Metaphire sedimensis Ng & Panha, 2018

Ng, Beewah, Bantaowong, Ueangfa, Tongkerd, Piyoros & Panha, Somsak, 2018, Description of two new species of the earthworm genus, Metaphire (Clitellata: Megascolecidae), from Kedah, Peninsular Malaysia, Raffles Bulletin of Zoology 66, pp. 132-141 : 133-136

Metaphire sedimensis Ng & Panha , new species

( Fig. 1 ; Table 1)

Material examined. Holotype: One adult ( CUMZ 3672 ), Sedim, Kedah, Malaysia, 5°24′48.6″N, 100°46′51.3″E, coll. B.W. Ng, J.Y. Sam & S.P. Yeap, 23 July 2016. 6 paratypes: 6 adults ( CUMZ 3673 ), 2 adult paratypes deposited at LKCNHM ( ZRC.ANN.0377), same collection data as for the holotype.

Diagnosis. Medium size, length 140–177 mm, diameter 4.67– 5.72 mm at the clitellum, segments 102–111. Prostomium epilobic. First dorsal pore in 12/13. Spermathecal pores small, latero-ventrally paired at intersegment 5/6/7/8/9. Male pores paired in copulatory pouch in XVIII. Genital markings small

Data for a M. songkhlaensis and M. pulauensis are from Bantaowong et al. (2016), b M. malayana from Beddard (1900b), c M. fovella , M. balingensis and M. strellana are from Gates (1949). – = nil. dCommas separate pre- and post-clitellar genital markings.

circular on both spermathecal (on VI, VII, and VIII) and male pore (on XVII and XVIII) regions. Spermathecae four pairs in segments VI–IX, ampulla elongated, club-shaped, with duct shorter than ampulla. Diverticulum with elongated tubular and twisted shape, with oval bulb terminal. Holandric, intestinal caeca simple prostate glands large. Small sessile genital marking glands corresponding to external genital markings.

Description of holotype. External characters. Body length 177 mm, diameter 5.72 mm at clitellum, 102 segments. Prostomium epilobic. First dorsal pore at 12/13. Clitellum annular at XIV–XVI, with no setae. Setal numbering 14–17 in VII, 27 in VIII, 30–40 in XX, 33–38 in X, and 14 between male pores in XVIII. Single female pore at XIV.

Male pores in copulatory pouches, transversely slit-like, conspicuous opening, in XVIII. 0.33 circumference apart ventrally, distance between male pores 5 mm. A pointed penis-like projection within copulatory pouches or everted. Four pairs spermathecal pores, intersegment 5/6–8/9, slit like, 0.67 body circumference ventrally apart, distance between spermathecal pores 10 mm. 1–9 small circular genital markings, post-setal of VI, VII,VIII, XVII and XVIII. Unpaired genital markings, mid-ventral, post-setal of VII and VIII.

Internal characters. Septa, 5/6–7/8 and 12/13/14 thickened, 8/9 and 9/10 aborted. Gizzard large within IX–X. Last heart in XIII. Intestinal origin at XIV. Intestinal caeca originating in XXVI, simple, extending to XXI.

Ovaries paired in XIII. Four pairs spermathecae in VI–IX. Ampulla elongated, club-shaped, with duct shorter than the ampulla. Diverticulum with elongated and twisted slender, oval bulb ampulla. Several genital marking glands, elongated bulb shaped, near spermathecae.

Holandric. Testes sacs paired in X and XI. Seminal vesicles paired in X, XI, and XII. Prostate glands paired in XVIII, racemose, large, occupying segments XVII–XIX. Prostatic duct C-shaped, numerous genital marking glands next to copulatory pouch, sessile corresponding to each external genital markings.

Variation. The holotype length measured 177 mm body length with 102 segments; the 6 paratypes ranged in size from 140–160 mm body length and with 111–118 segments. There is variation in the number of genital markings in the post-setal of VI, VII, VIII, XVII, and XVIII ( Table 2) .

