Anthidium mormonum

Taxonomy

Family: Megachilidae
Subfamily: Megachilinae
Tribe: Anthidiini
Genus: Anthidium Fabricius, 1804
Subgenus: A. (Anthidium) Fabricius, 1804
Species: Anthidium mormonum Cresson, 1878
Common name: none

Overview

Anthidium (Anthidium) mormonum are black with light reddish-brown coloration on the tarsitarsi:
the group of segments at the end of the leg following the tibia
and 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 light ferruginousferruginous:
rust-colored
pubescence, sometimes with slightly darker coloration on the face, vertexvertex:
the area between the ocelli and the back of the head
, scutumscutum:
the large segment on top of the thorax located between the wings and behind the head
, axillaaxilla:
the triangular or rounded point on the thorax where thoracic muscles meet the forewing of an insect
, scutellumscutellum:
shield shaped plate behind scutum
, inner tarsitarsi:
the group of segments at the end of the leg following the tibia
, and sides of propodeumpropodeum:
the last segment of the thorax
. The clypeusclypeus:
a section of the face below the antennae, demarcated by the epistomal sutures
and supraclypeal areasupraclypeal area:
the region of the head between the antennal sockets and clypeus, demarcated on the sides by the subantennal sutures
is covered with erect, simple, apicallyapically:
near or at the apex or end of any structure
curved hairs. Females have a body length of 8.0–11.2 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.). Males have dense, brown, short, stout, simple hairs on the ventralventral:
of, on, or relating to the underside of an animal, or segment of an animal
surface of the hind coxacoxa:
the basal segment of the leg
. Males range in body length from 7.7–13.0 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
  is elevated basally and 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 curve upwards.
• 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 dull and finely lineolatelineolate:
  marked with fine lines
  to imbricateimbricate:
  overlapping, like shingles or roof tiles
  .
• 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 strongly elevated and weakly shiny between dense punctures.
• Female T1–T5 depressed marginal zones have nearly contiguous punctures.
• Female T1–T5 impunctateimpunctate:
  marked with punctures or pits
  apicalapical:
  near or at the apex or end of any structure
  zones are dull and narrow with doubly carinatecarinate:
  having keels or carinae
  margins.
• 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
  apicalapical:
  near or at the apex or end of any structure
  rim is distinctly depressed and medially projected.
• 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
  median apicalapical:
  near or at the apex or end of any structure
  brush is narrow, with light reddish-brown hairs that can be difficult to see among sternal hairs. The apicalapical:
  near or at the apex or end of any structure
  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
  is straight 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
  with pointed laterallateral:
  relating, pertaining, or attached to the side
  lobes and a broadly rounded median lobe.
• 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
  is truncatetruncate:
  ending abruptly, or squared off
  apicallyapically:
  near or at the apex or end of any structure
  .
• 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 long, narrow, and deeply bifidbifid:
  divided into two branches; forked
  apicallyapically:
  near or at the apex or end of any structure
  with ventrally bent pointed lobes.
• 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 the 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 apicallyapically:
  near or at the apex or end of any structure
  rounded, and 1.0–1.5 times wider than the distance between the inner margin and median spine.

May be confused with

Female A. mormonum can be easily distinguished from all other Anthidium species in the U.S. by the combination of a distinctly dull propodeumpropodeum:
the last segment of the thorax
, lack of the anterioranterior:
toward the head or on the head side of a segment being described
carina on the hind tibiatibia:
the segment of the leg, between the femur and the tarsus
, lack of dense tomentumtomentum:
a form of pubescence composed of short matted, woolly hair
on the outer basitarsibasitarsi:
the segment of the tarsus that is the nearest to the body of the bee, usually the largest of all the tarsal segments
, and depressed apicalapical:
near or at the apex or end of any structure
rim of 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
that is distinctly projected medially. Male A. mormonum can be distinguished from other Anthidium by the combination of apicallyapically:
near or at the apex or end of any structure
rounded laterallateral:
relating, pertaining, or attached to the side
lobe 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
, acute laterallateral:
relating, pertaining, or attached to the side
lobes and broadly rounded median lobe of 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
, and reddish-brown, sparse, and indistinct median apicalapical:
near or at the apex or end of any structure
brush of hairs on 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
(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.).

Small specimens of A. mormonum may be confused with A. utahense; however, A. mormonum can be differentiated by the dull propodealpropodeal:
the last segment of the thorax
triangle, the shape of 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
in females, and 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 a rounded laterallateral:
relating, pertaining, or attached to the side
lobe in males (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 mormonum adults have been recorded in flight from March to early September, with peak activity occurring from May to August (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 mormonum is a generalist that has been observed visiting a variety of species within Apiaceae, Asteraceae, Boraginaceae, Brassicaceae, Cactaceae, Caryophyllaceae, Crassulaceae, Fabaceae, Geraniaceae, Iridaceae, Lamiaceae, Malvaceae, Onagraceae, Phrymaceae, Plantaginaceae, Polemoniaceae, Polygonaceae, Portulacaceae, Rhamnaceae, and Rosaceae (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

Anthidium mormonum nest in preexisting cavities in abandoned beetle tunnels in old yucca flower stalks (Agavaceae) and oak stumps (Fagaceae). Each nest has between one and four cells. Nests are comprised of trichomes from Lepidospartum squamatum (Asteraceae). Females have been observed competing over nest space. During this altercation, the females grabbed each other, and attempted to bite and sting each other as they fell to the ground (Hicks 1929Hicks 1929:
Hicks, C.H. 1929. On the nesting habits of Callanthidium illustre (Cresson). The Canadian Entomologist 61: 1ndash;8.).

Distribution

In the U.S., Anthidium mormonum occur from the Pacific coast to Montana, western South Dakota, western Nebraska, Colorado, and New Mexico. In Canada, they are found in British Columbia. In Mexico, they occur in northern Baja California. They are restricted to forests, Mediterranean California chaparral and woodlands, shrublands, and shrub steppes (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.

Hicks, C.H. 1929. The nesting habits of Anthidium mormonum fragariellum Cockerell (Hymenoptera: Megachilidae). Entomological News 40: 105-110.