Drawida glabella Chen, 1938
Dr. barwelli
Dr. barwelli
Drawida
Dr. barwelli
Drawida
Dr. barwelli
Dr. barwelli
Dr. barwelli
Dr. glabella
Dr. barwelli
Dr. barwelli
Dr. glabella
Dr. barwelli
Drawida beddardii ( Rosa, 1890 )
Dr. barwelli
Dr. beddardii
Dr. barwelli
Dr. glabella
Dr. glabella
Dr. barwelli
Drawida cf. barwelli
Dr. barwelli
Drawida bahamensis ( Beddard, 1893 )
Dr. barwelli ( Easton 1984 )
Dr. barwelli
Dr. eda
Drawida
Dr. alishanensis
Dr. beddardii
Dr. fluviatilis Stephenson, 1924
Dr. delicata Gates, 1962
Dr. tenellula Gates, 1962
Dr. affinis Stephenson, 1917
Dr. ramnadana Michaelsen, 1907
Dr. willsi Michaelsen, 1907
Dr. fakir Cognetti, 1911
Dr. brunnea Stephenson, 1915
Dr. paradoxa Rao, 1921
Dr. fluviatilis
Dr. delicata
Dr. tenellula
Dr. affinis
Dr. ramnadana ( Michaelsen 1909 )
Dr. willsi ( Michaelsen 1909 )
Dr. brunnea
Dr. paradoxa
Dr. alishanensis
Dr. beddardii
Dr. alishanensis
Dr. fluviatilis
Dr. beddardii
Drawida fakir Cognetti, 1911
Dr. alishanensis
Dr. alishanensis
Dr. fakir
Dr. alishanensis
Drawida
Two new earthworm species of the genus Drawida (Oligochaeta: Moniligastridae) from southwestern Taiwan
Shen, Huei-Ping
Chang, Chih-Han
Chih, Wen-Jay
Zootaxa
2018
2018-10-05
4496
1
302
312
Shen & Chang
Shen & Chang & Chih
2018
[151,605,1518,1544]
Clitellata
Moniligastridae
Drawida
GBIF
Animalia
Haplotaxida
1
303
Annelida
species
alishanensis
sp. nov.
Holotype:Clitellate (mature) specimen ( 50 mmin total length, dissected), Zhuqi, from roadside ditches around a parking lot at south end of a hiking trail in Longyun Farm, 23°28'57.87''N, 120°42'00.62''E, 1486 masl, 28 April 2014, H.-T. Fang (TESRI-O-H-51; Ali046). Paratypes:5 clitellates [one amputated (Ali010) and one dissected (Ali009, PCR failed)], Alishan, from roadside slopes and ditches around Dinghu, 23°29'25.28''N, 120°43'16.77''E, 1661 masl, 25 July 2013, H.-T. Fang (TESRI-O-P-46). Other material.1 clitellate, same collection data as holotype (TESRI-O- 2014-8-7).
Diagnosis.Small, length 35–50 mm, weight 0.08–0.14 gin 95% ethanol, diameter 2.3–2.6 mm. Segments numbering 85–95. Prostomium prolobous. Dorsal pores absent. Setae lumbricine, short and closely paired. Clitellum in X–XIII, swollen, paler than rest of the body. Spermathecal pores one pair in 7/8. Penes usually wholly concealed or slightly visible externally. Secondary male aperture not visible or slit-like in 10/11. Female pores minute, hardly visible, one pair on anterior-most border of XII, each pore in line with seta b. Genital markings absent. Gizzards two in XII–XIII. Testis sacs one pair, large, each suspended on septum 9/10. Sperm duct short, slightly curved. Male atrium follicular, cotton-like, transversely elongated oval-shaped. Spermathecae one pair. Ampulla small, oval-shaped, with slender, coiled duct. Spermathecal atrium small, oval-shaped. Accessory glands absent.
