Notoscolex tasmani (Lee, 1959)

Blakemore, Robert, 2011, Further records of non-cryptic New Zealand earthworms, ZooKeys 160, pp. 23-46 : 32-33

Notoscolex tasmani (Lee, 1959) Fig. 5

Megascolides tasmani Lee, 1959: 313, figs. 326-328.

Megascolides tasmani ; Blakemore, 2004, 2005, 2010; Buckley et al., 2011?

Distribution.

Known only from Great Island, Three Kings Islands. Buckley et al. (2011) claim to have " Megascolides tasmani " (WM82), but this must be a mistake if they could not identify it as clearly belonging in Notoscolex with non-tubular prostates as herein from type inspection (or perhaps they failed to attempt specimen dissections?).

Description from type.

Specimen AMNZ 5039 has the following labels in its jar: "Auckland Museum Coll No. 13 Wet Greywacke gravel. Tasman Stm. Great Island. Three Kings 31.xii.52 J.S. Edwards"; "HOLOTYPE Megascolides tasmani Lee Tasman Stm, Great Is. Col. J.S. Edwards 30/12/52 1021. 3KI3" [note slightly different dates], a further label is blank. Somewhere are two other non-type specimens from the same locality according to Lee’s account ( Lee 1959: 314) with one collected “5.I.53”.

The type specimen is dark and brittle, shrunken to 53 mm long. Lee has 67.5 mm with 132 segments but it is a posterior amputee so must naturally be greater (there is also a slight possibility it acquires more setae posteriorly). Dorsal pores, not noted by Lee, are present from 10/11, at least. It appears lumbricine with widely spread setae that converge slightly towards male pores. Lee has overlooked the penial setae which are protruding (due to shrinkage?) from each of the male pores on 18. In 17 in ab lines is a reddish patch that may be a residual genital artefact. The female and spermathecal pores are no longer obvious. Vascularization is mostly as described by Lee, i.e., commissurals are in 6-9, hearts are in 10-12 from dorsal blood vessel that loops between septa in 11, 12, (not 13) 14, 15 and 16 thereafter single ( Lee 1959: fig. 327 shows only in 14 and 15). Gizzard appears in 6 rather than 5 but being overlain by tufted pharyngeal glands it is difficult to discern. Seminal vesicles are in 9 and 12 as described. Prostates differ significantly as they are flattened tubuloracemose structures, rather than "tubular, convoluted" as Lee has them; the duct is not traceable in the delicate specimen and, moreover, there is a bundle of long reddish penial setae more ventrally. An excised spermatheca is in a separate vial in the jar and, apart from being desiccated, complies with Lee’s (1959) account and figure. The wide intestine contains organic matter and is full of coarse grits of various minerals.

Remarks.

Having non-tubular prostates qualifies this taxon as a new combination in Notoscolex . The remote chance it acquires extra setae posteriorly after cut would permit it in Anisochaeta . Penial setae are unusual for New Zealand Megascolecidae , but it is interesting that they do not correspond well to the length of the spermathecal diverticula (see Blakemore 2000c; 2008). Further investigation is required for confirmation.