Aporcelaimellus		Contents		Rev 09/30/2024
		Classification		Biology and Ecology
		Morphology and Anatomy		Life Cycle
Return to Aporcelaimellus Menu				Ecosystem Functions and Services
		Distribution		Management
Return to Aporcelaimidae Menu		Feeding		References
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Classification:

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Morphology and Anatomy:

The genus Aporcelaimellus is well defined but many of the species were poorly described, especially in earlier literature, and have overlapping morphometric characters (Andrassy, 2010).

• Body length 0.8-3.4 mm; plump.
• Cuticle of two layers differing in refraction; the outer layer transparent and the inner layer less transparent...
• Somatic muscles in tail unusually thick
• Labial region offset from body contour.
• Odontostyle short and thick; aperture about half of odontostyle length.
• Female gonad diovarial, amphidelphic; vulva transverse.
• Intermediate part of vaginal canal with sclerotized walls - pars refringens vaginae.
• Male rare; spicules dorylaimoid; Ventromedian supplements 5-21.
• Tail similar in both sexes; short, conoid rounded to hemispherical; occasionally dorsally concave and subdigitate.
• Inner layer of cuticle usually thicker at tail...

Two species with distinctive atypical features are A. porosus and A. nigeriensis which have a row of coarse ventral body pores throughout the entire body length (Rahidifard et al., 2020).

Aporcelaimellus generally resembles Metaporcelaimus but differs mainly in the morphology of the tail region and in the body width.  In Metaporcelaimus the ratio a (length/width) is usually > 30, that is, most of these species are quite slender.  In Aporcalaimellus the ratio a is more variable, ranging from 19 to 49; that is, some species are slender, others quite robust..  In Metaporcelaimus the tail is conoid with a rounded tip and longer than the abd; it is shorter and more rounded in Aporcelaimellus. Metaporcelaimus is also similar to Aporcella except that the sclerotized pieces in the vagina, the  pars refringens vaginae, is always present.

Ref: Andrassy, 2009; Alvarez-Ortega et al., 2013a,b

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Distribution:

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Feeding:

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Biology and Ecology:

  The duration of each lifestage was influneced by availability of food.  Development was suspemndede when food was not available and resumed when it became available again.

 In a study of the nematode faunae of Florida, USA, McSorley (2012) noted that Eudorylaimus (Qudsianematidae), Aporcelaimellus (Aporcelaimidae)  and Mesodorylaimus (Dorylaimidae) are dominant members of the omnivorous nematode fauna.  They are also reported as dominant in nematode faunae of Europe. The three genera are often found together and multiple species within the genera may be present in slngle soil samples.  In the study, these omnivore nematodes were present in ecosystems that were in nearly all stages of succession but they often reached their greatest numbers in the later stages of succession, such as in soils of old-growth forests. They also showed remarkable adaptation to extreme environments, including Antarctic habitats, dune sands and temperate sites without vegetation. They are reported from a variety of soil types but are limited by soil pH below 4.0. Compared to other nematode taxa, and consistent with their designation of cp 4 and 5 in the Bongers (1990) colonizer-persister system,.they are among the genera most sensitive to moisture levels in sandy soils and to pollution by heavy metals. Some reports also indicate adverse impacts from inorganic fertilisers and other agrichemicals in cultivetd systems.

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Life Cycle:

After developing techniques for laboratory culture, Wood (1973a) observed that at 18-20 C eggs hatched ate 230-250 hours after being deposited, the first stage juvenile molted to the second stage after 14-18 days, the second stage was completed in 16-23 days, the third stage in 26-34 days, the fourth in 25-39 days, with a total generation time of 95-130 days.  All juvenile stages possess primary and replacement odontostyles, the replacement odontosyle located in the musculature of the esophagus; adults posess only the primary odontostyle.

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Ecosystem Functions and Services:

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Management:

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References:

Alvarez-Ortega, S., Pena-Santiago, R. 2013.Taxonomy of the genus Aporcelaimellus Heyns, 1965 (Nematoda, Dorylaimida, Aporcelaimidae). Zootaxa 3669 (3): 243�260

Alvarez-Ortega, S., Subbotin, S., Pena-Santiago, R. 2013. Morphological and molecular characterisation of Aporceleimellus simplex (Thorne & Swanger, 1936) Loof & Coomans, 1970 with a new concept for Aporcella Andrassy, 2002 (Dorylaimida: Aporcelaimidae. Nematology 15:165-178.

Alvarez-Ortega, S., Subbotin, S., Pena-Santiago, R. 2013. Morphological and molecular study of California species of the genus Aporcelaimellus Heyns, 1965 (Dorylaimida, Aporcelaimidae).  Nematology 15:431-449.

Andrassy, I. 2009. Free-living Nematodes of Hungary III.  Hungarian Natural History Museum, Budapest. 608p.

Andrassy, I. 2010. Two new species of Aporcelaimellus (Nematoda: Dorylaimida) from the Americas. Acta Zool. Acad. Sci. Hungaricae. 56:1-8.

Bongers, T. (1990) The maturity index: an ecological measure of environmental disturbance based on nematode species composition. Oecologia 83, 14-19.

McSorley, R. 2012. Ecology of the dorylaimid omnivore genera Aporcelaimellus, Eudorylaimus and Mesodorylaimus. Nematology 14:645-663.

Rashidifard, M., T.T. Bello, H. Fourie, D.L. Coyne and R. Pena-Santiago. 2020. Morphological and molecular characterisation of Aporcelaimellus nigeriensis sp. n. (Dorylaimida: Aporcelaimidae), a remarkable dorylaim from Nigeria. Nematology 22:867-877.

Thorne, G. 1939. A monograph of the nematodes of the superfamily Dorylaimoidea. Capita Zool. 8: 1-263.

Wood, F.H. 1973a. Biology of Aporcelaimellus sp. (Nematoda: Aporcelaimidae). Nematologica 19: 528-537.

Wood 1973b. Feeding relationships of soil-dwelling nematodes. Soil Biol. Biochem. 5:593-601.

Yeates, G.W., T. Bongers, R. G. M. De Goede, D. W. Freckman, and S. S. Georgieva. 1993. Feeding habits in soil nematode families and genera—An outline for soil ecologists. Journal of Nematology 25:315-331

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Copyright © 1999 by Howard Ferris.
Revised: September 30, 2024.