Description.External: Length 35–50 mm(amputated specimen not included), weight 0.08–0.14 gin 95% ethanol, diameter 2.3–2.6 mm. Segments numbering 85–95. Prostomium prolobous. Dorsal pores absent. Setae lumbricine (eight setae per segment), short and closely paired, ab = cd, aa = bc, aa Ề6 ab, dd greater than 0.5 body circumference. Clitellum in X–XIII, swollen, paler than rest of the body. Spermathecal pores one pair in 7/8, each pore small, slit-like, edge slightly wrinkled, medial to seta c. Penes usually wholly concealed in retracted condition ( Fig. 1A) or slightly visible externally ( Fig. 1B). Secondary male aperture not visible or slit-like in 10/11. Female pores minute, hardly visible, one pair on anterior-most border of XII, each pore in line with seta b. Genital markings absent. Preserved specimens grayish or pale gray, and paler or pink around clitellum. Internal: Septa 5/6–8/9 thick and muscular, 9/10 thin. Gizzards two in XII–XIII, round, white, muscular and shining. Hearts four pairs in VI–IX. Nephridia holoic. Testis sacs one pair, large, white or yellowish white, elongated oval-shaped, each suspended on septum 9/10, 0.9–1.5 mmin length and 1.16–1.45 mmin width. Sperm duct short, slightly curved, entirely confined to segment X, entering the upper right side of the male atrium ( Fig. 1D). Male atrium white, follicular, cotton-like, transversely elongated oval-shaped, about 0.35 mmin length and 0.55–0.75 mmin width. Ovarian chamber formed by septa 10/11 and 11/12, meeting in front of the gizzard on dorsal side. One pair of follicular, yellowish ovisacs dorso-lateral on both sides of the digestive tract, occupying the entire compartment of segment XII. Spermathecae one pair, ampulla posterior while spermathecal atrium anterior to septum 7/8. Ampulla small, oval-shaped, 0.62–0.75 mmlong and about 0.5 mmwide, its duct long, slender, with two coils and a loop and then becoming straight to join the spermathecal atrium ( Fig. 1C). Atrium small, ovalshaped, about 0.3 mmlong. Accessory glands absent. DNA barcodes.GenBank accession numbers MH 051135(Ali046, holotype) and MH 051134(Ali010, paratype).
Etymology.The name alishanensisis given to this species with reference to its typelocality in the Alishan area, Chiayi, southwestern Taiwan.
Remarks.In contrast to the long, twisted sperm ducts of Dr. japonica, Dr. koreana, Dr. beiganicaand Dr. dongyinicareported from Taiwanand Matsu( Shen et al. 2015), the simple structure of sperm duct of Drawida alishanensis sp. nov.distinguishes it from all the above species. In addition, when compared with all 41 species and subspecies of Drawidafrom East Asialisted in Blakemore et al. (2014), Dr. alishanensisis fairly similar to Drawida barwelli( Beddard, 1886), Drawida nepalensis Michaelsen, 1907, Drawida syringa Chen, 1933, Drawida keikiensis Kobayashi, 1938, Drawida moriokaensis Ohfuchi, 1938, Drawida tairaensis Ohfuchi, 1938, Drawida omeiana Chen, 1946, and Drawida edaBlakemore, 2010in the small body size and lack of papillae or genital markings. However, sperm ducts of Dr. barwelli, Dr. nepalensis( Michaelsen 1909), Dr. moriokaensis, Dr. tairaensis, Dr. omeiana, and Dr. edaare long and coiled. Chen (1933)did not describe the sperm duct of Dr. syringain detail but mentioned a short, broad, warty male atrium with thick glandular layer and very long, conspicuous egg sacs (ovisac) extending over 10–15 segments. These two characters are apparently disparate from those of Dr. alishanensis. Besides, Dr. syringais slightly larger than Dr. alishanensiswith 50–100 mmin length and 2.5–3.0 mm in width and has 124–172 segments ( Chen 1933). The position of the spermathecal atrium of Dr. syringais also different from that of Dr. alishanensiswith the former posterior to septum 7/8 and the latter anterior to it. As to Dr. keikiensis, its short sperm duct wholly behind septum 9/10 with only a few twists described in Kobayashi (1938)is akin to that of Dr. alishanensis. It