Progamotaenia fellicola ( Nybelin, 1917 ) Beveridge, I. & Shamsi, S., 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 : 11-13

Progamotaenia fellicola ( Nybelin, 1917) n. comb.

( Figs 16–23)

Synonyms: Hepatotaenia fellicola Nybelin, 1917 .

Host: Macropus agilis (Gould) (Marsupialia: Macropodidae ).

Types: SMNH 93642-45 , Noonkanbah , Western Australia (18° 31’S 124° 48’E), coll. E. Mjöberg, 31.xi.1911 .

Site in host: bile ducts.

Material examined: From M. agilis (agile wallaby): Western Australia: types, 2 specimens, Beverley Springs Stn via Derby ( SAM 21497, 21489 (S), 7510, 7661 (W)); Northern Territory: 2 specimens, Darwin ( SAM 20794 (S)), 16 specimens, Katherine ( SAM 29851-3 , 29339-40 , 29354 (S), BMNH 2008.6.3.4-5 (S)), 6 specimens, Tipperary Stn ( SAM 9952 , 29344 (S), 9952 (W)), 8 specimens, Elizabeth Downs Stn ( SAM 20841 (S), 10181 (W)); 2 specimens, Mataranka ( SAM 29353 (S)); Queensland: 10 specimens, Townsville ( SAM 29342-3 , 29348 , 29350 (S), 7563, 7575 (W)); 3 specimens, Kelso ( SAM 29352 (S), 34855 (W)); 4 specimens, Oonoonba ( SAM 29345 (S), 7601 (W)), 2 specimens, Yabulu ( SAM 29349 (S), 7494 (W)), 3 specimens, Inkerman ( SAM 29347 (S), 7556 (W)), 1 specimen, Woodstock ( SAM 29341) , 2 specimens, Wenlock River, Cape York Peninsula ( SAM 29346 (S), 7564 (W)); Papua New Guinea: 1 specimen, Bula Plain, Bensbach Province ( SAM 29351 (S)) .

Description: Short, robust worms, 20–75 (47) long, maximum width 2–6 (3.6) with 96–337 (167) segments in gravid specimens. Scolex 0.65–0.89 (0.77) in diameter, squat, mildly 4–lobed; suckers circular, 0.23–0.48 (0.30) in diameter. Neck extremely short or absent. First mature segment 25–45th (34). Mature segments craspedote, 1.54–3.25 (2.31) wide, 0.15–0.33 (0.22) long. Genital atrium small, in middle or slightly posterior to middle of lateral segment margin; cirrus sac elongate, extending well beyond osmoregulatory canals, 0.156 –0.468 (0.200) long, 0.033 –0.111 (0.060) wide; cirrus unarmed; internal seminal vesicle occupies approx. 2/3–3/4 of volume of cirrus sac, 0.091 –0.293 (0.200) long, 0.033 –0.111 (0.060) wide; elongate external seminal vesicle, covered with glandular cells, 0.098 –0.208 (0.150) long, 0.033 –0.072 (0.060) wide; vas deferens coils medially, dorsal to uterus; testes arranged in anterior half of segment between osmoregulatory canals; prominent space between canals and testis fields; testes arranged in 2 dorso-ventral layers, in single band or 2 separate groups; segments with single band or 2 groups occur in same specimen. Testes 0.033 –0.065 (0.040) in diameter; testis number 73–95 (88). Vagina tubiform, lacking glandular investment, opens to genital atrium posterior to cirrus sac, leads to ovoid seminal receptacle 0.078 –0.293 (0.200) x 0.078 –0.260 (0.150). Ovary very small, flabelliform, medial to seminal receptacle 0.052 –0.228 (0.100) x 0.033 –0.104 (0.060), fully developed in only 4–8 segments, involutes within 2 segments of achieving full size; vitellarium reniform, posterior to ovary, 0.098 –0.228 (0.140) x 0.065 –0.130 (0.090); 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 0.228 –0.520 (0.340) long, 1.54–3.54 (2.69) wide. Egg spherical, shell smooth, 0.045 –0.065 (0.054) in diameter; pyriform apparatus conical, terminating in numerous fine filaments at apex; oncosphere 0.015 –0.023 (0.020) in diameter. Osmoregulatory canals paired; ventral canal generally wider than dorsal, medial to it; ventral canal 0.013 –0.033 (0.020) in diameter, dorsal canal 0.010 –0.026 (0.020) in diameter; transverse canal connects ventral canal at posterior margin of each segment; accessory canals absent.

Remarks. This species was first described by Nybelin (1917) under the name Hepatotaenia fellicola , based on specimens collected from Macropus agilis in the Kimberley region of Western Australia. It has subsequently been treated as a synonym of P. festiva (for summary, see Beveridge 1976) being reported from the same host in the Northern Territory ( Beveridge 1976) and Queensland ( Speare et al. 1983). Allozyme studies ( Baverstock et al. 1985) suggested that cestodes from M. agilis from Queensland were genetically distinct from those found in other macropodid hosts (other than for one specimen collected from M. dorsalis ) and these findings were confirmed using DNA- based methods which found no differences between specimens from the Northern Territory and Queensland ( Beveridge et al. 2007). In the latter study, all specimens collected from M. dorsalis were genetically distinct from those found in M. agilis , casting some doubt on the earlier allozyme study by Baverstock et al. (1985).

Progamotaenia fellicola is distinguishable from P. festiva in having a quadrangular scolex with either no neck or an extremely short neck in fully relaxed specimens, in having the first mature segment occur in segments 25–45, in the cirrus sac invariably extending across the osmoregulatory canals, well into the medulla, and in having a distinct space between the osmoregulatory canals and the lateral extremities of the testis fields. In this species, the occurrence of segments with testes arranged in two groups or a single band within the same strobila is commonly observed. However, where two groups of testes are present, the space between them is small. This species is most similar to P. aemulans sp. nov. from Macropus dorsalis , described below The differentiation of these two species is discussed following the description of the new species.