Leptotyphlops longicaudus, Hahn, 1980

Published, First, 2007, A revision of the genus Leptotyphlops in northeastern Africa and southwestern Arabia (Serpentes: Leptotyphlopidae), Zootaxa 1408, pp. 1-78 : 51-56

Leptotyphlops longicaudus species group

Leptotyphlops braccianii ( mean based two males, BMNH 1905.11 .7.41, MCZ 40089, and two females, MCZ 52190, 53330 )

Posterior tip of sternohyoideus 13.5%, sternohyoideus-heart gap 0.09, heart 4.2% (MP = 16.7%), snoutheart interval 18.8%, heart-liver gap 8.1%, liver lobes multipartite, right liver 42.8% (MP = 48.3%) with 47.3 (34–57) segments, left liver 38.0% (MP = 47.9%) with 41.3 (35–47) segments, a zig-zag postcaval vein, anterior liver extension 0.06, posterior liver tail 0.07, left liver = 0.88 right liver, liver-gall bladder gap 0.6%, gall bladder 1.5% (MP = 70.9%) adjacent to pancreas (1.8%) and caudal to juxtasplenic body (1.8%), testes multipartite, right testis 3.7% (MP = 82.9%) with 11.5 (11–12) segments, left testis 4.2% (MP = 85.7%) with 11.0 (9–13) segments, right ovary 3.7% (MP = 75.6%) with no ova and 14 follicles, left ovary 5.3% (MP = 79.8%) with 1.5 (0–3) ova and 9.0 (6–12) follicles, right adrenal MP = 83.4%, left adrenal MP = 85.1%, kidneys completely segmented, right kidney 3.4% (MP = 86.7%) with 5.8 (4–9) segments, left kidney 3.7% (MP = 89.6%) with 5.5 (4–8) segments, kidney overalp 0.13, kidney-vent interval 15.0%, kidney-vent gap 8.6%, rectal caecum 1.5%, 1–2 times the diameter of adjacent small intestine, caecum-vent interval 7.0%.

Left lung complex and tracheal lung lacking, trachea 17.8% (MP = 10.0%) with an estimated 153.8 (140– 162) tracheal rings or 85.8 rings/10% SVL, anterior tip of lung 16.8%, cardiac lung 2.0%, tracheal entry terminal, right lung 35.7% (MP = 36.7%) with one layer of large circular or oval faveoli cranially, caudal portion of lung with trabecular parenchyma forming reticulate pattern, posterior lung tip 54.6%, bronchus 17.7%, posterior tip of bronchus 36.5%, bronchus = 0.53 right lung, trachea-bronchus 35.4% (MP = 18.8%), total lung 37.7% (MP = 35.7%).

Reproduction probably in fall as MCZ 52190 (SVL 109 mm, MBD 1.5 mm) with no ova on 2 March 1951 but MCZ 53330 (SVL 119 mm, MBD = 1.8 mm) with 3 vitellogenic ova (2 x 1 mm) in left ovary (right ovary missing) on 4–13 July 1950.

Leptotyphlops burii ( mean based on two females, BMNH 1937.11 .1.10, MZUF 4472 )

Posterior tip of sternohyoideus 8.1%, sternohyoideus-heart gap 0.40, heart 4.3% (MP = 16.0%), snout-heart interval 18.1%, heart-liver gap 6.6%, liver lobes multipartite, right liver 37.0% (MP = 43.2%) with 55.5 (53– 58) segments, left liver 31.1% (MP = 43.2%) with 51.5 (49–54) segments, anterior liver extension 0.08, posterior liver tail 0.08, left liver = 0.84 right liver, liver-gall bladder gap 0.8%, gall bladder 1.2% (MP = 63.0%) wedged between caudal pancreas (1.2%) and craniad spleen and juxtasplenic body (1.6%), right ovary 3.5% (MP = 77.6%) with 1.5 (1–2) ova and 9.5 (7–12) follicles, left ovary 2.3% (MP = 79.0%), with 2.0 (2–2) ova and 6.0 (5–7) follicles, right adrenal MP = 81.0%, left adrenal MP = 82.2%, kidneys multipartite, with appearance of a string of oval spheroids, right kidney 3.3% (MP = 83.7%) with 6.5 (6–7) segments, left kidney 3.5% (MP = 86.7%) with 7.0 (7–7) segments, kidney overlap 0.05, kidney-vent interval 18.0%, kidney-vent gap 11.6%, rectal caecum 1.4%, 2–3 times the diameter of adjacent small intestine, caecum-vent interval 10.9%.