Etymology. This new species was named after the type locality (Sedim).

Distribution. The new species is known only from the type locality.

aSpecimen no. 1 is the holotype, the others are paratypes. Presence is denoted by a plus sign (+), absence is shown with a minus sign (–) and missing data are denoted with a question mark (?).

Habitat. The new species was found inside a ditch covered with sandy loam soil (pH 5.70), at a depth of about 10 cm. The soil surface was covered with thick leaf litter in a forest or near an agricultural area.

Remarks. Metaphire sedimensis new species, belongs to the octothecal group, with spermathecal pores in 5/6–8/9, and with pre- and post-clitellar (postsetal) genital markings in VI–IX and XVII–XVIII. There are six species from Thailand and Peninsular Malaysia that appear to be close to the new species, namely: M. songkhlaensis Bantaowong & Panha, 2016 from Songkhla, Hat Yai; M. pulauensis (Beddard, 1900) from Pulau Bidan, Kedah; M. malayana (Beddard, 1900) from Aring, Kelantan; M. fovella ( Gates, 1949) from Kaki Bukit, Perlis; M. balingensis ( Gates, 1949) and M. strellana ( Gates, 1949) from Baling, Kedah. However, the new species ( Fig. 1 ) is basically smaller in size compared to M. songkhlaensis ( Bantaowong et al., 2016: p. 65, Fig. 2 ) from Hat Yai. Moreover, differences in the number of setae between male pores strongly distinguish these two species. Apparently, the number of setae between male pores is generally lower in M. sedimensis , new species, than in M. songkhlaensis ( Table 1). Metaphire sedimensis , new species, is fairly similar to M. pulauensis ( Bantaowong et al., 2016: p. 67, Fig. 3 ) in terms of its body size and number of segments, but can be distinguished by the pattern of genital markings. Metaphire pulauensis has sieve-like genital markings which are formed by 40–50 pore-like papillae, and are unpaired, mid-ventral, and presetal on VII, VIII, IX, XVII, and XVIII. Metaphire sedimensis , new species, on the other hand, not only has unpaired genital markings, mid-ventral, and postsetal genital markings on VIII, but also has small, circular papillae, and paired postsetal genital markings (c. 1–9) on VI, VII,VIII, XVII, and XVIII.

The external anatomy of M. sedimensis , new species, is very close to M. balingensis ( Gates, 1949: p. 10) , M. malayana (Beddard, 1900: p. 893, Fig. 1 ), M. fovella ( Gates, 1949: p. 21) , and M. strellana ( Gates, 1949: p. 34) but these five species are clearly distinguished from each other by the position of the genital markings. Metaphire sedimensis , new species, differs from M. malayana , M. forella , and M. strellana in the absence of presetal genital markings (present in the latter three species). Postsetal genital markings are

observed in M. sedimensis , new species, and M. balingensis . However, the genital markings of M. balingensis are unpaired and located at the median of VII–VIII, XVI–XIX, whereas the genital markings of the new species are paired on VI– VIII, XVII–XVIII and unpaired on VII, VIII.

Figures

Fig. 1. Metaphire sedimensis new species (holotype). A, external ventral view; B, internal dorsal view; C, enlarged viewed of spermathecae; D, external view, ventrolateral view of left-side of genital marking; E, external view, ventrolateral view of right-side of spermathecae pores.

Fig. 2. Metaphire hijauensis new species (holotype). A, external ventral view; B, internal dorsal view; C, enlarged viewed of spermatheca.

Fig. 3. Molecular affiliation of M. sedimensis new species, and M. hijauensis new species, based on ML analysis of the CO1 DNA barcode sequence, with Pontodrilus litoralis as the out-group. Bar represents the number of nucleotide substitutions per site. Codes before the species name are the museum reference number, whilst those afterwards are the GenBank sequence accession numbers, Jeratthitikul et al. (2017).