Andiorrhinus Cognetti, 1908

Hernández-García, Luis Manuel, Sousa, Sandriel Costa, Beckman, Ruana Aretha Farias Santiago, Pereira, Natália Jovita & Rousseau, Guillaume Xavier, 2023, Rhinodrilus priscilae and Andiorrhinus (Amazonidrilus) caxiuana (Crassiclitellata Rcrilidae) two new species from Caxiuanã National Forest, Zootaxa 5255 (1), pp. 212-219 : 215-217

Genus Andiorrhinus Cognetti, 1908

Andiorrhinus Cognetti, 1908: 919–923 ; Michaelsen 1918: 190; Cordero 1945: 2; Righi 1971: 16; 1986: 124; 1993: 125–139; Zicsi 1995: 588.

Type species. Andiorrhinus salvadori Cognetti, 1908 .

Diagnosis. Eight setae per segment; intraclitellar male pores; three pairs of calciferous glands in VII–IX, lamellar structure; a pair of testes in X and XI within testis sacs; two pairs of seminal vesicles restricted to XI and XII; ovaries in XIII; spermathecae in pre-testicular segments.

Subgenus Andiorrhinus (Amazonidrilus) Righi, 1993

Type species. Andiorrhinus (Amaz.) rondoniensis Righi, 1986

Andiorrhinus (Amazonidrilus) caxiuana n. sp. Hernandez-Garcia & Sousa ( Figure 2A,G )

Holotype. Holotype. MPEG. ANL 001208 , one adult, complete, secondary forest 1 year old, FLONA de Caxiuan „, Melgaço, Pará, Brazil, 1°46’7’’S, 51°26’35’’W, 24 masl, January 2014. Santos, P. coll.

Paratype. MPEG. ANL 001206 , two adults, one amputee and one fracgmented, secondary forest 2 years old , FLONA de Caxiuan „, Melgaço, Pará, Brazil, 1°46’7’’S, 51°26’35’’W, 24 masl, January 2014. Santos, P. coll. MPEG. ANL 001207 , one preadult mature, complete, secondary forest 2 years old, FLONA de Caxiuan„, Melgaço, Pará, Brazil, 1°46’7’’S, 51°26’35’’W, 24 masl, July 2016. Santos, P. coll. MPEG. ANL 002396 , one adult, complete, secondary forest 40 years old , FLONA de Caxiuan „, Melgaço, Pará, Brazil, 1°45’32.083”S, 51°26’22.236”W, 28 masl, January 2014. Medeiros, P.S.J. coll. MPEG. ANL 002397 , one adult, complete, secondary forest 40 years old, FLONA de Caxiuan„, Melgaço, Pará, Brazil, 1°44’36.157”S, 51°26’44.167”W, 43 masl, May 2014. Medeiros, P.S.J. coll.

Etymology. The species name derives from the region where earthworms where collected.

Description. Dimensions: holotype 113 mm in length by 4.5 mm at X, 5.1 mm at clitellum, 4.3 mm at XXX, 158 segments; paratypes 1 and 2 amputee 57—84 mm in length by 3.5–4.9 mm at X, 5.0– 5.8 mm at clitellum and 4.2–5.0 mm at XXX, 62–119 segments respectively. Paratypes 3 and 4 complete 57–84 mm in length by 3.9–4.0 mm at X, 4.0–5.0 mm at clitellum and 3.5–3.8 mm at XXX, 62–119 segments respectively. Body cylindrical, dark brown in color after fixed. Setae ab and cd commence on IV, closely paired-type. Setal arrangement aa:ab:bc:cd:dd = 7:1:15:0.8:53 at XXX for holotype. Prostomium tentacular 4.5–5.8 mm in length ( Fig 2A ). Clitellum beige in color, saddle shaped reaching just near B line, in XVI–1/2XXV ( Fig 2B ). In XVI the clitellum above only setae cd. Puberal furrows in XX-XXIII just beside B line. Post-clitellar common setae slightly sigmoidal, setae ab of XXX 430–500 μ m in length, smooth at the apical part and truncated at base ( Fig. 2C ). Genital markings as smooth white papillae are in 18–23 on AB line. Genital setae associated to follicles of spermathecae of IX on ab, straight, 1700–1850 μ m in length. Genital setae ab of XXII, straight, seta a 1930–2050 μ m in length, the concave sub-apical part ornamented with fourteen-fifteen alternate semilunar excavations, setae b 2830–3000 μ m in length, the concave sub-apical part ornamented with nineteen–twenty alternate semilunar excavations ( Fig. 2D ). Microscopical male and female pores not recognized externally. Three pairs of spermathecal pore marks are present just near the intersegmental lines 6/7–8/ 9 in CD line ( Fig. 2E ). Nephropores at anterior part of segments near the intersegmental limit, and aligned with CD line, first nephropore visible in V.