Respiratory system lacking tracheal lung and left lung complex, trachea 17.3% (MP = 9.4%), estimated number of tracheal rings 214.5 (209–220) or 123.4 rings/10% SVL, anterior tip of lung 16.1%, cardiac lung 2.0%, tracheal entry terminal, right lung 24.8% (MP = 30.5%), cranial 4/10 with two tiers of diamond-shaped faveoli with knobs of smooth muscle at faveolar junctions, mesial 1/4 with ediculae, caudal 1/3 reticulate with trabeculae, posterior lung tip 42.8%, bronchus 15.9%, posterior tip of bronchus 33.9%, bronchus = 0.64 right lung, trachea-bronchus 33.1% (MP = 17.4%), total lung 26.7 (MP = 29.5%).

Reproduction. BMNH 1937.11.1.10 (SVL 167 mm, MBD 2.6 mm) with 2/1 vitellogenic ova and 7/12 follicles in September, 1936.

Leptotyphlops cairi ( mean based on three males, CAS 18144, FMNH 64030 , USNM 130459 , and four females, CAS 18148, FMNH 64038 , 129894 , NMZB 15419 )

Posterior tip of sternohyoideus 9.3%, sternohyoideus-heart gap 0.21, heart 3.5% (MP = 13.5%), snout-heart interval 15.3%, heart-liver gap 8.0%, liver lobes multipartite, right liver 38.2% (MP = 42.4%), with 50.0 (40– 59) segments, left liver 32.3% (MP = 39.4%) with 42.6 (38–50) segments, postcava straight, no anterior liver extension (tips symmetrical), posterior liver tail 0.16, left liver = 0.83 right liver, liver-gall bladder gap 1.6%, gall bladder 1.1% (MP = 63.6%) wedged between caudal pancreas (1.7%) and cranial spleen (0.7%) with juxtasplenic body (1.8%), pancreas with thin splenic limb, testes multipartite, right testis 5.7% (MP = 79.2%) with 12.0 (11–13) segments, left testis 5.6% (MP = 83.9%) with 13.0 (10–16) segments, right ovary 4.5% (MP = 79.3%) with 2.3 (1–5) ova and 14.7 (10–22) follicles, left ovary 3.9% (MP = 80.4%) with 2.3 (1–5) ova and 12.7 (5–21) follicles, right adrenal MP = 83.7%, left adrenal MP = 85.1%, kidneys compact but segmented, right kidney 4.0% (MP = 87.6%) with 6.0 (4–8) segments, left kidney 3.6% (MP = 90.2%) with 6.7 (5–9) segments, kidney-vent interval 14.4%, kidney-vent gap 8.0%, kidney overlap 0.23, rectal caecum 1.5%, 2.5–3.5 times the diameter of adjacent small intestine, caecum-vent interval 8.0%.

Respiratory system lacking tracheal lung and left lung complex, trachea 14.5% (MP = 8.0%) with an estimated 151.5 (119–196) tracheal rings or 103.7 rings/10% SVL, anterior tip of lung 13.2%, cardiac lung 2.1%, tracheal entry terminal, right lung 21.9% (MP = 26.2%), cranial 1/3–1/2 thick-walled with 3 layers of diamond-shaped faveolar parenchyma, caudal 1/2–2/3 tapered and reticulate with trabecular parenchyma, posterior tip of lung 37.1%, bronchus 15.0%, posterior tip of bronchus 30.2%, bronchus = 0.71 right lung, tracheabronchus 29.5% (MP = 15.5%), total lung 24.0% (MP = 25.2%).

Reproduction. Wallach (1998b) estimated the clutch size as 2–10. NMZB 15419 (SVL 182 mm, MBD 2.75 mm) with 5/5 vitellogenic ova (1.5–1.25 x 0.75 mm) in April, 1953; CAS 18148 (SVL 200 mm, MBD 2.5 mm) with 1/1 vitellogenic ova (1 x 0.5 mm /1.5 x 0.75 mm) and 5/10 follicles in April, 1955; FMNH 64038 (SVL 204 mm, MBD 2.5 mm) with 1/1 vitellogenic ova (1 x 0.5 mm) on 4 December 1950.

