Angularella sp.

Dronen, Norman O., Blend, Charles K., Gardner, Scott L. & Jiménez, F. Agustín, 2007, Stictodora cablei n. sp. (Digenea: Heterophyidae) from the royal tern, Sterna maxima (Laridae: Sterninae) from Puerto Rico and the Brazos County area of the Texas Gulf coast, U. S. A., with a list of other endohelminths recovered in Texas, Zootaxa 1432 (1), pp. 35-56 : 45

Angularella sp. (Syn. Angularia Clerc, 1906 – preoccupied genus)

( Fig. 5–7 )

Locality: Galveston Bay, Galveston County, Texas, U.S.A., 29 Ο 18' N latitude, 94 Ο 48' W longitude.

Site of infection: Intestine.

Deposited specimens: Voucher specimens (3 specimens) HWML 48508 .

Prevalence: 1 of 4 birds, 25%.

Mean intensity: 4 individuals/infected bird.

Description: Based on 3 complete specimens. Strobilla distinctly craspedote, external strobilization complete. Total length of worms 12,025 (11,500 –13,550) composed of 140–165 proglottids. Scolex 350 (290– 395) by 330 (300–370); rostellum with posterior end embedded in a round globular structure (“glandular rostellar pouch” in key of Bona (1994), 80 (65–95) long; rostellar hooks in groups similar to that illustrated by Schmidt & Neiland [1971]), but with fewer hooks in each group (3 or 4 rows) of irregular-shaped spines, largest spines approximately 12 long, smallest spines approximately 5 long; suckers 125 (120–130) by 125 (115– 140). Neck short. Two longitudinal excretory canals per side, approximately 7–9 in width. Immature proglotttids wider than long, approximately 40 long by 200 wide immediately posterior to scolex; larger immature proglottids located just prior to development of primodia of reproductive glands, 115 (110–125) by 290 (245– 325). Mature proglottids 270 (220–280) by 595 (580–630). Testes large, generally in posterior aspect of proglottids, 28 (20–30) by 32 (20–35), 7–11 poral, 11–15 aporal. Genital pores alternating irregularly. Genital ducts passing between excretory canals. Cirrus sac laterally elongate, 165 (160–170) by 54 (50–55); cirrus finely spined, 75–84 long. Vas deferens anteroporal, highly coiled tubule overreaching midline. Ovary bilobed, occupying most of space between excretory canals, on midline, 214 (190–220) by 370 (350–440). Vagina opening dorsal to cirrus. Seminal receptacle oblique, located in space between ovarian lobes near middle of mature proglottids, 85–95 by 45–55 (N=2). Vitellarium nearly triangular, immediately posterior to seminal receptacle, 80 (65–95) wide. Few gravid proglottids (5–10), 285 (270–290) by 674 (640–690). Uterus saccate; eggs with no polar processes observed, 30–35 in diameter.

Remarks. Species of Angularella Strand, 1928 are typically intestinal parasites of passeriform birds ( Hirundinidae ) ( Bona 1994). There have been several reports of species of this genus in the western hemisphere: Angularella audubonensis Stamper & Schmidt, 1984 has been reported from the cliff swallow, Petrochelidon pyrrhonota Vieillot, 1817 from Colorado, U.S.A. by Stamper & Schmidt, 1984; A. bema (Clerc, 1906) has been reported from the barn swallow, Hirundo rustica Linnaeus, 1758 and the bank swallow, Riparia riparia (Linnaeus, 1758) , from North America ( Schmidt, 1986) and from a mangrove swallow, Tachychineta albilinea (Lawrence, 1863) (syn. Iridoprone albilinea) from El Recreo, Zelaya, Nicuragua by Schmidt & Neiland (1971). The royal tern, S. maxima , is a Charadriiformes , and this finding represents a new host record. This species appears to be undescribed; however, although our specimens are in good condition, we had only 3 complete specimens of Angularella sp. , precluding an adequate species description. The presence of a species of Angularella in a tern rather than a passeriform bird ( Hirundinidae ) suggests the possibility that our specimens may represent a new genus.

Figures

FIGURES 5–9. 5. Angularella sp., Scolex. 6. Angularella sp., rostellum. 7. Angularella sp., dorsal view of mature proglottid. 8. Unknown genus & species of Dilepididae, scolex without rostellar hooks. 9. Unknown genus & species of Dilepididae, dorsal view of mature proglottid. Abbreviations N, neck; O, ovary; R, rostellum; RG rostellar gland; S, seminal receptacle; T, testis; V, vitellarium. Scale bars: 5, 230µm; 6, 60µm; 7, 180µm; 8, 340 µm; 9, 38 µm.