Parasitiformes

Neocarus texanus, copyright Robert Deans.

Belongs within: Euchelicerata.
Contains: Mesostigmata, Ixodida.

The Parasitiformes are a group of usually well-sclerotised mites, many species of which are predatory or otherwise feeders on animal matter (scavengers or parasites). They are characterised by having the respiratory openings at the side of the body, close to the hind pairs of legs; four pairs of dorsolateral stigmata are present in Opilioacaridae but a single ventrolateral pair is present in other Parasitiformes. Earlier authors often treated the Opilioacaridae as the sister taxon to Parasitiformes rather than a member of the Parasitiformes proper, but they are commonly included by recent authors.

Opilioacarids are relatively large, long-legged mites with a leathery integument known from tropical and warm temperate parts of the world. The prodorsum bears two or three pairs of lateral ocelli whereas at most one pair is present in other Parasitiformes, and the opisthosoma bears indications of the ancestral segmentation. Opilioacarids also differ from other Parasitiformes in the presence of a large pair of claws on the palptarsi and the division of trochanters III and IV in tritonymphs and adults (Walter & Harvey 2009).

The remaining Parasitiformes are divided between three lineages whose relationships are uncertain. Recent studies, both morphological and molecular, have suggested that the Holothyrida are more closely related to the Ixodida than to the Mesostigmata but the support for this position is weak (Walter 2009). The Holothyrida are large, heavily sclerotised mites with a relictual distribution in South and Central America and Australasia. Members of the family Neothyridae are found in the Americas whereas Allothyridae and Holothyridae are found in Australasia; Holothyridae are also found on islands in the Indian Ocean (Walter 2009).

<==Parasitiformes [Anactinochaeta, Anactinochitinosi, Anactinotrichida, Gamasiformes, Parastigmata] WH09
    |--Opilioacaridae [Notostigmata, Opilioacarida, Opilioacariformes, Opilioacarina, Opilioacaroidea] WH09
    |    |  i. s.: Phalangiacarus brosseti WH09, WP99
    |    |         Panchaetes WH09
    |    |         Salfacarus WH09
    |    |         Adenacarus arabicus WH09
    |    |         Vanderhammenacarus WH09
    |    |         Gibocellum Stecker 1876 [Gibocellinae] K18
    |    |           `--*G. sudeticum Stecker 1876 K18
    |    |         Neocarus texanus (Chamberlin & Mulaik 1942) WH09, PL17 [=Opilioacarus texanus PL17]
    |    |--+--Paracarus Chamberlin & Mulaik 1942 H02
    |    |  |    `--P. hexophthalmus WH09
    |    |  `--Siamacarus Leclerc 1989 H02
    |    |       `--S. withi S07
    |    `--+--Eucarus With 1904 H02
    |       |    |--E. arabicus With 1904 H02 [=Opilioacarus arabicus S04]
    |       |    `--E. italicus With 1904 H02 [=Opilioacarus italicus S04]
    |       `--Opilioacarus With 1902 H02
    |            |--O. platensis Silvestri 1904 S04
    |            `--O. segmentatus With 1902 [=Eucarus segmentatus] H02
    `--Archicotylea AL37
         |--Mesostigmata W07
         `--+--Ixodida W07
            `--Holothyrida [Holothyriformes, Holothyrina, Holothyroidea, Tetrastigmata] W07
                 |  i. s.: Haplothyrus W09
                 |--Allothyridae W09
                 |    |--Australothyrus van der Hammen 1983 H98
                 |    |    `--*A. ocellatus van der Hammen 1983 H83
                 |    `--Allothyrus Womersley 1961 H98
                 |         |--A. australasiae (Womersley 1935) [=Holothyrus australasiae] H98
                 |         `--A. constrictus (Domrow 1955) [=Holothyrus constrictus] H98
                 `--+--Neothyrus [Neothyridae] W09
                    |    `--N. ana Lehtinen 1981 H83
                    `--Holothyridae W09
                         |--Holothyrus H83
                         |    |--H. armatus Canestrini 1897 H83
                         |    |--H. coccinella Gervais 1842 H83
                         |    |--H. gardineri Warburton 1913 H83
                         |    |--H. legendrei Van der Hammen 1983 H83
                         |    |--H. seychellensis Thon 1906 H83
                         |    `--H. testudineus Butler 1876 H83
                         |--Sternothyrus braueri DW10
                         |--Lindothyrus W09
                         `--Hammenius W09
                              |  i. s.: H. braueri (Thon 1905) [=Holothyrus braueri, Thonius braueri] H83
                              |--H. (Hammenius) H83
                              |    |--H. (H.) fujuge Lehtinen 1981 H83
                              |    |--H. (H.) ingii Lehtinen 1981 H83
                              |    `--H. (H.) niger (Thon 1905) H83
                              |--H. (Leiothyrus van der Hammen 1983) H83
                              |    |--H. (*L.) holthuisi Van der Hammen 1983 H83
                              |    |--‘Holothyrus’ expolitissimus Berlese 1923 H83
                              |    `--H. (L.) nitidissimus (Thorell 1882) (see below for synonymy) H83
                              `--H. (Thonius) H83
                                   |--H. (T.) grandjeani (Van der Hammen 1961) H83
                                   |--H. (T.) longipes (Thorell 1882) (see below for synonymy) H83
                                   `--H. (T.) montanus Van der Hammen 1983 H83

