Guestphalinus Michaelsen, 1933

Fend, Steven V., Rodriguez, Pilar, Achurra, Ainara & Erséus, Christer, 2017, On Kincaidiana Altman, 1936 and Guestphalinus Michaelsen, 1933 (Annelida, Clitellata, Lumbriculidae), with the descriptions of three new species, European Journal of Taxonomy 361, pp. 1-46 : 19

Guestphalinus Michaelsen, 1933

Type species

Dorydrilus (Guestphalinus) wiardi Michaelsen, 1933 .

Included species

Guestphalinus wiardi ( Michaelsen, 1933)

Guestphalinus exilis Fend & Rodriguez sp. nov.

Guestphalinus elephantinus Fend & Rodriguez sp. nov.

Emended diagnosis (modified from Michaelsen 1933; Cook 1971)

Medium-sized to large worms with a filiform proboscis. Chaetae two per bundle. Paired testes in VIII and IX, one pair of ovaries in X. Male pores paired in IX, near 9/10. Spermathecal pores paired in IX, anterior to the male pores. Petiolate copulatory glands (= Pubertätsdrüsen in Michaelsen 1933) associated with male and/or spermathecal pores. Male duct semiprosoporous. Penes absent. Atria elongate, cylindrical to club-shaped, ental part loosely covered with multicellular, pyriform prostate glands. Anterior vasa deferentia form a loop in the pre-atrial segment before entering the atrial segment. Paired spermathecae in the atrial segment, anterior to the atria.

Distribution

Europe and northwestern USA (present study). Guestphalinus wiardi is rarely reported, but is known from subterranean or spring habitats in Germany ( Michaelsen 1933; Griepenburg 1941), Slovenia ( Hrabě 1973) and Italy (new material used for the present description, see below), with other records from mountain streams in Crimea ( Dembitsky 1987).

Remarks

Among the lumbriculids with a filiform proboscis, Guestphalinus is distinguished from the semiprosoporous species of Rhynchelmis , Eclipidrilus (Premnodrilus) Smith, 1900 and Eremidrilus Fend & Rodriguez, 2003 by the location of the male pores in IX (instead of X), the spermathecae in the atrial segment, the anterior vasa deferentia entering the pre-atrial segment, and the morphology of the elongate spermathecae. In addition to being prosoporous, the two Kincaidiana species are easily distinguished from Guestphalinus by the presence of spermathecae also in the first two postatrial segments, and by a different type of modified chaetae in several pre-clitellar segments. Uktena is distinguished from other proboscis-bearing lumbriculids by having atria and spermathecae in VIII (rather than IX), in addition to characters unique within the family: spermatophores, a spermathecal copulatory organ, and multiple genital chaetae ( Fend et al. 2015).

Guestphalinus was originally described as a subgenus of Dorydrilus Piguet, 1913 ( Michaelsen 1933) , but was later elevated to generic status ( Hrabě 1936, although spelled Questphalinus in that paper). This decision, although considered provisional in the 1936 paper, has been maintained in subsequent literature ( Cook 1971; Hrabě 1973; Dembitsky 1987).