Amynthas pingi ( Stephenson, 1925 )

Blakemore, Robert J., 2013, Megascolex (Perichaeta) diffringens Baird, 1869 and Pheretima pingi Stephenson, 1925 types compared to the Amynthas corticis (Kinberg, 1867) and A. carnosus (Goto & Hatai, 1899) species-groups (Oligochaeta: Megadrilacea: Megascolecidae), Journal of Species Research 2 (2), pp. 99-126 : 112-115

Amynthas pingi ( Stephenson, 1925) [= A. carnosus ]

( Fig. 11 )

Pheretima pingi Stephenson, 1925: 891 , text fig. 1 (of testis sac), plate II fig. 7 (of a likely parasitised spermatheca). [Type locality Nanking, China. Syntype in London, BMNH 1924:11:29:5]; Chen, 1933: 228, fig. 15; (non Gates, 1935: 14); 1936: 298 (syn. fornicata ); Gates, 1939: 465 (syn. kyamikia);? Ishizuka, 2001: 82, fig. 46 (mislabeled “ Pheretima pingi Chen, 1936 ”) - exactly the same as P. carnosa in fig. 9 of Chen (1959) so probably is the same.

?[ P. hongkongensis Michaelsen, 1910: 107 . Type locality Hongkong, type in Hamburg , V9084 (inspected by Gates, 1939: 446)].

?[ Pheretima fornicata Gates, 1935: 9 . [From “Tatsienlu, Szechwan” now called Kangding or Dardo (from the Tibetan name Darzedo) in the Garze Tibetan Autonomous Prefecture in western Sichuan. Types in US Natl. Mus. no. 20099]; Chen, 1936: 296 (examined type); Gates, 1939: 434. [It lacks genital markings but is otherwise stated to be similar to P. hongkongensis that has only a pair of small marking immediately median to male pores on 18 - see fornicata description below].

Amynthas pingi : Sims & Easton, 1972: 235 ( diffringens - group); Blakemore, 2012d; 2013a; 2013b.

Material examined. London type a single previously dissected mature specimen, labeled: “ Pheretima pingi 1924.11.29.5 HOLOTYPE (sic) Nanking, China Don. Prof C. Ping ”; the sample jar contained a smaller vial containing a spermatheca (8rhs) with a note “Spermatheca from new Chinese worm (Prof. Ping)” in Stephenson’s hand .

Diagnosis. Amynthas with spermathecal pores in 5/6/7/ 8/9 [as in A. corticis and A. carnosus cf A. pingi chungkingensis ( Chen, 1936) with spermathecal pores in 6/7/8/9 now separated at species level]. Genital markings paired ventrally on 8, 9 and 18 (sometimes in 19 too) (as also in A. carnosus ). Intestinal caeca simple from 27 (as in A. carnosus cf A. divergens ).

Distribution. Nanking, plus one (dubious?) specimen from Kuatun, Fukien at 3000-5000ft ( Gates, 1943) and another dubious report from Japan (see Blakemore, 2003). Abundant in Nanking constituting ~30% of worms there [ Stephenson (1931: 56) on information from Dr Chen] where it was found with Metaphire houlleti . Occurrence elsewhere now suspect.

Lengths: Type 132 mm [for pingi Gates gave range as “ 140-340 mm ” which was to the higher end and should perhaps be revised for carnosus to 130-340 mm or, when A. fornicatus was included (see below) to 78-340 mm]. Width: ca. 4-9 mm. Segments: 126 or 127 in type. Colour: Dark slate dorsally, paler ventrally; clitellum darker; type bleached to a uniform buff in preservative (alcohol?). Prostomium: Broad closed epilobous. First dorsal pore: 11/12 or 12/13 (indeterminate in type as previously dissected, presumably by Stephenson, thus Gates could not be as categorical and gave range of 11/ 12-13/14). Setae: Usually 35-60 per segment (eg in the type I counted 36 on segment 5 and 60 on segment 12), those of segments 2-9 fewer but enlarged. Cf Gates (1939: 466) who had 17-66, but appears not to have included the count from the types. Clitellum: Annular 14-16, no setae visible. Male pores: On 18 on elliptical porophore. Female pores: Single on 14. Spermathecal pores: 5/6/7/8/9 ca, 0.3 circumference apart at posterior of translucent areas in 5-8. Cf. Gates (1939) pre-intersegmental in 5-8, this erroneous. Genital markings: Paired discs just median to lines of male and spermathecal pores (or sometimes shifted more ventrally) presetal on 8, 9 (and sometimes on 18 and 19 too?); typically with a presetal pair in 8 & 9 and a postsetal pair on 18.

