Sennertia alfkeni (Oudemans, 1900)

Fig. 1. Sennertia alfkeni, heteromorphic deutonymph, China, ex Xylocopa appendiculata (BMOC 90-1212-001). Click here to enlarge

Bee Mites : Acari : Acariformes : Sarcoptiformes : Chaetodactylidae : Sennertia

Sennertia alfkeni (Oudemans, 1900)

Trichotarsus alfkeni Oudemans, 1900: 115, Fig. 18-20 (lectotype and 3 paralectotype HDNs in RMNH, designated by Fain, 1974b); Oudemans, 1901: 82 (included in key); Oudemans, 1903a: 147 (included in key, assigned to group D in Trichotarsus);

Trichotarsus Alfkeni: Vitzthum, 1912c: 233 (part., only specimens from X. circumvolans); Vitzthum, 1912d: 290 (comparison with S. horrida)

Trichotarsus japonicus Oudemans, 1900: 117, Fig. 21 (holotype HDN (Japan: Kōbe, ex Xylocopa circumvolans) in RMNH (Fain, 1974b)), synonymized by Zachvatkin (1941), confirmed by Okabe et al., 2008 and Kawazoe at al., 2008; Oudemans, 1901: 83 (included in key); Oudemans, 1903a: 147 (included in key, assigned to group D in Trichotarsus); Trägårdh, 1904: 156 (comparison with S. simplex)

Sennertia alfkeni: Oudemans, 1905a: 22; Sennertia alfkeni: Vitzthum, 1919: 31 (comparison of HDN with S. morstatti, S. horrida); Oudemans, 1924: 329 (comparison with S. sumatrensis); Vitzthum, 1941: 308 (comparison with Sennertia frontalis; species year description given as 1899); Zachvatkin, 1941: 389, Figs 672-644 (Japan, Korea, China, ex Xylocopa circumvolans (as "X. kalinovskii Rad." =Xylocopa kalinowskii Radoszkowski; redescription of HDN, included in key, Sennertia japonica considered as junior synonym of S. alfkeni; species description year given as 1901); Fain, 1974b: 229, Figs. 11-12, 15-16 (redescription of lectotype; species description year given as 1901); Delfinado & Baker, 1976: 85 (comparison with S. americana); Okabe & Makino, 2002: 73, Fig: 5, 6 (SEM pictures, preferred attachment site on host: dorsolateral hairs); Klimov and OConnor, 2008: 222; Okabe et al., 2008: 1361 (description of feeding stages, confirming synonymy with Sennertia japonica based on rearing experiments)

Sennertia japonica: Oudemans, 1905a: 22 (as Tr. japonicus); Vitzthum, 1914: 323 (comparison with HDN of S. morstatti); Vitzthum, 1919: 43 (comparison with S. morstatti and S. horrida, species year description indicated as 1899); Vitzthum, 1941: 308 (comparison with S. frontalis; species year description given as 1899); Okabe & Makino, 2002: 73, Fig: 2a, 3 (color photos in acarinaria), Fig. 4 (ESEM picture; preferred attachment sites: mesosomal and metasomal acarinaria)

Sennertia japonicus: Fain, 1974b: 224, Figs. 5-6 ("species description year given as 1901")

Sennertia ?bifilis: Womersley, 1941: 480, Fig. 17 (Australia: Queensland, ex Xylocopa (Koptortosoma) bryorum (as "Mesotricha bryorum")) (after Fain, 1982)

Sennertia (Sennertia) alfkeni: Fain, 1981a: 163 (redescription of HDN, included in key, subgeneric assignment, assigned to japonica-group, stated that type in RMNH, species description year given as 1901); Fain, 1982: 70 (species description year given as 1901); OConnor, 1993a: 362 (genus-level character acquisition; species description year given as 1901); Kawazoe at al., 2008: 504 (COI sequence data indicate 4 groups corresponding to 4 allopatric hosts, except for mite populations from the northern range of Xylocopa amamensis, which are similar to mites from X. circumvolans)

Sennertia (Sennertia) japonicus: Fain, 1981a: 163 (included in key, subgeneric assignment, assigned to japonica-group; year of species description indicated as 1901)

Misidentifications:

Trichotarsus Alfkeni: Vitzthum, 1912c: 233, Figs 19-20 (ex Xylocopa (Koptortosoma) aestuans (as Koptorthosoma aestuans) (East Sumatra), Xylocopa (Koptortosoma) caerulea (as Koptorthosoma coerulea) (Java))

Material (show database records).
Biology. This species was known as two separate species Sennertia alfkeni and S. japonica, but it was later shown that these two are genetically the same (Kawazoe et al., 2008) and morphological differences between them are probably continuous and size-dependant (Zachvatkin, 1941; Okabe and Makino, 2008).
Phoretic deutonymphs of the alfkeni-type attach themselves to the dorsoalateral hairs, while those of the japonica-type were common in the mesosomal and metasomal acarinaria of the host. The deutonymphs of both groups display allometric differences. The alfkeni-type deutonymphs are larger (311.8±36.9 μm), with the claw measuring 50.5±8.2 μm, and the ambulacra with a projection, whereas japonica-type deutonymphs are smaller (232.0±18.5 μm), with the claw size 14.7±2.2 μm, and lacking ambulacral projection (Okabe and Makino, 2002; Okabe et al., 2008; Kawazoe et al., 2008). The ambulacral projection found in alfkeni-type deutonymphs apparently aids in the attachment to the host’s hair. In contrast, deutonymphs of the japonica-type do not attach to hairs and are phoretic inside acarinaria, specialized internal structures on the host body serving for mite transfer.
Adults also expressed variation in the form of the dorsal setae, ranging from narrow to broad (Okabe et al., 2008).