Everted hemipenis of CAS 18144 and 18145: 3.5 subcaudals in length, nude, lacking ornamentation with enlarged bulbous base and filiform distal portion with slight taper towards apex, sulcus simple.

Leptotyphlops erythraeus ( based on one male, MZUF 30109 )

Posterior tip of sternohyoideus 13.7%, sternohyoideus-heart gap 0.05, heart 4.3% (MP = 16.7%), snout-heart interval 18.8%, heart-liver gap 8.6%, liver lobes multipartite, right liver 31.0% (MP = 42.9%) with 59 segments, left liver 21.6% (MP = 43.3%) with 42 segments, anterior liver extension 0.16, posterior liver tail 0.14, left liver = 0.70 right liver, liver-gall bladder gap 2.7%, gall bladder 1.6% (MP = 62.0%), adjacent to slightly larger pancreas (2.0%) and juxtasplenic body (2.0%), testes multipartite, right testis 5.5% (MP = 77.3%) with 11 segments, left testis 4.7% (MP = 83.1%) with 13 segments, right adrenal MP = 80.4%, left adrenal MP = 85.1%, kidneys smooth, segmented and compact, right kidney 4.3% (MP = 85.7%) with 6 segments, left kidney 3.5% (MP = 89.2%) with 5 segments, kidney-vent interval 16.5%, kidney-vent gap 9.0%, kidney overlap 0.05, rectal caecum 1.6%, 3 times the diameter of adjacent small intestine, caecum-vent interval 9.8%.

Respiratory system lacking tracheal lung and left lung complex, trachea 18.0% (MP = 9.8%), estimated number of tracheal rings 160 or 85.0 rings/10% SVL, anterior lung tip 16.5%, cardiac lung 2.4%, tracheal entry terminal, right lung 22.4% (MP = 30.0%), cranial 1/5 with 2 layers of faveoli, middle 1/2 with single tier of ediculae, and caudal 1/3 reticulate with network of trabeculae, posterior tip 41.2%, bronchus 14.1%, posterior tip of bronchus 32.9%, bronchus = 0.63 right lung, trachea-bronchus 32.2% (MP = 16.9%), total lung 24.7% (MP = 28.8%).

Leptotyphlops ionidesi ( mean based on male holotype, MCZ 50069, male paratype, MCZ 18179, and three female paratypes, MCZ 18181, 57440 , 59175 )

Sternohyoideus posterior tip 13.9%, sternohyoideus-heart gap 0.07, heart 4.3% (MP = 17.1%), snout-heart interval 19.3%, heart-liver gap 6.6%, liver lobes multipartite, right liver 39.4% (MP = 45.6%) with 37.8 (35– 45) segments, left liver 27.9% (MP = 44.4%) with 35.2 (32–39) segments, anterior liver extension 0.11, posterior liver tail 0.18, left liver = 0.71 right liver, liver-gall bladder gap 2.3, gall bladder 1.4% (MP = 68.2%) adjacent to pancreas (1.4%) and caudad of large juxtasplenic body (2.2%) and spleen (1.1%), the latter with a connecting limb from pancreas, testes multipartite, right testis 4.6% (MP = 78.9%) with 7 segments, left testis 5.6% (MP = 83.0%) with 9 segments, right ovary 3.7% (MP = 82.9%) with 1.5 (1–2) vitellogenic ova and 6.7 (5–8) follicles, left ovary 2.8% (MP = 85.6%) with 1.0 (0–2) ova and 3.3 (0–5) follicles, right adrenal MP = 85.1%, left adrenal MP = 87.5%, kidneys multipartite, right kidney 3.5% (MP = 90.3%), with 6.8 (6–8) segments, left kidney 3.7% (MP = 92.6%), with 6.3 (6–7) segments, kidney overlap 0.23, kidney-vent interval 11.5%, kidney-vent gap 5.6%, rectal caecum 1.1%, equal in diameter to that of adjacent small intestine, caecum-vent interval 8.6%.

Tracheal lung and left lung complex absent, trachea 18.3% (MP = 10.1%), estimated number of tracheal rings 148.0 (126–156) or 80.6 rings/10% SVL, anterior tip of lung 17.3%, cardiac lung 2.0%, tracheal entry terminal, right lung narrow, 24.5% (MP = 31.5%) with one layer of faveoli anteriorly, posterior lung narrowly constricted and reticulate, posterior tip of right lung 43.7%, bronchus 15.8%, bronchus posterior tip 35.1%, bronchus = 0.66 right lung, trachea-bronchus 18.0% (MP = 43.7%), total lung 26.5% (MP = 30.5%).

