Omori M., Vervoort W., 1986: Observations on a living specimen of the giant hydroid branchiocerianthus imperator. 5 pp. Zoologische Mededelingen 60(16): 257-261.

 Ono H., 1986: Spiders of the families Clubionidae, Gnaphosidae and Thomisidae from the Noto Peninsula and the southern part of Ishikawa Prefecture, Japan. 8 pp. Memoirs of the National Science Museum 19: 167-174.

 Ono H., 1993: Spiders of the genus Clubiona (Araneae, Clubionidae) from Eastern Hokkaido, Japan. 6 pp. Memoirs of the National Science Museum 26: 89-94.

 Ono H., Hishikawa Y., 1989: Taxonomic revision of the Heptathelid spiders (Araneae, Mesothelae) from Amami-Ôshima Island, the Ryukyus. 7 pp. (in Japanese). Memoirs of the National Science Museum 22: 119-125.

 Ono H., Shinkai E., 1988: Notes on the Japanese sandy-beach spider, Lycosa ishikariana (Araneae, Lycosidae), based upon fresh topotypical speciemens. 5 pp. Memoirs of the National Science Museum 21: 131-135.

 Ono H., Tanikawa A., 1990: A revision of the Japanese spiders of the genus Langbiana (Araneae, Zodariidae). 12 pp. Memoirs of the National Science Museum 23: 101-112.

 Oplotna H., Rajski A., 1983: Oppiella rafalskii sp. n. (Acarida, Oribatida). 19 pp. [M18] [M54] Acta zoologica cracoviensia 26/16: 543-562.

 Opresko D. M., 2001: Revision of the Antipatharia (Cnidaria: Anthozoa). Part I. Establishment of a new family, Myriopathidae. 28 pp. Zoologische Mededelingen Leiden 75(17): 343-370.

 Opresko D. M., 2004: Revision of the Antipatharia (Cnidaria: Anthozoa). Part IV. Establishment of a new family, Aphanipathidae. 31 pp. Zoologische Mededelingen Leiden 78: 209-240.

 Opresko D. M., 2005: New genera and species of antipatharian corals (Cnidaria: Anthozoa) from the North Pacific. 37 pp. Zoologische Mededelingen Leiden 79 (2): 129-165.

 Opresko D. M., 2006: Revision of the Antipatharia (Cnidaria: Anthozoa). Part V. Establishment of a new family, Stylopathidae. 30 pp.  Zoologische Medelingen 80(4): 109-138.

 Opyrchalowa J., Sadkowska H., 1962: Wystepowanie kedzierzawki plaszczyncowej – Beta virus 3 (Wille) Smith oraz zóltaczki wirusowej – Beta virus 4 (Roland et Quanjer) Smith na burakach cukrowych, jako wskaznik pojawu plaszczynca burakowego – Piesma quadrata Fieb., i mszycy burakowej – Aphis fabae Scop., w województwie wroclawskim w r. 1961. 11 pp. 

 Oshiro L. M. Y., 1999: Aspectos reprodutivos do caranguejo guaia, Menippe nodifrons Stimpson (Crustacea, Decapoda, Xanthidae) da Baía de Sepetiba, Rio de Janeiro, Brasil. 8 pp. Revta bras. Zool. 16(3): 827-834.

 Ossiannilsson F., 1966: Making permanent fluid mounts of minute arthropods. 5 pp. (in English). Entomologisk Tidskrift 87(1-2): 1-4.

 Oštrec L., 1971: Fauna Oribateia u oraničnim tlima istočne Hrvatske. (I prilog poznavanju Oribateia Hrvatske). 6 pp. 

 Oštrec L., 1975: Oribatide u šumskim tlima borovca (Pinus strobus). 5 pp. 

 Oudemans A. C., 1910: Notes on Acari. XIXth series. (Acaridae). 18 pp. 

 Oudemans A. C., 1926: Chorioptes caprae (Del. Bourg. 1858). 22 pp. 

 Oudemans A. C., 1936: Neues über Pediculoides Targ. Tozz. 1878. 14 pp. 

 Ovtsharenko V. I., Fet V. Ya., 1980: Fauna and ecology of spiders (Aranei) of Badhyz (Turkmenian SSR). 6 pp. (in Russian). Entomologitsheskoe obozrenie 59(2): 442-447.

 Ovtsharenko V. I., Marusik J. M., 1990: Taksonomičeskie zamečanija o paukach (Aranei), opisannych A. Grube. 4 pp. 

 Ovtsharenko V. I., Saveljeva L. G., 1990: Analiz fauny paukov semějstva Gnaphosidae Vostočnogo Kazachstana. 3 pp. 

 Paclt J., 1951: Contribution a l’etude de notre faune de domaine principalement endoge. I. 4 pp. (in Czech). 

 Paclt J., 1951: Contribution a l’etude de notre faune de domaine principalement endoge. I. 4 pp. (in Czech). [EVE 551] Folia entomologica 14: 161-164.

