Trogolaphysa jacobyi Soto-Adames & Taylor

Soto-Adames, Felipe N. & Taylor, Steven J., 2013, The dorsal chaetotaxy of Trogolaphysa (Collembola, Paronellidae), with descriptions of two new species from caves in Belize, ZooKeys 323, pp. 35-74 : 45-52

Trogolaphysa jacobyi Soto-Adames & Taylor sp. n. Figs 24-43; Fig. 44 (habitat)

Type locality.

BELIZE: Toledo District: 32 km WNW of Punta Gorda, Yok Balum Cave, 13.IV.2012, SJT, MES, JJ, CMS, GBH & AC, coll.

Type material.

Holotype, female on microscope slide preparation, INHS collection number 579,407; BELIZE: Toledo District: 32 km WNW of Punta Gorda, Yok Balum Cave, 13.IV.2012, SJT, MES, JJ, CMS, GBH & AC, coll.; Paratypes: BELZE: Toledo District: 32 km WNW of Punta Gorda, Yok Balum Cave, 13.IV.2012, (2 adults & 1 juvenile on slides, 3 adults or subadults & 3 juveniles in alcohol), SJT, MES, JJ, CMS, GBH & AC, coll.; 37 km WNW of Punta Gorda, cave near Pueblo Creek Cave, 16.IV.2011, (1 adult on slide-without legs), MES, JKK, CMS, GBH & GeC, coll.

Diagnosis.

Trogolaphysa jacobyi sp. n. is the only member of the genus that is blind, has 3-toothed mucro and unguis, and has a single macrochaeta on the metathorax. Trogolaphysa belizeana is the only other New World Trogolaphysa lacking eyes and having a 3-toothed mucro, but it differs from Trogolaphysa jacobyi sp. n. in having 3 metathoracic macrochaetae (1 in Trogolaphysa jacobyi sp. n.), in the arrangement and identity of inner macrochaetae on Abd. 4 (cf. Figs 38, 49 see discussion below), in having few postlabial scales (absent in Trogolaphysa jacobyi sp. n.) and setae (many in Trogolaphysa jacobyi sp. n., cf. Figs 30, 46), in the presence of sensillum d2 on Abd. 3 (absent in Trogolaphysa jacobyi sp. n.), in the absence of unpaired ungual teeth (1 tooth in Trogolaphysa jacobyi sp. n.) and in having a typical lanceolate unguiculus (basally swollen in Trogolaphysa jacobyi sp. n.). Table 3 provides a list of characters that distinguish Trogolaphysa jacobyi sp. n. from all other New World Trogolaphysa lacking eyes and having paired basal ungual teeth inserted near the basal fourth of the inner edge.

Description.

Size. Body length up to 2.0 mm.

Color. Living specimens yellowish, with pigment only on a small eyepatch and mesothorax (Fig. 24). Specimens in alcohol white, without trace of pigment.

Scale distribution. Scales transparent, present on Ant. 1-2. Scales absent from postlabial region of head, ventral tube, legs and dorsal face of manubrium.

Head. Antenna/cephalic diagonal ratio up to 5.8 (Fig. 24). Fourth antennomere with incomplete but clear constriction near middle, with many shallow whorls of setae (Fig. 25); apical bulb absent; subapical sensillum not seen. Sense organ of Ant. 3 with sensilla 1 and 4 short, acuminate, thin-walled and translucent; sensillum 5 acuminate, dark and shorter than 1 and 4; sensilla 2-3 broad, leaf-like, resting in shallow grooves. Eyes not seen on slide-mounted specimens, but 1-2 pigment patches visible in life (Fig. 24). Head dorsally with 8 macrochaetae (A0, A2, A3, M3, S3, S5, Pa5 and Pm3 - Fig. 26). Seta M4 displaced laterally towards cephalic sulcus. Series S with setae S1-5; S0 absent, macrochaeta S3 displaced anteriorly, away from cephalic sulcus (cf. Figs 5, 26). Prelabral and all labral setae smooth: setae within row A and C subequal; seta B2 shorter than B0 and B1 (Fig. 27). Distal margin of labrum smooth, papillae absent. Apical and subapical setae of maxillary palp smooth; sublobular plate without seta-like appendages. Lateral process of labial papilla E weakly bent dorsally and not nearly reaching apex of papilla (Fig. 28). Labial triangle setae as M1M2rEL1 –2A1– 5 (Fig. 29), seta M1 ciliate, all others smooth; r short; A2 close to r, L1 close to E and distant from L2. Postlabium without scales, polychaetotic, uniformly covered with many large and small, weakly ciliate or smooth setae (Fig. 30); modified setae absent. Columns ICELO ill defined due to polychaetosis. Ventral cervical setae usually 6+6.

