SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cfaeba7740ff4dc9b3d05301103def1096c4a82185f805d93441b69990b98dfe' 
  AND token = 'Nuor2DKSYjTdjHe+HLABbF9tmosGIMJcR7VeSJM+02Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}