Achaeta antefolliculata, Dózsa-Farkas & Boros, 2005

Dózsa-Farkas, K. & Boros, G., 2005, Achaeta Antefolliculata Sp. N., A New Enchytraeid Species (Oligochaeta, Enchytraeidae) From The Rock Grassland Of The Sas-Hegy In Hungary, Acta Zoologica Academiae Scientiarum Hungaricae 51 (4), pp. 279-285 : 280-285

publication ID	https://doi.org/ 10.5281/zenodo.12586247
persistent identifier	https://treatment.plazi.org/id/58193623-2B0C-FFE0-504B-F9AA3F22FC42
treatment provided by	Felipe
scientific name	Achaeta antefolliculata
status	sp. nov.

Treatment

Achaeta antefolliculata sp. n.

( Figs 1–13 View Figs 1–6 View Figs 7–9 View Figs 10–13 )

Holotype: A 4 (1939) stained whole mount.

Type locality: Hungary, Sas-hegy , open rock grassland (biotope 2), 09.01.2005 .

Paratypes: P. 79.1 (1941) – P.79.2 (1941) seven specimens, whole mounted on two slides, biotope 2, 23.04.2004 , P.79.3 (1942) – P.79.13 (1952) fourteen specimens, whole mounted on 11 slides, biotope 2, 09.01.2005 , P.79.14 (1953) two specimens, whole mounted on one slide, biotope 2, 28.10.2004 , P.79.15- P.79.20 56 adult + 5 juvenile specimens in 70% ethanol : P.79.15 (1954) 35 specimens, biotopes 2 and 3, 23.04.2004 , P. 79.16 (1955) one specimen, biotope 1, 23.04.2004 , P.79.17 (1956) two specimens, biotope 4, 28.04.2004 , P.79.18 (1957) six specimens, biotope 2, 28.04.2004 , P.79.19 (1958) seven adult and 5 juvenile specimens, biotope 3, 28.04.2004 , P.79.20 (1959) five specimens, biotope 3, 09.01.2005 .

Type locality of paratypes: Hungary, Sas-hegy , open rock grassland (biotope 2), closed rock grassland (biotope 1), scrubbery (biotope 3) and moderately disturbed Festuco pallenti-Brometum pannonici (biotope 4) .

Etymology: Named for the epidermal follicles, which are present only in the anterior segments from the head to segment VI.

Description – Very small species, 2.4–2.8 (3.5) mm long with a diameter of 0.14–0.19 mm at VIII, 0.16–0.22 mm at XII, 20–21 segments, whitish colour. Holotype (fix): 2.7 mm long, diameter 0.19 mm at VIII and 0.22 at clitellum, segments: 20. Bottle-shaped cells (setal follicles) absent, but on the dorso-lateral surface of the segment I and segments III, IV, V and VI there are one pair of oval epidermal follicles, which are fixed in the body wall (slightly protruding into the body cavity and unlike in many Achaeta species possessing bottle-shaped cells, they do not bend when the animal is moving) ( Figs 1f View Figs 1–6 , 7, 8 View Figs 7–9 ). The length: width ratio of follicles is about 22–30: 12–30 µm. The epidermal follicles stain well in borax-carmine and contain cells inside. In some of the follicles this mass of cells is concentrated in the inner part of the follicle, facing the body cavity. The organ as a whole, seems to be a gland, however, an orifice has not been observed either in live, or in stained specimens. To reveal the structure and possible function of the organ, histological sectioning is indispensable. One pair of lens-shaped, hyaline epithelial cells are present dorsally, in the same transversal section where the epidermal follicles are positioned but the lens-shaped cells are not always conspicuous. Clitellum extends over XII–1/2 XIII, it is covered by 20 regular, transverse rows of gland cells. The hyaline cells are arranged in four more or less regular longitudinal fields dorso-laterally, usually with longitudinally oriented irregular rows of small granular cells in between ( Fig. 13 View Figs 10–13 ). Clitellum is broken in a thin line dorsally between the hyaline fields. Ventro-laterally only granulated gland cells are present in rows ( Fig. 11 View Figs 10–13 ). Gland cells are absent between the two penial bulbs. The hyaline glands field is not always conspicuous because the hyaline cells are probably only enlargened and look characteristic during the reproducting stage ( Fig. 13 View Figs 10–13 ). Often, even with egg-bearing animals, granulated cells dominate. The brain is about twice as long as wide (length 87–95 µm), its posterior end is slightly concave ( Figs 1b View Figs 1–6 & 8b View Figs 7–9 ). Head pore small, nearly on tip of 0. Dorsolateral oesophageal appendages in V poorly developed ( Fig. 1a View Figs 1–6 ). First and second pairs of pharyngeal glands (septal glands) broadly united dorsally, the third pair has a narrow connection, all with ventral lobes ( Figs 1 View Figs 1–6 , 9 View Figs 7–9 pg, 7). One pair of secondary pharyngeal glands in V ( Figs 1 View Figs 1–6 & 9 View Figs 7–9 spg). The oesophagus joins the intestine with a sharp bend in VII ( Fig. 1 View Figs 1–6 oe). Chloragogen cells start from V, a dense layer from VII onwards containing brown-yellow globules; the length of cells is 20–25 µm ( Fig. 1c View Figs 1–6 ). The septa of IV/V and V/VI are thickened. The dorsal vessel originates in VII with pulsating expansion in VII and VI ( Fig. 1 View Figs 1–6 dv). Blood is colourless. Coelomocytes 30–50 µm (viv) and 18–30 µm (fix) long, oval with sharp ends and hairs on the tips, they have a hyaline border and irregular inner structures ( Fig. 4 View Figs 1–6 ). Nephridia of the usual type of the genus ( Figs 1n & 6 View Figs 1–6 ) two pairs in front of the clitellum at VI/VII, VII/VIII. Postclitellar, mostly 3–4 pairs in the last segments. Seminal vesicle absent. Sperm funnel ×1.5–2 as long as wide (about 43–55 µm long (viv)) and about 1/4–1/3 as long as body diameter, collar distinct, narrower than the funnel body ( Figs 5 View Figs 1–6 & 12 View Figs 10–13 ). The sperm duct is 5 µm, thick and short, about ×4–5 as long as the length of the funnel. Spermatozoa ca. 40–45 µm long and heads ca. 15 µm (viv). The small sperm funnel, 6 = nephridium mary pharyngeal glands, spg = secondary pharyngeal glands funnel (marked with arrow), 13 = hyaline gland cells with some granular cells in dorsal view male copulatory organ (16–23 µm diameter, fix) in XII surrounded by some indistinct glands ( Figs 10 & 11 View Figs 10–13 ). Distance between male pores: 55–60 µm (fix). Spermathecae free, restricted to V. No glands at the spermathecal pores. Ampullae spherical with some sperm in it. Spermathecal ducts about twice as long as the ampullae ( Figs 1s, 3 View Figs 1–6 & 9 View Figs 7–9 ).

Remarks. Achaeta antefolliculata is similar to the Achaeta group devoid of bottle-shaped cells (setal follicles) and with the spermathecae restricted to V, but it is clearly distinguished from the other members of the group by the 5 pairs of dorsolateral epidermal follicles (with a different shape from the usual “setal follicles”) present in the first six segments only and differs from them by the presence of one pair of secondary pharyngeal glands in V.

Acknowledgements – This research was financed partly by the Hungarian Scientific Research Fund (OTKA 034864). Some research equipments (microscope and digital camera) were also provided by the OTKA (M27225 and M045482).