Reproduction: MCZ 57440 (SVL 130 mm, MBD 2.4 mm) with 2/1 enlarged vitellogenic ova (2.5 x 1, 2 x 0.75 mm / 2 x 1 mm) and 0/5 follicles on 27 April 1958; MCZ 59175 lacking vitellogenic ova but with 5/8 follicles on 3 June 1958; MCZ 18181 (SVL 109 mm, MBD 2 mm) with 0/2 enlarged ova (2 x 1 mm) and 5/7 follicles on 1 August 1918. Based on these data, eggs are laid in May and a bianual cycle may be present with a second clutch in the fall.

Leptotyphlops longicaudus ( mean based on three males, CAS 85839, MCZ 51038, TM 62060 , and three females, NMZB 1400 , 2967 , TM 57956 )

Posterior tip of sternohyoideus 13.9%, sternohyoideus-heart gap 0.10, heart 3.9% (MP = 17.4%), snout-heart interval 19.3%, heart-liver gap 6.5%, liver lobes multipartite with rectangular segments, right liver 35.6% (MP = 43.6%) with 41.3 (32–48) segments, left liver 30.2% (MP = 41.4%) with 35.2 (28–41) segments, postcava straight along cranial liver and zig-zag along caudal liver, anterior liver extension variable, on right lobe (3), left lobe (2), or symmetrical (1), posterior liver tail 0.14, left liver = 0.84 right liver, no liver-gall bladder gap, gall bladder 1.2% (MP = 62.0%), wedged between caudal pancreas and craniad juxtasplenic body, all of equal size, with smaller spleen adjacent to juxtasplenic body, testes multipartite, right testis 7.8% (MP = 70.1%) with 9.5 (9–10) segments, left testis 4.9% (MP = 75.3%) with 11.0 (8–14) segments, right ovary 4.9% (MP = 78.8%) with 2.0 (0–4) ova and 10.5 (6–15) follicles, left ovary 3.2% (MP = 82.8%) with 0.7 (0–2) ova and 6.0 (4–8) follicles, right adrenal MP = 78.3%, left adrenal MP = 80.3%, kidneys smooth, segmented and compact, right kidney 3.9% (MP = 81.6%) with 6 segments, left kidney 4.3% (MP = 85.7%) with 6 segments, kidney-vent interval 20.4%, kidney-vent gap 12.2%, kidney overlap 0.01, rectal caecum 2.3%, 2–3 times the diameter of adjacent small intestine, caecum-vent interval 12.3%.

Respiratory system lacking tracheal lung and left lung complex, trachea 18.2% (MP = 10.2%), estimated number of tracheal rings 190.0 (160–272) or 103.1 rings/10% SVL, anterior lung tip 17.6%, cardiac lung 1.8%, tracheal entry terminal, right lung 30.3% (MP =34.5%), cranial half with 1–2 layers of large diamondshaped faveoli, caudal half reticulate with network of trabeculae, posterior tip 49.6%, bronchus 17.1%, posterior tip of bronchus 36.4%, bronchus = 0.58 right lung, trachea-bronchus 35.2% (MP = 18.8%), total lung 32.1% (MP = 33.6%).

Reproduction. Broadley (1959) reported 2 elongate eggs (21 x 4 mm) from a 178 mm SVL female (NMSR 1400) on 22 November 1957. Wallach (1998b) estimated the clutch size as 2–6. NMZB 1400 (SVL 170 mm, MBD 3.5 mm) with two large eggs (20 x 4, 21 x 3.5) on 22 November 1957. TM 57956 (SVL 178 mm, MBD 4 mm) with small vitellogenic ova (1.5 x 1 mm, 1.25 x 1 mm) on 23 July 1984. NMZB 2967 (SVL 202 mm) lacking vitellogenic ova in May, 1959.