differs from the new species in the same characters as Dr. syringa. In fact, we consider Dr. keikiensisto be a junior synonym of Dr. syringa. The description of Dr. keikiensiswas based on two semi-mature specimens from Korea( Kobayashi 1938). Their body size (40 and 54 mmin length and greatest diameter 2.5 mm), segment number (154 and 138) and number of gizzards (three or four in XIII–XV or XII–XV) are within the species range of Dr. syringeof which a total of 68 specimenswere collected from Zhejiang(= Chekiang) Province, central China( Chen 1933). Like Dr. syringa, Dr. keikiensisalso has short penis, short and broad prostate (= male atrium) with a highly warty surface, long ovisacs in XII–XVI (shortest) or XII– XXII (longest), large ampulla, and spermathecal atrium posterior to septum 7/8 ( Kobayashi 1938). Although Kobayashi (1938, p. 110)states in the Remarksthat Dr. keikiensisdiffers from Dr. syringa“mainly in shape of penis and probably also in the structure of the other parts of the male organs, and in position where the sperm-duct enters into the atrium”, he also indicates that “where the sperm-duct enters into the prostate was not decidedly determined” ( Kobayashi 1938, p. 108). When the structures of penis, spermatheca and male atrium and penis pouch illustrated in Chen (1933, Fig. 7)and Kobayashi (1938, Fig. 4)are compared, it is found that they are not distinguishable. Consequently, Dr. keikiensisis considered to be synonymous with Dr. syringa. The other four species of Drawidalisted in Kobayashi (1938), Dr. japonica, Drawida gisti Michaelsen, 1931, Drawida nemora Kobayashi, 1936and Dr. koreana, are also species commonly found in Chinaand Korea.
Drawida glabella Chen, 1938from HainanIsland, Chinais also small sized with a body length of 52 mmand diameter 2 mm. It has no genital papillae or other markings except the swollen lips around the secondary male apertures ( Chen 1938). Blakemore (2010), Blakemore and Kupriyanova (2010)and Blakemore et al. (2014)synonymized this species with Dr. barwelli. Nevertheless, the structures of spermatheca and male organs as shown in Chen (1938, Fig. 1)and in Blakemore and Kupriyanova (2010, Fig. 1.1)are different. Sizes of the ampulla and the spermathecal atrium in Chen (1938, Fig. 1A)are almost the same while ampulla is apparently larger than spermathecal atrium in Blakemore and Kupriyanova (2010, Fig. 1.1e). The larger ampulla together with the smaller spermathecal atrium of Dr. barwelliis also shown in Shen (2018, Fig. 1E). The sperm duct in Chen (1938, Fig. 1B)is with a few loose coils in front of septum 9/10 and rather straight behind to join a roundish and smooth male atrium, whereas in Blakemore and Kupriyanova (2010, Fig. 1.1c), the sperm duct is heavily twisted with a short, straight distal end connecting to a small, follicular prostate (= male atrium) linking to a round, globular copulatory chamber. Fig. 8 of Drawidasp. 3 in Shen and Yeo (2005)shows exactly the same structure characteristic of Dr. barwelliand thus, the identity of this immature specimen of Drawidasp. 3 should be Dr. barwelli. Such a structure of a small, follicular prostate together with a round, globular copulatory chamber typical of Dr. barwelliand visible even in an aclitellate specimen like the one depicted in Shen and Yeo (2005)was not presented in Fig. 1Bof Chen (1938). Furthermore, the proportion of the entire sperm duct to the testis sac is almost equal in Blakemore and Kupriyanova (2010, Fig. 1.1c), while this proportion is much smaller as shown in Chen (1938, Fig. 1B). In addition, other accounts such as body size and presence or absence of dorsal pores also vary between Dr. barwelliand Dr. glabella. Beddard (1886)described Dr. barwellias a small earthworm not more than 1.5 inch(about 38 mm) in length. Body length of specimens of Dr. barwellirecorded from Taiwanis 25–44 mm(Shen 2018) and the specimen from Singaporeis 40 mmlong ( Shen and Yeo 2005). Therefore, Dr. glabellais