Pre-clitellar septa very fragile, membranous septa in 11/12–14/15, intraclitellar septa membranous. Gizzard in segment VI, 5.0 mm in wide and 6.2 mm in length, highly muscular, internal musculature 1.2 mm. Intestinal origin in XXVIII. Typhlosole as a folded lamina at XXIX extended to CXVIII, occupying approximately 70-80% of the intestinal diameter. Three pairs of lamellar calciferous glands in VII–IX, ventral-dorsal connection, pedunculated at dorsal connection, and with 26–28 lamella in the middle region. The glands are 0.6–1.0 mm wide and 2.5–2.7 mm in length ( Fig. 2F ). Holonephric, post-clitellar nephridium vesiculate, open to coelom, with one loop connected to the bladder compartment by a glandular tube. The bladder is extended almost a half of the circumference to the body. The vascular system with ventral trunk, single dorsal trunk, and three pairs of lateral blood vessels in VII–IX. Four pairs of big lateroesophageal hearts in X–XIII. Supra-esophageal vessel runs over the dorsal side. Those of X–XXVIII thinner than intestine region.

One pair of flabellate ovaries are in XIII. Female funnels on 13/14. Female pores open in 14/ 15 in A line. Three pairs of spermathecae in VII–IX; seminal chambers are present in the ducts, the duct of the more developed spermathecae measures 0.35 mm wide and 0.3–0.4 mm in length, the oval ampulla measures 0.6–0.75 mm wide and 0.45–0.5 mm in length ( Fig. 2G ). A ventral and big glandular mass is observed fixed to the wall of IX, near the spermatheca with follicles associated to genital setae ab, there is not replacement setae. Spermathecal pores open just near the intersegmental limits 6/7, 7/8, 8/ 9 in CD line. Two pairs of globular testes sacs are beside to hearts in X–XI. Male funnels are on anterior body wall. A pair of seminal vesicles are in XI–XII. A pair of deferent sperm ducts go parallel through B line and open on 19/20.

Remarks. 48 species distributed in Venezuela (24), Brazil (20), Colombia (3), Bolivia (3), Guyana (1), Paraguay (1). Some species found in more than one country (Brown & Fragoso 2007). Andiorrhinus with four pairs of intestinal hearts in 10, 11, 12, 13 ( Righi 1993); 21 species distributed in Brazil (14), Venezuela (5), Bolivia (3), Colombia (1), Paraguay (1). Some species found in two countries (Brown & Fragoso 2007).

The new species Andiorrhinus (Amazonidrilus) caxiuana n. sp. is similar to A. (Amaz.) rondoniensis Righi 1986 and A. (Amaz.) gavi Righi & Araujo 1999 by the clitellum and tubercula pubertatis extension in XVI–XXV and 1/2XX, XX–XXIII, 1/2XXIII. The main difference with A. (Amaz.) rondoniensis is the male pore position, which is in XXI in A. (Amaz.) rondoniensis. Position of male pore (19/20) is the same in A. (Amaz.) gavi and A. (Amaz.) caxiuana , however there are other differences among both species; ornamented common setae, and longer genital setae (1mm) in A. (Amaz.) gavi; setae arrangement 5:1:7.3:0.7:15.7 for A. (Amaz.) gavi and 7.0:1.0:15.0:0.8:53.0 for A. (Amaz.). caxiuana ; intestine origin in XXIII for A. (Amaz.) gavi vs XXVIII for A. (Amaz.) caxiuana . A. (Amaz.) caxiuana also is smaller, at least one quarter or a half in length, and has one glandular mass associated to spermathecae in IX vs two in VII and VIII of A. (Amaz.) gavi

Figures

FIGURE 2. Andiorrhinus (Amazonidrilus) caxiuana n. sp. A. Ventral view prostomium. B. Ventral view of clitellum region. C. Right common seta a of segment XXX. D. Right genital b seta of XXII. E. Lateral view of spermathecae pores. F. View in crosssection of the right calciferous gland of IX. G. Dorsal view of right spermathecae of VIII, IX. bv: blood vessel. CG: calciferous gland. f: follicle. gm: glandular mass. np: nephropore. sch: seminal chambers of spermathecae. spe: spermathecal ampulla. spo: spermathecal pore. tp: tubercula pubertatis furrows.