Leptotyphlops macrorhynchus ( mean based on five males, BH uncat., CAS 105928 , 105400 , FMNH 21033 , MCZ 74163, NMW 17131–5, and six females, CAS 105926 , 105930 , 157118 , FMNH 26355 , MVZ 200827 )

Posterior tip of sternohyoideus 10.9%, sternohyoideus-heart gap 0.18, heart 3.8% (MP = 15.2%), snout-heart interval 17.1%, heart-liver gap 7.0%, liver convoluted with multipartite, subtriangular segments having their posterior apices overlapping their neighbors, vena cava zig-zag, right liver 42.0% (MP = 45.1%) with 54.3 (34–68) segments, left liver 28.6% (MP = 40.8%) with 41.2 (16–71) segments, postcaval vein undulating between liver lobes, anterior liver extension 0.06, posterior liver tail 0.26, left liver = 0.68 right liver, liver-gall bladder gap 3.1%, gall bladder 1.0% (MP = 69.7%) adjacent to or craniad of pancreas (1.4%), caudad of juxtasplenic body (1.7%) and cranialmost spleen (0.7%), pancreas with splenic limb, testes multipartite, right testis 4.9% (MP = 80.9%) with 15.6 (8–21) segments, left testis 3.9% (MP = 83.9%) with 14.8 (7–18) segments, right ovary 2.9% (MP = 82.1%) with 1.6 (1–3) ova and 4.4 (4–5) follicles, left ovary 2.9% (MP = 84.7%) with 1.7 (1–4) ova and 2.8 (1–6) follicles, right adrenal MP = 84.7%, left adrenal MP = 86.9%, kidneys compact but segmented, right kidney 3.5% (MP = 88.9%) with 6.6 (4–9) segments, left kidney 3.7% (MP = 91.6%) with 6.0 (3–9) segments, kidney-vent interval 12.8%, kidney-vent gap 6.6%, kidney overlap 0.18, rectal caecum vestigial (0.7%), tapering cranially and less than or equal to diameter to adjacent small intestine, caecumvent interval 7.3%.

Respiratory system lacking tracheal lung and left lung complex, trachea 16.3% (MP = 9.0%), estimated number of tracheal rings 227.2 (193–290) or 138.8 rings/10% SVL, anterior lung tip 15.4%, cardiac lung 1.7%, tracheal entry terminal, right lung 20.7% (MP = 27.5%), cranial half with two tiers of thick-walled faveolar parenchyma, caudal half narrow and reticulate with network of trabeculae, posterior tip 37.9%, bronchus 14.4%, posterior tip of bronchus 37.9%, bronchus = 0.71 right lung, trachea-bronchus 30.7% (MP = 16.2%), total lung 22.4% (MP = 26.6%).

Reproduction. Wallach (1998b) estimated the clutch size as 1–7. BH uncat. (SVL 140 mm, MBD 1.5 mm) with 1/0 vitellogenic ovum (2.5 x 0.75 mm) and 3/5 follicles on 5 April 199; CAS 105930 with 4/3 vitellogenic ova and 1/0 follicle on 7 May 1967; CAS 105926 (SVL 196 mm, MBD 2.3 mm) with 2/2 ova (1.5 x 0.75 mm) and 2/4 follicles on 7 May 1967; CAS 157118 (SVL 162 mm, MBD 1.5 mm) with 1/1 ova (5 x 1 mm) and 1/4 follicles on 28 September 1982; MVZ 200827 (SVL 130 mm) with 1/ 1 eggs (3.5 x 0.75 mm) and 4/5 follicles (date unknown) and FMNH 26355 (SVL 216 mm) with 1/ 1 eggs (4.0 x 1 mm /4.5 x 1 mm) and 6/ 4 follicles (date unknown).

Leptotyphlops nursii ( mean based on two males, FMNH 66157 , 66159 , and four females, BMNH 1905.11 .7.40, CAS 135251 , 140392 , FMNH 66158 )