apparently larger. Regarding the presence or absence of dorsal pores, Beddard (1886)mentioned that “The only apertures that I could detect upon the surface of the body besides the mouth and anus were two oval slit-like orifices with tumid yellowish lips, which are the male generative orifices”. This is consistent with the observation of Easton (1984)and Shen (2018) that dorsal pores are totally absent in Dr. barwelli. However, later Beddard (1888; 1891) mistook Drawida beddardii( Rosa, 1890)for Dr. barwelliand stated in Beddard (1891)that “Dorsal pores are present” (see Shen 2018). Due to misidentification by Beddard (1888; 1891; 1893; 1895), Dr. beddardiihas long been wrongly considered synonymous with Dr. barwelli(see Shen et al. 2015) which leads to the erroneous conclusion by Blakemore (2010, p. 142) that the presence or absence of dorsal pores is possibly an intermittent character. As to Dr. glabella, dorsal pores are evident behind the clitellum ( Chen 1938). Accordingly, Dr. glabellais not synonymous with Dr. barwelliand should be recognized as a valid species. Drawidacf. barwellifound in Koreawere based on two immature specimens with a body length of 45–60 mm, moderately-coiled sperm ducts and four gizzards in XV–XVIII ( Blakemore et al. 2014). Beddard (1886)did not mention the number and position of gizzards in Dr. barwelli, but Beddard (1893; 1895) mentioned three gizzards in XIII–XV in Drawida bahamensis( Beddard, 1893), a junior synonym of Dr. barwelli( Easton 1984). Easton (1984)reported three or four gizzards in XII–XVI in specimens from south-western Pacific islands and Central America while three gizzards in XIV–XVI were found in specimens from Taiwan(Shen 2018). The much larger size, not so heavily coiled sperm ducts and posteriorly placed gizzards of specimens from Koreaare morphologically dissimilar to Dr. barwelli. Moreover, the DNA barcode tree presented in Blakemore et al. (2014, Fig. 1) clearly shows that the Korean specimens should be assigned to Dr. eda(see also Fig. 3in this study). The following species of Drawidaare, like Dr. alishanensis, also small worms without papillae or genital markings: Dr. beddardii, Dr. fluviatilis Stephenson, 1924, Dr. delicata Gates, 1962and Dr. tenellula Gates, 1962from Burma, Dr. affinis Stephenson, 1917from Bengal, and Dr. ramnadana Michaelsen, 1907, Dr. willsi Michaelsen, 1907, Dr. fakir Cognetti, 1911, Dr. brunnea Stephenson, 1915, and Dr. paradoxa Rao, 1921from India. Among them, Dr. fluviatilis, Dr. delicata, Dr. tenellula, Dr. affinis, Dr. ramnadana( Michaelsen 1909), Dr. willsi( Michaelsen 1909), Dr. brunnea, and Dr. paradoxacan be separated from Dr. alishanensisby their coiled sperm ducts. Dr. beddardiihas rather short, S-shaped sperm ducts ( Rosa 1890; Gates 1972) similar to those of Dr. alishanensis, but it has higher segment numbers (145–188), large spermathecal pores and 3–4 gizzards in XII–XIX ( Gates 1972). Gates (1972, p. 246)erroneously synonymized Dr. fluviatiliswith Dr. beddardii; the sperm ducts and spermathecal pores of both species are distinctively different. Drawida fakir Cognetti, 1911from south Indiais slightly larger than Dr. alishanensiswith a body length of 85 mmand maximum diameter 3 mm. It has a segment number, 98, quite close to that of Dr. alishanensis. Both species share the following combination of characters: (1) absence of papillae or genital markings, (2) short and slightly wavy sperm ducts, (3) ovisacs in XII and (4) loosely coiled spermathecal ducts ( Cognetti 1911; Stephenson 1923). However, Dr. fakirhas four gizzards in XIII–XVI, tubular and closely coiled male atriums, and no spermathecal atrium, while Dr. alishanensishas two gizzards in XII–XIII, cotton-like and transversely elongated oval male atrium and small spermathecal atrium anterior to septum 7/8. Characters of all the above-mentioned Drawidaspecies with short sperm ducts and without genital markings are summarized in Table 1.