Pritchardia, Scott L. Gardner & F. Agustín Jiménez & Mariel L. Campbelll, 2013

Scott L. Gardner, F. Agustín Jiménez & Mariel L. Campbelll, 2013, Pritchardia boliviensis N. Gen., N. Sp. (Anoplocephalidae: Linstowinae) a tapeworm from opossums (Didelphidae) in the yungas and lowlands of Bolivia and Atlantic forest of Paraguay, Occasional Papers, Museum of Texas Tech University 319, pp. 1-8 : 3-4

Pritchardia n. gen.

Generic Diagnosis.— Anoplocephalidae, Linstowiinae. Strobilae very small, apolytic, with maximum of 3 acraspedote segments. First segment not conspicuously divided from scolex. Genital Anlagen visible in first developing segment, 2nd proglottid mature, 3rd proglottid gravid, longer than wide. Scolex with 4 unarmed suckers. Neck absent. Cirrus with rugose covering of minute spines. Vas deferens long and coiled, extending from external seminal vesicle to pyriform cirrus sac. External seminal vesicle present. Testes occupying medial part of segment mostly anterior to ovary. Ovary diffuse and reticulate, located posterior to cirrus sac in posterior 1/2 of proglottid gen- erally on the poral side of the segment, never crossing osmoregulatory canals. Vitellarium diffuse, located near posterior margin of mature proglottid. Uterus ephemeral, forming egg capsules, each with a single egg. Vagina entering genital atrium dorsally, extending antiporad from atrium posteriad toward seminal receptacle. Seminal receptacle not overlapping cirrus sac and always anterior to or at same level as anteriormost ovarian follicles. Genital pores alternating regularly. Genital ducts cross excretory canals ventrally.

Taxonomic Summary

Etymology.— Pritchardia is named after Dr. Mary Lou Pritchard, former curator of the HWML Parasite Collection and director of the Harold W. Manter Laboratory of Parasitology, the University of Nebraska State Museum. Dr. Pritchard established the H. W. Manter Laboratory after the untimely death of Dr. Harold. W. Manter in 1971. The generic name is used as feminine.

Diagnosis.— Pritchardia n. gen. is established to include species of cestodes that have an unarmed rostellum, unarmed suckers, suckers that are not covered in pockets of tissue and have compact vitellaria, a diffuse reticulate ovary, minute strobila, and eggs in capsules. The new genus is assigned to the Anoplocephalidae : Linstowiinae because eggs occur in capsules scattered throughout the medullary parenchyma of the gravid segment of each cestode; each egg capsule contains a single egg. In gravid segments, eggs are located only in the central medulla.

Species of Pritchardia can be recognized as distinct from other species included in the 13 genera of the Linstowiinae as follows: absence of lappets on suckers and single set of genitalia per segment while species in Tupaiataenia Schmidt and File 1977 and Panceriella Stunkard 1969 are characterized by having lappets and double genitalia, respectively. The diffuse vitellarium located in the posterior part of the segment distinguishes species in the new genus from three other genera including Linstowia Zschokke 1899 and Echidnotaenia Beveridge 1980 , in which the vitellarium is elongated, and from Gekkotaenia Bursey, Goldberg and Kraus 2005 , which has both the vitellarium and ovary in a poral position. Testes in Pritchardia n. gen. are located anterior to the vitelline gland and lateral to the diffuse, reticulate ovary, contrasting with the antiporal testes in Gekkotaenia and with the arrangement of testes divided in two lateral groups in both Cycloskrjabinia Spasskii 1951 and Witenbergitaenia Wertheim, Schmidt and Greenberg 1986 . Pritchardia n. sp. have testes lateral to and anterior to the ovary which contrasts to the arrangement in species of Atriotaenia Sandground 1926 , Oochoristica Lühe 1898 , and Semenoviella Spasskii 1951 . In Pritchardia n. gen., all proglottids are acraspedote in contrast to the craspedote nature of Atriotaenia , Witenbergitaenia , Paralinstowia Baer 1927 , and Mathevotaenia Akhumyan 1946 . Lastly the genital ducts pass ventrally to the osmoregulatory canals while species of Sinaiotaenia Wertheim and Greenberg 1971 have genital ducts passing between osmoregulatory canals.

Pritchardia n. gen. shares several characters with species described in the genus Paralinstowia . However, species of Pritchardia have much smaller strobilae, fewer testes, a shallower genital atrium, ovoid to pyriform cirrus sac, well developed seminal receptacle, and an external seminal vesicle located at the extreme distal end of a convoluted seminal duct. In addition, the ovary in Pritchardia is reticulate in nature and the vitelline gland is diffuse this is in sharp contrast to the compact vitelline gland and tight bilobed ovaries of species of Paralinstowia . Finally, proglottids are acraspedote in Pritchardia and strongly craspedote in Paralinstowia .