Septa: 5/6-7/8 strong, 8/9 lacking (in type or membranous in other specimens), 9/10 thin (or also lacking in other specimens), 10/11 and 11/12 considerable, 12/13 and thereafter thinning. Lymph glands dorsally on intersegments, large, paired from 15 in type (pers. obs.) or said to be from 19 by other workers. Dorsal blood vessel (dbv): Single. Hearts: 9,10-13; Gates (1939) says hearts in 10 are present except in type, this possibly wrong as from my inspection there were thin commissurals paired anteriorly in 10 just behind septum 9/10 and connecting directly to dorsal blood vessel (dbv), rather than posteriorly and connecting to dbv via thin constrictions that traverse posterior septa in 11-13. Gizzard: Single in 8-9. Calciferous glands: Absent; but oesophagus dilated and vascularized in type in 12 and 13 (pers. obs.). Intestine origin (caeca, typhlosole): In 15 and/or 16 (in type in 15 lhs and 16rhs) sometimes given as from 19 by other workers; caeca simple smooth from 27; thin lamellar typhlosole present from after 27 (type pers. obs.). Nephridia: Meroic. Male organs: Testes/funnels in 10 and 11 in sacs; seminal vesicles large in 11 and 12; pseudovesicles paired in 13 in type (pers. obs.). Ovaries: In 13 as usual; ovisacs small in 14 in type (pers. obs.). Prostates: Racemose glands in 17-19, duct muscular. Spermathecae: Four pairs, the ampulla oval, duct almost as long; the diverticulum from near body wall reached to half the height of ampulla with slender stalk and wider seminal chamber. Several tubercules were described on spermathecal duct walls by Stephenson, and each spermatheca in the type has these, which are probably parasitic artefacts (as also suggested by Gates, 1939: 468). Gut contents: Silty soil and coarse leafy organic remains (type, pers. obs.).

Remarks. Mistakes in Gates’ (1939) redefinition of Pheretima pingi are that the setal counts are much lower than occur in the actual type (see note below on Gates’ mistakes); he also mistook the septa and hearts and, quite importantly, provided genital markings that comply with A. carnosus and had spermathecal pores that he insisted were posterior in segments 5-8 but that are now shown to be in the intersegmental furrows of 5/6/7/8/ 9 in the types of both A. pingi and A. carnosus .

The ‘characteristic’ tubercules on the spermathecal ducts are not nephridial and probably are due merely to Monocystis infestation as was also suggested by Gates (1939: 468), thus removing any justification for retaining pingi separately from A. carnosus ( Goto & Hatai, 1899) . Thus its abundance in Nanking may be indicative of a possible endemic range for A. carnosus , as was suggested by Chen (1936: 275) and as concluded by Kobayashi (1936) from Korean work. Slight reticence on merging these taxa by Blakemore (2012a; 2013b) was due to supposed larger size in A. pingi - now known to be false as the type is only 132 mm long - and a later onset of intestine origin and septal glands, now also proven false. It is possible, nevertheless, that Amynthas chungkingensis with spermathecae in 6/7/8/9 (as found in two of Kobayashi’s 204 Korean specimens) be retained as a separate species, this dependent on access and inspection of its types now that A. pingi is resolved. Gates (1939: 469) compared his concept of A. pingi to Pheretima diffringens (cf. A. corticis proper) and differentiated it on these points:

� Larger setal numbers (but he undercounted those in his concept of A. pingi ).

