Metaphire paiwanna var. liliumfordi, Tsai & Tsai & Liaw, 2000

Tsai, C. - F., Tsai, S. - C. & Liaw, G, 2000, Two new species of protandric pheretimoid earthworms belonging to the genus Metaphire (Megascolecidae: Oligochaeta) from Taiwan, Journal of Natural History 34, pp. 1731-1741 : 1734-1736

Metaphire paiwanna var. liliumfordi subsp. nov.

(®gure 3)

Type material

HOLOTYPE: A mature specimen (dissected) collected 16 August 1998 from Mt Setou in the middle of the Coastal Mountain Range in eastern Taiwan, Hualien Prefecture (®gure 1) by C. F. Tsai, S. C. Tsai, G. J. Liaw and M. H. Lin (coll. no. 1998-57).

PARATYPES: Two mature specimens (one dissected and one posterior amputated; same collection of holotype).

Other material

A mature specimen collected 12 August 1998 from mountain slope along Chiako Road near Tungho at the southern end of the Coastal Mountain Range , Taitung Prefecture (®gure 1) by C. F. Tsai, S. C. Tsai and G. J. Liaw (coll. no. 1998-54) .

Characters

The subspecies liliumfordi is easily distinguishable from var. typica primarily in male pore structure. The former is S-shaped, and has a skin cover extending medially from lateral wall and a large, smooth oval pad between the horizontal ridge and the anterior end of the pore (®gure 3A), whereas the latter is C-shaped or slightly S-shaped, the skin cover is either absent or very small, and the oval pad is absent (®gure 2A). Also, liliumfordi is larger and heavier, and has a greater number of setae and segments, wholly dark bluish brown clitellum, longer spermathecal and diverticular stalks, and brown and wrinkled caecae ( table 1; ®gure 3B, C).

On the other hand, liliumfordi shares most of the characters with var. typica : four pairs of spermathecae in VI ±IX with spermathecal pores in 5/6±8/9, male pore bordered laterally by thick longitudinal wall and medially by a male disc with horizontal ridge, no genital papillae in both male pore and spermathecal pore regions, a pair of testis sacs in X, a pair of seminal vesicles in XI, septa 5/6±7/8 thickened, septa 8/9 and 9/10 absent, septa 10/11± 13/14 greatly thickened, cylindrical gizzard in VIII and X with a slightly constriction at 9/10, and racemose prostate gland with a short and slightly curved duct.

Locality and habitat

The type specimens were collected from a drainage ditch of a commercial daylily ( Hemerocallis aurantiac a Baker) plantation at an elevation of about 800 m. The ditch was about 50 cm deep, and its bottom was composed of clay. It was fairly wet at the time of collection in the dry summer.

Remarks

Metaphire paiwanna sp. nov. has a pair of C-shaped or S-shaped male pores, each with a speci®c male disc with a horizontal ridge coiling laterally into the copulatory pouch. This character resembles those of Pheretima swanus Tsai of Taiwan ( Tsai, 1964) and Pheretima aggera Kobayashi of Korea ( Kobayashi, 1934) and Manchuria ( Kobayashi, 1940). In the original descriptions, there was no mention of a copulatory pouch in P. swanus ( Tsai, 1964) , but a mention of`a shallow copulatory chamber’ in P. aggera ( Kobayashi, 1934) . Sims and Easton (1972) assigned P. swanus to the genus Amynthas , and P. aggera to the genus Metaphire .

Amynthas swanus has a male disc only slightly coiled into the copulatory pouch, whereas in M. aggera the male disc is completely embedded within the copulatory pouch and covered by the lateral wall. In this respect, one may consider that A. swanus is a primitive form, M. aggera is a specialized form, and M. paiwanna sp. nov. is an intermediate form between the two nominal species. These three species possess the character of male pores with a similar trend in evolution but at diOEerent levels of specialization. They should be accommodated as closely related species within the genus Metaphire . We suggest transferring A. swanus to the genus Metaphire .

This large mountain-dwelling earthworm has been used by the native` Paiwan Tribe’ in the southern tip of Taiwan as bait for the eel ( Anguilla marmorata) ®shery in streams. The name `paiwanna ’ is given to the species to express our appreciation to the native people who introduced this species to us in our earthworm survey. The name `liliumfordi ’ is given to the subspecies to indicate its type locality at the daylily plantation .