Body. Mesothoracic hood not developed. Complete dorsal macrochaetae as 62/41/0244+0+9-11. Mesothorax with 1 anterior (a5) and usually 3 posterior (p1-3) macrochaetae forming an arch (Fig. 31); some individuals with only mesothoraxic macrochaeta p2 (Fig. 32); microchaetae m1, m2, m4, p4 and p5 present. Metathorax with 1 macro- and 5 microchaetae (Fig. 33). First abdominal segment seta a6 absent; 4 posterior setae arranged in a single row (Fig. 34-36). Inner bothriotrix complex of Abd. 2 with 3 fan-shaped setae, one microsensillum and macrochaeta m3; outer bothriotrix with 3 fan-shaped setae and macrochaeta m5; setae a6, m6 and p5 present. Inner bothriotrix complex of Abd. 3 with 3 fan-shaped setae, one sensillum and macrochaetae m3; external bothriotrichal complex (Fig. 37) with 6-7 fan-shaped setae, macrochaetae am6, pm6 and p6; sensillum d2 absent. Fourth abdominal segment with 4 inner (Fig. 38) and 9-11 outer (Fig. 39) macrochaetae: inner macrochaetae A5, B4, and B5 large, B6 small; B5 displaced towards A6 instead of B6; (Fig. 38). Outer macrochaetae D3, E2, E3, F1, and F2 large; small outer macrochaetae E4, F3, F4 and 3 others probably belonging to series Fe present. Abd. 4 anterior and medial bothriotricha with 4 and 2 fan-shaped supplementary setae, respectively (Fig. 39). Posterior bothriotrix corresponds to D4, without associated supplementary setae. Posterior setae 6 –7+6– 7. Intersegmental membrane between Abd. 4-5 with 4-7 lenticular organs.

Legs. Trochanteral organ with up to 25 setae. Claw complex as in Figs 41-42. Tenent hair acuminate, longer on L1 than L3. Smooth posterior setae on metathoraxic legs as long as unguiculus. Unguis with 3 inner teeth: basal teeth small, subequal and ending on basal fourth of inner edge; unpaired tooth distinctly larger than basal teeth, ending near middle of inner ungual edge. Outer tooth absent on all claws; lateral teeth present only on pro- and mesothoracic legs, and ending on basal quarter of outer edge of unguis (Fig. 41). Unguiculus basally swollen, with basal fifth of outer margin weakly serrate.

Ventral tube.

Anterior face with 2+2 distal macrochaetae; lateral and posterior setae not seen.

Furcula. Dens with 2 rows of finely ciliate spines, number of spines per row unclear on all specimens examined, but inner row with at least 36 spines. Mucro elongate and slender, with 3 teeth, basal inner tooth absent (Fig. 43): ratio mucro length/width of dens tip 2.3-2.8 (mode=2.4).

Distribution.

The species is known only from caves in southern Belize

Remarks.

Trogolaphysa jacobyi sp. n. is a troglobiont (sensu Sket 2008, Culver and Pipan 2009). Living specimens seem to have eye pigment (Fig. 24), but we were unable to identify corneas on specimens examined. The only structure resembling a cornea corresponds to the EOS.

It could be argued that the constriction of the fourth antennomere places this species in Troglopedetes . However, the presence of a well-developed ciliate labial seta L2, the incomplete nature of the constriction on Ant. 4, and the similarity with Trogolaphysa belizeana (presumably with complete, unconstricted Ant. 4, and therefore an uncontested Trogolaphysa ) suggest that Trogolaphysa jacobyi sp. n. should be retained in Trogolaphysa . Additionally, the fact that all other Troglopedetes species are restricted to the Old World have prompted us to retain the new species in Trogolaphysa .

Etymology.

This species is dedicated to JoAnn Jacoby, the junior author’s wife, in gratitude for her enthusiasm and assistance in the planning and execution of field-work in the caves of Belize and in many earlier excursions.

Habitat.

This species is a troglobiont, and all 5 collections (11 individuals) were taken in the dark zone (0 lux) on the floor (Fig. 44), often (80% of collections) in wet conditions associated with flowstone or calcite and drip pools, sometimes with scattered cricket droppings.