Brachycybe

Brachycybe (Greek for "short head") is a genus of andrognathid millipedes with species in the United States and East Asia. In a rare example of paternal care in invertebrates, males of most species guard the eggs until they hatch.

Brachycybe
Brachycybe lecontii
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Diplopoda
Order: Platydesmida
Family: Andrognathidae
Genus: Brachycybe
Wood, 1864
Type species
Brachycybe lecontii
Wood, 1864
Species
  • B. californica (Karsch, 1880)
  • B. cooki Loomis, 1942
  • B. disticha Mikhaljova, 2010
  • B. lecontii Wood, 1864
  • B. nodulosa Loomis, 1936
  • B. petasata Loomis, 1936
  • B. picta Gardner, 1975
  • B. potterinus Chamberli, 1941
  • B. producta Loomis, 1936
  • B. rosea Murray, 1877
Synonyms

Sinocybe Loomis, 1942

Description

Brachycybe species are rather similar in appearance, varying in subtle features of the collum (first body segment) and paranota (lateral “keels” extending off of body segments). Individuals attain lengths up to 1 inch (25 mm) and range in color from orange to tan to pink. B. picta is uniquely patterned with 5 brown spots.[1] The 9th and 10th pair of legs in mature males are modified into gonopods (reproductive appendages), and although gonopods are widely used to determine species in millipedes, the relatively simple gonopods of Brachycbe and other members of the Platydesmida show little variation and are not readily useful for species identification.[2]

Ecology

While most millipedes feed on leaf litter or other plant matter, Brachycybe are thought to feed primarily on fungus, and may be found under rotting logs or stumps.

Adult Brachycybe lecontii with hatchlings.
Hatchling Bracycybe lecontii feeding on fungi.

Egg brooding

Male egg brooding (care of eggs) has been extensively studied in B. nodulosa, a species found in Japan and South Korea. After the female lays eggs, the male coils his body around the mass, and guards them until hatching, a behavior thought to protect the eggs from soil-dwelling fungi or predators such as ants.[3]

Species
Dorsal views of North American Brachycybe head and anterior segments. Upper row: B. petasata and B. lecontii. Lower row: B. rosea and B. producta, also showing mid body segments.

At least ten species have been named, and at least two undescribed species have been identified by genetic analysis. Studies of genetic differences suggest the genus originated in California around 50 million years ago.[2]

  • B. californica (Karsch, 1880) i c g
  • B. cooki Loomis, 1942 - Jiangxi Province, China
  • B. disticha Mikhaljova, Golovatch, Korsós, Chen & Chang, 2010 g - Taiwan
  • B. lecontii Wood, 1864 i c g b - Southeastern United States, from Virginia to Illinois and Kansas, south to Louisiana and southern Alabama.
  • B. nodulosa Verhoeff, 1935 - Central and Southern Japan, southern South Korea.
  • B. petasata Loomis, 1936 i c g b - Southern Appalachians: in adjacent parts of North Carolina, Georgia, Alabama, and Tennessee.
  • B. picta Gardner, 1975 i c g - Northern California: Marin County and Mendocino County.
  • B. potterinus Chamberli, 1941 c g
  • B. producta Loomis, 1936 i c g b - Northern California
  • B. rosea Murray, 1877 i c g b - Northern California

Data sources: i = ITIS,[4] c = Catalogue of Life,[5] g = GBIF,[6] b = Bugguide.net[7]

References
  1. Enghoff, Henrik (2011). "Trans-segmental serial colour patterns in millipedes and their developmental interpretation (Diplopoda)". International Journal of Myriapodology. 6: 1–27. doi:10.3897/ijm.6.1949.
  2. Brewer, Michael S.; Spruill, Chad L.; Rao, Nandita S.; Bond, Jason E. (2012). "Phylogenetics of the millipede genus Brachycybe Wood, 1864 (Diplopoda: Platydesmida: Andrognathidae): Patterns of deep evolutionary history and recent speciation". Molecular Phylogenetics and Evolution. 64 (1): 232–242. doi:10.1016/j.ympev.2012.04.003. PMID 22516430.
  3. Kudo, Shin-Ichi; Akagi, Yoshinobu; Hiraoka, Shuichiro; Tanabe, Tsutomu; Morimoto, Gen (2011). "Exclusive Male Egg Care and Determinants of Brooding Success in a Millipede". Ethology. 117 (1): 19–27. doi:10.1111/j.1439-0310.2010.01851.x.
  4. "Pythidae Report". Integrated Taxonomic Information System. Retrieved 2018-05-06.
  5. "Browse Pythidae". Catalogue of Life. Retrieved 2018-05-06.
  6. "Pythidae". GBIF. Retrieved 2018-05-06.
  7. "Pythidae Family Information". BugGuide.net. Retrieved 2018-05-06.
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.