� Posterior location of first dorsal pore (now known to be irrelevant and overlapping).

� Segmental location of spermathecal pores (now known to be mistaken).

� Post-clitellar GMs (irrelevant when lack of markings permissible).

� Presence of complete septum 8/9 (variable and also mistaken by Gates in the type).

Gates (1939: 436) further claimed that his P. fornicata Gates, 1925 from Tatsienlu, Tibet was distinguished from P. hongkongensis Michaelsen, 1910 , by the dorsal gap in the setal circle of segment 2 (hardly significant), the absence of genital markings (ditto), and the exclusion of the anterior seminal vesicles from the testis sac of segment 11 (ditto). Thus P. fornicata possibly qualifies for synonymy of P. hongkongensis but the question remains: how separate are these two taxa from A. pingi ? The former, P. fornicata , complies with A. pingi except for its lack of genital markings, i.e. it is within the ambit of Kobayashi’s (1936) definition of A. carnosus . The latter, P. hongkongensis , also redescribed by Gates (1939: 446) from its type, differs mostly on its making near the male pores which is similar to but not explicit in Kobayashi’s description of A. carnosus . This issue is discussed further in the next section on ‘ Pheretima fornicata ’.

The current lectotype of P. pingi (= A. carnosus ) then, agrees morphologically with two Hikone, Shiga specimens from Japan that provided DNA samples (JET112-114|An- 460-461). The DNA of these Shiga specimens agrees (100%) with that of Korean specimens from Jeju and the Korean mainland that provided DNA samples WO34, WO67, WO32, WO24, w57 ( Blakemore, 2013a) and slightly less so (>99%) for w37 and w55 samples, respectively, from Geoman and Incheon specimens. These specimens differ inconsequentially from the description given above of ‘ P. pingi ’ further solidifying the definition of A. carnosus proper that now surely includes pingi as a junior synonym.

DNA was not extractable from types of either A. carnosus nor of A. pingi . However, megaBLAST of both A. carnosus from Hikone (Tokyo An-460 DNA JET-112) and A. carnosus from Geoman (NIBR IV261234 DNA w37) comply 99% with A. carnosus non-type specimens from Japan (eg GenBank AB542452) and, moreover, both sequences also agree 99% (656/658) with each other by BLASTn. Since the Hikone specimen resembles (and was first though to be) A. pingi , and the Geoman specimen is the same morphologically as the A. carnosus neotype, thus both specimens provide a de facto link uniting the neotype of A. carnosus with the lectotype of A. pingi to support their merger.

Two anomalous specimens were described as “? Amynthas pingi ” from Ulleungdo ( Blakemore, 2013a: 60) and as “ A. carnosus ” from Incheon that provided DNA samples w54 and w56, respectively. While the Incheon specimen (along with a paratype from Busan) was named as Amynthas carnosus roki Blakemore, 2013 in a complementary paper in the current issue; the Ulleungdo specimen also deserving sub-specific status and is nominated above as A. carnosus naribunji .

As part of this revision of A. carnosus , it may be noted its erstwhile synonym, A. fornicatus is sometimes maintained by some Chinese workers (eg Shen et al., 2003; Wang & Qiu, 2005; Sun et al., 2012) and it is now beholden on them to similarly clarify and define their taxonomic concepts. Nevertheless, I here briefly consider this taxon for clarity.

Figures

Fig. 11. Pheretima pingi previously dissected syntype (London BMNH 1924.11.29.5) showing habitus, prostomium plus spermathecae, caecum and 18lhs prostate in situ with enlargements of spermathecal pores and 18rhs male pore; a spermatheca with parasitic artefacts from 8rhs (removed by Stephenson and placed into a vial) figured separately at two scales and two aspects; [boxed is copy of Stephenson’s sketch of same spermatheca (cf more detail in Chen, 1933: fig. 15)]. Compare to Fig. 3.