastern Mojave Desert (Gonzalez and Griswold 2013Gonzalez and Griswold 2013:
Gonzalez, V.H. and T.L. Griswold. 2013. Wool carder bees of the genus Anthidium in the Western Hemisphere (Hymenoptera: Megachilidae): diversity, host plant associations, phylogeny, and biogeography. Zoological Journal 168: 221ndash;425.).

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References

Gonzalez, V.H. and T.L. Griswold. 2013. Wool carder bees of the genus Anthidium in the Western Hemisphere (Hymenoptera: Megachilidae): diversity, host plant associations, phylogeny, and biogeography. Zoological Journal of the Linnean Society 168: 221-425.