Haplodidymos, Hochberg, Rick & Cannon, Lester R. G., 2002

Hochberg, Rick & Cannon, Lester R. G., 2002, Two new freshwater rhabdocoels, Austrodalyellia gen. nov. and Haplodidymos gen. nov. (Platyhelminthes), from Queensland, Australia, Zootaxa 44, pp. 1-15 : 9

Haplodidymos gen. nov.

Type Material. Holotype (QM G219256), de Faure’s wholemount of adult specimens with sclerotic stylet. Paratypes: de Faure’s wholemount of adult with stylet (QM G219257), de Faure’s wholemount of adult with egg (QM G219258), and one sectioned specimen (QM G219259).

Type Repository. Queensland Museum, South Brisbane, Queensland, Australia.

Type Locality. Shoreline of Clean Lake, University of Queensland, St. Lucia campus, Brisbane, QLD.

Etymology. the genus name refers to the presence of a single long testis: Haplo (Gr. single), ­ didymos (Gr. testicle).

Diagnosis. A freshwater typhloplanid worm with anatomical features characteristic of the family Typhloplanidae . Body length 500­720 um long with an anterior pair of large red eyes and short paired tracts of adenal rhabdites. Body is transparent except for several radially­arranged pigment bands. Vertically­oriented pharynx rosulatus in posterior onethird of body. Single, long medial testis ventral to gut. All other male organs are posterior to the pharynx including a copulatory organ with distinct vesicula seminalis and indistinct vesicula granulorum. Within the glandular posterior zone is a slightly curved, weakly sclerotic stylet. Female system posterior to the pharynx and includes a solitary ovary with separate receptaculum seminis, muscular bursa copulatrix, and posterior uterus. All reproductive organs communicate with a single genital atrium and common gonopore.

Type species. Haplodidymos rubroculatus sp. nov. ( Figs. 7­9 )

Etymology. Species name refers to the presence of paired red eyes; rubro (L. red) and oculatus (L. ­eyed).

Figures

FIGURE 7. Haplodidymos rubroculatus gen. nov. sp. nov. Slightly squeezed live specimen. Scale bar = 150 µm. AR, adenal rhabdites; BC, bursa copulatrix; EY, eye; OV, ovary; PB, pigment bands; PH, pharynx; RS, receptaculum seminis; TE, testis; UT, uterus; VI, vitellaria.

FIGURE 8. Haplodidymos rubroculatus gen. nov. sp. nov. Anterior end showing large eyes. Scale bar = 60 µm.

FIGURE 9. A­C. Haplodidymos rubroculatus gen. nov. sp. nov. Reproductive organs. A. ventral view posterior to pharynx. Scale bar = 30 µm. B. Ventral view of fixed holotype. Scale bar = 45 µm. C. Sagital reconstruction of posterior end. Scale bar = 100 µm. BC, bursa copulatrix; CG, caudal glands; CO, copulatory organ; GA, genital atrium; OV, ovary; SR, receptaculum seminis; ST, stylet; TE, testes; UT, uterus; VI, vitellaria; VS, vesicula seminalis.