Hosts.
Xylocopa (Alloxylocopa) appendiculata Smith, 1852 (=Xylocopa appendiculata circumvolans) (type host).
Xylocopa (Alloxylocopa) amamensis Sonan, 1934
Xylocopa (Alloxylocopa) flavifrons Matsumura, 1912
Xylocopa (Alloxylocopa) albinotum Matsumura, 1926

Distribution (show map). Japan, including Kōbe (type locality), mainland China; "Korea"; Australia (Fain, 1974b; Fain, 1982; Zachvatkin, 1941; Okabe & Makino, 2002; Kawazoe at al., 2008).

References

Delfinado, M. D. & E. W. Baker. 1976. Notes on hypopi (Acarina) associated with bees and wasps (Hymenoptera). Journal of the New York Entomological Society.84: 76-90.

Fain, A. 1974. The hypopi of the genus Sennertia Oudemans, 1905 described by Oudemans (Acarina, Sarcoptiformes). Zoologische Meded. Leiden.48: 119-231.

Fain, A. 1981. A revision of the phoretic deutonymphs (hypopi) of the genus Sennertia Oudemans, 1905 (Acari, Astigmata, Chaetodactylidae). Systematic Parasitology.3: 145-183.

Fain, A. 1982. Sennertia Oudemans (Acari, Chaetodactylidae) on Australian bees. Transactions of the Royal Society of South Australia.106: 67-70.

Kawazoe, K., A. Kawakita, Y. Kameda & M. Kato. 2008. Redundant species, cryptic host-associated divergence, and secondary shift in Sennertia mites (Acari: Chaetodactylidae) associated with four large carpenter bees (Hymenoptera: Apidae: Xylocopa) in the Japanese island arc. Molecular Phylogenetics and Evolution.49: 503-513.

Kawazoe, K., K. Okabe, A. Kawakita & M. Kato. 2010. An alien Sennertia mite (Acari: Chaetodactylidae) associated with an introduced Oriental bamboo-nesting large carpenter bee (Hymenoptera: Apidae: Xylocopa) invading the central Honshu Island, Japan. Entomological Science.13: 303-310.

Klimov, P. B. & B. M. OConnor. 2008. Morphology, evolution, and host associations of bee-associated mites of the family Chaetodactylidae (Acari: Astigmata), with a monographic revision of North American taxa. Miscellaneous Publications Museum of Zoology University of Michigan.199: 1-243.

OConnor, B. M. 1993. Generic relationships in the Chaetodactylidae (Acari: Astigmata) with description of a new genus. Acarologia.34: 345-362.

Okabe, K. & S. Makino. 2002. Phoretic mite fauna on the large carpenter bee Xylocopa appendiculata circumvolans (Hymenoptera: Apidae) with descriptions of its acarinaria on both sexes. Journal of Acarological Society of Japan.11: 73-84.

Okabe, K., S. I. Makino & T. Endo. 2008. Polymorphism in the deutonymph and adult of Sennertia alfkeni (Acari: Chaetodactylidae) associated with the large carpenter bee, Xylocopa appendiculata circumvolans (Hymenoptera: Apidae). Journal of Natural History.42: 1361-1384.

Oudemans, A. C. 1900. Further notes on Acari. Tijdschrift voor Entomologie.43: 109-128.

Oudemans, A. C. 1901. Notes on Acari. 3d ser. Tijdschrift der Nederlandsche Dierkundige Vereeniging. Leiden.7: 50-87 + plates i-iii.

Oudemans, A. C. 1903. Notes on Acari: Fifth Series. Tijdschrift voor Entomologie.45: 123-150.

Oudemans, A. C. 1905. Acarologische Aanteekeningen XX. Entomologische Berichten.2: 15-23.

Oudemans, A. C. 1924. Acarologische Aanteekehingen LXXVII. Entomologische Berichten (Amsterdam).6: 317-336.

Trägårdh, I. 1904. Drei neue acariden aus Kamerun. Entomologisk Tidskrift.25: 151-160.

Vitzthum, H. 1912a. Ueber einige auf Apiden lebende Milben. Zeitschrift für Wissenschaftliche Insektenbiologie.8: 289-293.

Vitzthum, H. 1912b. Ueber einige auf Apiden lebende Milben. Zeitschrift für Wissenschaftliche Insektenbiologie.8: 231-233.

Vitzthum, H. 1914. 4. Beschreibung einiger neuen Milben. Zoologischer Anzeiger.44: 315-328.

Vitzthum, H. 1919. Acarologische Beobachtungen. 3. Reihe. Archiv für Naturgeschichte.85(Abt. A, no. 5): 1-62.

Vitzthum, H. 1941. Über den Symphorismus einiger unbekannter Tyroglyphiden-Deutonymphen. Zeitschrift fur Parasitenkunde.12: 307-316.

Womersley, H. 1941. Studies in Australian Acarina. (2) Tyroglyphidae (s. l.). Records of the South Australian Museum.6: 451-488.

Zachvatkin, A. A. 1941. Tiroglifoidnue kleshchi Tyroglyphoidea [=Tyroglyphoid mites Tyroglyphoidea]. In Fauna SSSR: Paukoobraznuye, ed. S. A. Zernov, 475. Moscow-Leningrad: Akademiya Nauk SSSR.