Nomen nudum: Holothyrus gervaisi Thon in Hughes 1959 H83

Hammenius (Leiothyrus) nitidissimus (Thorell 1882) [=Holothyrus nitidissimus; incl. Ho. scutifer Thorell 1882] H83

Hammenius (Thonius) longipes (Thorell 1882) [incl. Holothyrus longipes var. ferrugineus Thorell 1882] H83

*Type species of generic name indicated

REFERENCES

[AL37] André, M., & É. Lamy. 1937. Les Idées actuelles sur la Phylogénie des Acariens. Published by the author: Paris.

[DW10] Dabert, M., W. Witalinski, A. Kazmierski, Z. Olszanowski & J. Dabert. 2010. Molecular phylogeny of acariform mites (Acari, Arachnida): strong conflict between phylogenetic signal and long-branch attraction artifacts. Molecular Phylogenetics and Evolution 56 (1): 222–241.

[H98] Halliday, R. B. 1998. Mites of Australia: A checklist and bibliography. CSIRO Publishing: Collingwood.

[H83] Hammen, L. van der. 1983. New notes on Holothyrida (anactinotrichid mites). Zoologische Verhandelingen 207: 1–48.

[H02] Harvey, M. S. 2002. The neglected cousins: what do we know about the smaller arachnid orders? Journal of Arachnology 30 (2): 357–372.

[K18] Kury, A. B. 2018. Familial nomina in harvestmen (Arachnida, Opiliones). Bionomina 13: 1–27.

[PL17] Pachl, P., A. C. Lindl, A. Krause, S. Scheu, I. Schaefer & M. Maraun. 2017. The tropics as an ancient cradle of oribatid mite diversity. Acarologia 57 (2): 309–322.

[S07] Shultz, J. W. 2007. A phylogenetic analysis of the arachnid orders based on morphological characters. Zoological Journal of the Linnean Society 150 (2): 221–265.

[S04] Silvestri, F. 1904. Note Aracnologiche I–III. Redia 2: 239–261.

[W07] Walter, D. E. 2007. A plethora of questions, but only a modicum of answers: Australian Parasitiformes of tropical forests. In: Morales-Malacara, J. B., V. M. Behan-Pelletier, E. Ueckermann, T. M. Pérez, E. G. Estrada-Venegas & M. Badii (eds) Acarology XI: Proceedings of the International Congress pp. 51–57. Instituto de Biología and Faculdad de Ciencias, Universidad Nacional Autónoma de México, Sociedad Latinoamericana de Acarología: México.

[W09] Walter, D. E. 2009. Order Holothyrida (Holothyrina, Tetrastigmata). In: Krantz, G. W., & D. E. Walter (eds) A Manual of Acarology 3^rd ed. pp. 107–110. Texas Tech University Press.

[WH09] Walter, D. E., & M. S. Harvey. 2009. Order Opilioacarida. In: Krantz, G. W., & D. E. Walter (eds) A Manual of Acarology 3^rd ed. pp. 104–106. Texas Tech University Press.

[WP99] Walter, D. E., & H. C. Proctor. 1999. Mites: Ecology, Evolution and Behaviour. CABI Publishing: Wallingford (UK).

Last updated: 14 March 2020.