This is similar in many respects to Nomada texana, but it has more red on on the propodeum, red on the underside of the head and slightly different yellow markings on the sternum.  For convenience,  in the yellow box below, I posted photographs of a male Nomada texana  from Mission, which  you identified for us two years ago.

Nomada vierecki

Size:  8.5 mm (male) 

When seen: May  29, 2021
Falcon State Park
Starr County

Male bee - from Falcon Park, Starr County
Male bee - from Falcon Park, Starr County
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Lateral view of bee

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Dorsal view of thorx

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Profile of face and thorax

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male bee

FOR COMPARISON:  Below is a Nomada texana  from
Mission  that you identified for us two years ago.

A male Texas nomad bee

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Dorsal view of male bee: the Texas nomad bee has a mostly black propodeum.

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When I first saw the resin bee below, I thought i must be Megachile exilis,  but it has more extensive red coloration than the M. exilis that are common in Mission.  (I've posted below the pictures of this bee, photos of a Megachile exilis from the National Butterfly Center that you identified for us two years ago.)

Megachile prosopodis  - resin bee

Size:  mm (male) 

Associated plant:

Shrubby blue salvia

(Salvia ballotiflora)

Family: Laminaceae 

When seen: June 3, 2021
Falcon State Park
Starr County

Male bee - from Falcon Park, Starr County
Male bee - from Falcon Park, Starr County
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Face

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Profile of head

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Dorsal view of bee: the upper legs of the bee are black

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On all legs, the tibiae, basitarsi and tarsi are partly red. The expanded part of the front leg is smaller and less elaborate than on Megachile exilis.

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male bee

Below is the Megahile exilis male from Mission  that you identified for us two years ago.

A male slender resin bee: male slender resin bees have distinctive red forelegs with expanded lower segments.

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A closer view of a male bee's foreleg

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male slender resin bees have 3 teeth in each jaw. Their faces are covered with dense white hairs.

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A male slender resin bee standing on its head by gripping a snout bean vine with its jaws

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Protandrena bancrofti 
Size:  11.5 mm (female) 

Associated plant:
Unidentified orange  mallow 

Plant family: Malvaceea

When seen: June 2, 2021
Mesteno Ranch, Puerto Rico TX
NW Hidalgo County

Female bee - from Mesteno Ranch, NW Hidalgo County
Female bee - from Mesteno Ranch, NW Hidalgo County
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Female bee

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Face - ivory mask

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Alternate view

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Dorsal view of thorax & vertex

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Female Protandrena

female bee - NW Hidalgo County

female bee

Colletes mandibularis female

Size:  9 mm (female) 

Associated plant:

Coastal lazydaisy

Aphanostephus skirrhobasis [

Family:   Asteraceae

When seen: June 2, 2021
El Mesteno Ranch

Puerto Rico, TX
NW Hidalgo County

Female bee - from Mesteno Ranch NW Hidalgo County
Female bee - from Mesteno Ranch NW Hidalgo County
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This is a small Colletes (shown here on dime).

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Face of female

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Profile of face, cheek, malar space

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female bee