Posterior tip of sternohyoideus 12.1%, sternohyoideus-heart gap 0.15, heart 3.9% (MP = 16.1%), snout-heart interval 18.1%, heart-liver gap 7.5%, liver lobes multipartite, right liver 39.1% (MP = 45.1%), with 46.0 (29– 66) segments, left liver 32.2% (MP = 44.5%) with 36.6 (25–52) segments, anterior liver extension 0.08, posterior liver tail 0.11, left liver = 0.82 right liver, liver-gall bladder gap 2.4%, gall bladder 1.2% (MP = 67.6%) wedged between caudal pancreas (1.4%) and elongate cranial juxtasplenic body (1.9%), spleen not apparent, testes multipartite, right testis 3.0% (MP = 80.5%) with 9.5 (9–10) segments, left testis 3.3% (MP = 82.0%) with 8.0 (8–8) segments, right ovary 2.7% (MP = 80.3%) with 2.3 (0–6) ova and 8.0 (7–10) follicles, left ovary 2.3% (MP = 79.5%) with 0.7 (0–2) ova and 6.3 (6–7) follicles, right adrenal MP = 83.3%, left adrenal MP = 84.6%, kidneys segmented with single renal artery, right kidney 3.5% (MP = 85.7%) with 8.0 (5–10) segments, left kidney 3.7% (MP = 88.5%) with 7.0 (4–9) segments, kidney-vent interval 16.1%, kidney-vent gap 9.7%, kidney overlap 0.15, rectal caecum 1.5%, 3–4 times the diameter of adjacent small intestine, caecum-vent interval 10.2%.

Respiratory system lacking tracheal lung and left lung complex, trachea 17.2% (MP = 9.5%) with an estimated 193.3 (160–270) tracheal rings or 112.8 rings/10% SVL, anterior tip of lung 16.2%, cardiac lung 1.8%, tracheal entry terminal, right lung 24.7% (MP = 30.4%), cranial third with 2 layers of faveoli, mesial third trabecular, caudal third of lung expanded and avascular, posterior tip of lung 42.7%, bronchus 16.8%, posterior tip of bronchus 35.6%, bronchus = 0.68 right lung, trachea-bronchus 33.9% (MP = 17.8%), total lung 26.5% (MP = 29.5%).

Reproduction. Wallach (1998b) estimated the clutch size as 7. FMNH 66158 (SVL 172 mm, MBD 2.75 mm) with vitellogenic ova on 20 January 1951. CAS 135251 lacking enlarged ova before May, 1972.

Leptotyphlops tanae ( mean based on male holotype, MCZ 40103, and paratype, MCZ 40093)

Posterior tip of sternohyoideus 16.0%, sternohyoideus-heart gap 0.03, heart 4.4% (MP = 18.7%), snout-heart interval 20.8%, heart-liver gap 10.2%, liver lobes multipartite, right liver 39.7% (MP = 50.8%), with 37.0 (34–40) segments, left liver 35.6% (MP = 49.1%) with 34.0 (30–38) segments, anterior liver extension on left (0.015) or right (0.03) lobe, posterior liver tail 0.10, left liver = 0.90 right liver, liver-gall bladder gap 1.5%, gall bladder 1.5% (MP = 72.8%) craniad of pancreas (1.7%), testes multipartite, right testis 4.7% (MP = 87.2%) with 10.0 (9–11) segments, left testis 4.1% (MP = 88.9%) with 11.0 (10–12) segments, right adrenal MP = 86.9%, left adrenal MP = 88.0%, kidneys compact but segmented, right kidney 3.5% (MP = 90.4%) with 5 segments, left kidney 3.8% (MP = 92.3%) with 6 segments, kidney-vent interval 11.4%, significant kidney overlap (0.34), kidney-vent gap 5.9%, rectal caecum 1.2%, equal in diameter to adjacent small intestine, caecum-vent interval 7.3%.

Respiratory system lacking tracheal lung and left lung complex, trachea 19.7% (MP = 11.0%) with an estimated 149.0 (148–150) tracheal rings or 75.7 rings/10% SVL, anterior tip of lung 19.1%, cardiac lung 1.8%, tracheal entry terminal, right lung 33.6% (MP = 37.6%), narrow with one layer of edicular parenchyma, posterior lung very narrow, posterior tip of lung 54.4%, bronchus 19.5%, posterior tip of bronchus 40.3%, bronchus = 0.60 right lung, trachea-bronchus 39.2% (MP = 20.7%), total lung 35.3% (MP = 36.8%).

Everted hemipenis of MCZ 40108 (SVL 76 mm, tail 7 mm, MBD 1.2 mm): organ single, filiform, 3 subcaudals in length (1.2 mm long, 0.1 mm diameter), basal 2/5 with slight expansion and a pair of lateral flaps or flanges, distal 3/5 nude with slightly tapering stem, apical surface expanded like a musical mouthpiece, sulcus simple and straight, extending along posterior surface of organ.