Progamotaenia corniculata, Beveridge & Shamsi, 2009

Beveridge, I. & Shamsi, S., 2009, Revision of the Progamotaenia festiva species complex (Cestoda: Anoplocephalidae) from Australasian marsupials, with the resurrection of P. fellicola (Nybelin, 1917) comb. nov., Zootaxa 1990, pp. 1-29 : 18-19

Progamotaenia corniculata sp. nov.

( Figs 38–43)

Synonyms: Progamotaenia festiva ( Rudolphi, 1819) sensu Beveridge et al. (1992) , Spratt et al. (1991). Host: Lagorchestes conspicillatus Gould (Marsupialia: Macropodidae ). Site in host: bile ducts. Types: Holotype, Inkerman, Queensland (19° 44’S 147° 28’E), coll. P.M. Johnson, 5.x.1971, SAM

29355; 20 paratypes, same data, SAM 20760 (S), 10376 (W), BMNH 2008.3 .6.11 (S). Etymology: corniculata means horned and refers to the structure of the pyriform apparatus .

Material examined: From Lagorchestes conspicillatus (spectacled hare wallaby): Queensland: types; 5 specimens, Inkerman ( SAM 29356 (S), 7162 (W)), fragments of 15 specimens, Rubyvale ( SAM 29357 (S), 10879 (W)); 3 specimens, Blackbraes National Park ( SAM 28946(S), AM 495425 ); fragments, 80 km N of Moorinya ( SAM 28961 (S), AM 495424 ) .

Description: Short, slender worms, 50–106 (73) long, maximum width 2.5–4.0 (3.3) with 158–315 (215) segments in gravid specimens. Scolex small 0.49–0.68 (0.54) in diameter, weakly 4-lobed; suckers circular, 0.146 –0.228 (0.195) in diameter. Neck slender. First mature segment 72–90th (81). Mature segments craspedote, 0.81–1.69 (1.34) wide, 0.14–0.31 (0.19) long. Genital atrium small, in middle of lateral segment margin; cirrus sac elongate, extending well beyond osmoregulatory canals, 0.228 –0.390 (0.302) long, 0.026 –0.065 (0.047) wide; cirrus unarmed; internal seminal vesicle occupies approx. 2/3–3/4 of volume of cirrus sac, 0.085 –0.195 (0.140) long, 0.033 –0.098 (0.060) wide; elongate external seminal vesicle, covered with glandular cells, 0.052 –0.150 (0.081) long, 0.033 –0.059 (0.044) wide, sometimes overlying cirrus sac; vas deferens coils medially, dorsal to uterus; testes arranged in anterior half of segment between osmoregulatory canals; no or very slight space between canals and testis fields; testes arranged in 2–3 dorsoventral layers, usually in single band, less frequently in 2 separate groups; segments with single band or 2 groups occur in same specimen. Testes 0.039 –0.059 (0.048) in diameter; testis number 50–63 (57). Vagina tubiform, lacking glandular investment, opens to genital atrium posterior to cirrus sac, leads to ovoid seminal receptacle 0.078 –0.163 (0.109) x 0.010 –0.098 (0.059). Ovary flabelliform, medial to seminal receptacle 0.046 –0.098 (0.064) x 0.026 –0.065 (0.043); vitellarium reniform, posterior to ovary, 0.065 –0.163 (0.094) x 0.033 –0.072 (0.054); Mehlis’ gland anterior and medial to vitellarium, c. 0.08 in diameter. Uteri paired in each segment, transverse, tubular; early uterus extends from level of ovary to near proximal pole of cirrus sac; developing uterus extends medially and laterally, lateral extensions crossing osmoregulatory canals dorsally; uteri of each segment do not meet in mid-line. Gravid segments 0.195 –0.488 (0.369) long, 1.41–3.41 (2.08) wide. Egg spherical, shell smooth, 0.039 –0.043 (0.041) in diameter; pyriform apparatus conical, with 2 tapering arms, without filaments at apices; oncosphere 0.012 –0.016 (0.014) in diameter. Osmoregulatory canals paired; ventral canal generally wider than dorsal, medial to it; ventral canal 0.020 –0.052 (0.029) in diameter, dorsal canal 0.013 –0.026 (0.016) in diameter; transverse canal connects ventral canal at posterior margin of each segment; accessory canals absent.

Remarks. This species differs from P. festiva in being a small species, 50–106 mm long, with the cirrus sac extending across the osmoregulatory canals, into the medulla. It differs from P. fellicola and P. aemulans in that there is no space between the testis fields and osmoregulatory canals and it differs from these species as well as from P. dilatata sp. nov., P. onychogale sp. nov. and P. pulchella sp. nov. in having an elongate neck.

It also differs from all species of the complex other than P. pulchella in having a pyriform apparatus terminating in two horns rather than in numerous reflexed filaments.