Entomobrya citrensis Katz & Soto-Adames

Katz, Aron D., Giordano, Rosanna & Soto-Adames, Felipe, 2015, Taxonomic review and phylogenetic analysis of fifteen North American Entomobrya (Collembola, Entomobryidae), including four new species, ZooKeys 525, pp. 1-75 : 22-26

Taxon classification Animalia Collembola Entomobryidae

Entomobrya citrensis Katz & Soto-Adames sp. n. Figs 2, 14, 15, 16A

Etymology.

This species is named after the locality it was collected in: Citrus County, Florida. Citrensis is Latin for "from the place of citrus".

Type material.

Holotype, ♂, USA: Florida, Citrus County, Chassahowitzka National Wildlife Refuge (28.75997,-82.57583), beating vegetation, 12.viii.2011 (A. Katz & J. Cech), AK11-134.

Paratypes, USA: 1 on slide, Florida, Citrus Co., Chassahowitzka National Wildlife Refuge (28.75997,-82.57583), under bark, 12.viii.2011 (A. Katz & J. Cech), AK11-136; 1 on slide, Florida, Citrus Co., Chassahowitzka National Wildlife Refuge (28.75997,-82.57583), beating vegetation and in leaf litter, 5.i.2014 (A. Katz & M. DuBray), AK14-1.

Description.

Body shape and color pattern. Body dorso-ventrally flattened. Length up to 1.4mm. Color pattern monomorphic (Fig. 14): background white, or slightly yellow, with black and traces of dark brown pigmentation forming transversal bands and spots. Thorax dorsal pigmentation patchy and irregular. Abd. 2 usually with 2 dark lateral spots. Posterior margin Abd. 2 and the anterior margin of Abd. 4 with a dark transverse band. Abd. 4 with a conspicuous irregular dark transverse band medially. The antennae are completely pigmented purple.

Head. Apical bulb of 4th antennal simple. Long differentiated smooth setae on ventral side of 1st antennal segment ≈2.5 × short setae. Prelabral setae with very fine ciliations that look smooth at low magnification under light microscopy. Ornamentation of the distal margin of the labral papillae with 3-4 spine-like projections on the inner papillae and 2 spine-like projections on the external papillae. Lateral appendage of labial papilla E slightly curved, relatively thin, reaching just below tip of papilla. Dorsal head chaetotaxy slightly reduced (Fig. 15A): macrosetae An’ 0, A6, M3, M3i, S’ 0, S1, Pi1, Pa2, Pa3, Pm2, and Pm1i always absent; An3a3 present, asymmetrically absent in one specimen. Eyes G and H small and subequal. Eye patch with 5 setae.

Thorax. Thoracic chaetotaxy reduced and fixed, no macrosetae variation observed. Row of microsetae along entire posterior margin of Th. 2 and Th. 3 (not displayed in figures). Th. 2, with a5 and posterior macrosetae p4, p5, p6, p6e, and p6ep (Fig. 15B). Th. 3, with 7 macrosetae present: a5, a6, m5, m6, m7, p4, and p6; macrosetae a1, a2, and a3 absent (Fig. 15C). Zone Pm (Fig. 3) without macrosetae.

Legs. Trochanteral organ with triangular setal pattern and up to 14 setae. Unguis with 4 internal teeth; basal teeth located approximately middle of inner claw length (Fig. 16A).

Abdomen. Abdominal chaetotaxy reduced and stable; no macrosetae variation observed. Abd. 1 with 1 macroseta only (Fig. 15D). Abd. 1 row of microsetae along posterior margin is present (not displayed in figure). Abd. 2 with 4 macrosetae: a3, m3, m3e, and m5 (Fig. 15E). Abd. 3 with 4 macrosetae: a2, m3, pm6, and p6; mesosetae a2a sometimes present, inserted slightly anterior and exterior to a2; socket of a2a large, resembling that of macroseta a3, but its close proximity to a2 suggests a duplication of a2 rather than homologous to a3 (Fig. 15F). Abd. 4 with 4 inner macrosetae (Fig. 15G). Mucronal teeth subequal.

Remarks.

Entomobrya citrensis sp. n. can be distinguished by its color pattern in combination with the absence of Th. 2 macrosetae m2 and m5, Abd. 2 a2 and m3ep, and the presence of Abd. 2 a3 (see Table 2 for additional diagnostic characters).

This species is closely related to Entomobrya assuta ; both have highly compressed, or dorso-ventrally flattened bodies, reduced chaetotaxy, and similar color patterns. Head macroseta Ps3 and Abd. 2 macroseta a3 are both present in Entomobrya citrensis sp. n., but are absent in Entomobrya assuta . These species can also be separated by color pattern and morphology of the labral papillae (Fig. 2).

See remarks for Entomobrya assuta for additional diagnosis information. Only a few specimens of Entomobrya citrensis sp. n. were observed from one locality. Additional sampling may reveal more variation in color pattern or chaetotaxy.

Distribution.

Endemic to North America. Reported from a single locality: Chassahowitzka National Wildlife Refuge in Citrus County, Florida (Suppl. material 2: D).