PetriKey

Fungus

Coccidioides immitis/posadasii

Dimorphic fungus with spherules

kok-sid-ee-OY-deez

fungusdimorphicspherulesouthwestsoil

High-yield clue

Spherules with endospores + Southwest desert exposure vocabulary.

Overview

A dimorphic fungus group used to teach spherules with endospores, desert Southwest geography vocabulary, and pulmonary nodule comparison.

Classification

  • Fungus
  • Dimorphic fungus
  • Spherule tissue form

Lab & identification clues

  • Spherule/endospore morphology
  • Serology vocabulary
  • Culture hazard awareness without procedure details

Associations

  • Valley fever vocabulary
  • Pulmonary nodule/cavity terms
  • Dissemination risk framing

Commonly confused with

  • Histoplasma capsulatum
  • Blastomyces dermatitidis

Your notes

Original student-study summary. Sources checked: OpenStax Microbiology 2e, NCBI Bookshelf Medical Microbiology, and CDC topic pages where applicable; reviewed 2026-06. Educational only; no diagnosis, treatment, dosing, or specimen-handling guidance.

OpenStax: Microbiology 2e organism classification foundationssourceNCBI Bookshelf: Medical Microbiology organism chapterssourceCDC: CDC disease and public-health topic pagessource