 Paladian G., 1965: Some Chromadoridae (free-living Nematoda) from the rocky facies of the Black Sea (Rumanian shore). 6 pp. 

 Paladian G., Lazarescu D., Muresan A., 1968: Biological effects of water-courses pollution of the Ialomita hydrographic basin. 6 pp. 

 Palmén E., 1946: Die Landisopoden Finnlands. 35 pp. 

 Palmén E., 1946: Zwei aus Finnland bisher unbekannte Synanthrope Land-Isopoden. 2 pp. 

 Palmén E., 1951: A survey of the Oniscoidea (Isopoda terr.) of Newfoundland. 27 pp. 

 Palmén E., 1954: Seasonal occurrense of Ephyrae and subsequent instars of Aurelia aurita (L.) in the shallow waters of Tvärminne, S. Finland. 9 pp. (in English). Arch. Societatis Zoologicae Botanicae Fennicae Vanamo: 123-131.

 Palmén E., Rantala M., 1954: On the life-history and ecology of Pachymerium ferrugineum (C. L. Koch) (Chilopoda, Geophilidae). 44 pp. 

 Pande Y. D., Berthet P., 1975: Observations on the vertical distribution of soil Oribatei in a woodland soil. 17 pp. 

 Pankratova V. J., 1959: Litshinki tendipedid nekotorych rek Krasnodarskogo kraja. 10 pp. 

 Paoletti M. G., Stinner B. R., 1989: Two new terrestrial Isopoda (Oniscidea) from coralline cays of Venezuela’s Caribbean coast. 10 pp. Proc. Entomol. Soc. Wash. 91(1): 71-80.

 Parapar J., O’Connor B, Urgorri V., Besteiro C., 1993: Primera cita de Glycera dayi O’Connor, 1987 (Polychaeta, Glyceridae) en las costas ibéricas (2 fig.). [First record of Glycera dayi O’Connor, 1987 (Polychaeta, Glyceridae) from the Iberian coasts.] 4 pp. Bol. R. Soc. Esp. Hist. Nat. (Sec. Biol.) 90(1-4): 43-46.

 Paraskiv K. P., 1953: Semiretshenskij triton (Ljagushkozub). 10 pp. 

 Parent B., 1967: Population studies of Phytophagous mites and predators on apple in southwestern Quebec. 8 pp. 

 Park C. K., Atyeo W. T., 1971: The species of a new subfamily of feather mites, the Allodectinae (Analgoidea: Proctophyllodidae). 26 pp. 

 Parth M., 1990: Bursa muehlhaeusseri, spec. nov. und Bursa angioyorum, spec. nov., zwei neue Bursiden von den Philippinen (Gastropoda, Bursidae). 5 pp. Spixiana 13(2): 217-221.

 Parth M., 1991: Cymatium fittkaui, spec. nov., eine neue Art von den Philippinen. 3 pp. Spixiana 14(2): 205-207.

 Parth M., 1991: Einige Bemerkungen zur Bursa latiduo- und Bursa ranelloides-Gruppe und zur Protochonch von Bursa condita, Gmelin, 1791. 4 pp. Spixiana 14(2): 209-212.

 Parth M., 1992: Colubraria rolli, spec. nov., a new species from Transkei and Natal, South Africa (Mollusca, Gastropoda, Buccinidae). 3 pp. Spixiana 15(3): 299-301.

 Parth M., 1993: Namensänderungen in der Untergattung Ranularia Schumacher, 1817 der Gattung Cymatium Röding, 1798 (Mollusca, Gastropoda, Ranellidae). 7 pp. Spixiana 16: 71-77.

 Parth M., 1994: Eine neue auffällige Turriden-Art von den Philippinen (Mollusca, Gastropoda, Turridae). 2 pp. [MOL96] Spixiana 17(1): 55-56.

 Parth M., 1994: Metula kilburni, spec. nov., eine neue Art von Northwestaustralien (Mollusca, Gastropoda, Buccinidae). 3 pp. [MOL97] Spixiana 17(1): 51-53.

 Parth M., 1996: Beschreibung einer neuen Burside von den Philippinen sowie Bemerkungen zur Systematik in der Familie Bursidae (Mollusca, Gastropoda, Bursidae). 7 pp. Spixiana 19: 129-135.

 Parth M., 1996: Description of a new buccinid species from Vietnam (Mollusca, Gastropoda, Buccinidae). 2 pp. [MOL98] Spixiana 19(3): 301-302.

 Parth M., 1996: Description of a new ranellid species from the Indo-Pacific (Mollusca, Gastropoda, Ranellidae). 2 pp. (in German). [MOL99] Spixiana 19(3): 303-304.

 Parth M., Philippe R., 1992: Spondylus somalicus, spec. nov., a new species from Somalia (Mollusca, Bivalvia, Spondylidae). 2 pp. Spixiana 15(1): 107-108.

 Paspalev G., Željaskova-Paspaleva A., 1965: Untersuchungen über die Helminthenfauna bei Wildvögeln in Thrakien. I. Trematoden. 46 pp. (in Bulgarian).