Tetrancistrum, Goto and Kikuchi, 1917

Kritsky, Delane C., Galli, Paolo & Tingbao, Yang, 2007, Dactylogyrids (Monogenoidea) parasitizing the gills of spinefoots (Teleostei, Siganidae): revision of Tetrancistrum Goto and Kikuchi, 1917, with descriptions of two new species from Siganus spp. of the Red Sea and Celebes, Journal of Natural History 41 (25 - 28), pp. 1513-1551 : 1544-1545

Tetrancistrum lebedeIJi Gupta and Sharma, 1982

Type host and locality. Lutjanus johnii: Pamban , Tamil Nadu, India .

Site of infestation. Gills.

Preυious record. No other records except for the original description ( Gupta and Sharma 1982).

Remarks. The type specimens of T. lebedeυi have not survived (N. Agrawal, personal communication) and specimens of the species were not available for study. The original description is incomplete, and the illustrations of the species, which lack sufficient detail for diagnosis, were clearly mixed with those of another dactylogyrid species described in the paper by Gupta and Sharma (1982); their Plate 7, Figure 6 (identified as the haptor of T. lebedeυi) apparently represents the haptor of Pseudohaliotrematoides lutjanusi Gupta and Sharma, 1982 , which they described from Lutjanus lutjanus (Lutjanidae) , while Plate 6, Figure 2 (identified as the haptor of P. lutjanusi ) is that of T. lebedeυi. Their depiction of the copulatory complex of T. lebedeυi (Plate 7, Figure 3 ) resembles that of T. yamagutii ( Figure 36 ), from which it differs by lacking the basal recurves of the shaft of the MCO. Because of the absence of type specimens and the inadequate original description, T. lebedeυi is considered a species inquirenda.

Other dactylogyrid species of concern

In the above revision, Tetrancistrum is restricted to species having tandem gonads (germarium forming a cap over the anterior margin of the haptor) and haptoral anchors with longitudinally striated basal roots. Two dactylogyrid genera, Pseudohaliotrematoides and Pseudancyrocephalus , are considered junior subjective synonyms of Tetrancistrum . These taxonomic actions have resulted in a number of described species previously placed in these genera without formal taxonomic positions. The following brief remarks pertain to the taxonomic status of these species.

Figures

Figures 1–7. Tetrancistrum sigani Goto and Kikuchi, 1917 from the mottled spinefoot, Siganus fuscescens, Great Barrier Reef, Australia. (1) Whole mount (composite, ventral view). (2) Copulatory complex (ventral view, slightly compressed). (3) Copulatory complex (ventral view). (4) Ventral bar. (5) Dorsal bar. (6) Ventral anchor. (7) Dorsal anchor. Scale bar: 400 Mm (1); 30 Mm (2–7).

Figures 35–40. Tetrancistrum yamagutii sp. n. from Siganus sp., Macassar. (35) Whole mount (composite, ventral view). (36) Copulatory complex. (37) Dorsal bar. (38) Ventral bar. (39) Ventral anchor. (40) Dorsal anchor. Scale bar: 200 Mm (35); 30 Mm (36–40).