Ero lizae Sherwood & Henrard & Peters & Price & Hall & White & Grignet & Wilkins 2024, sp. nov.

Ero lizae sp. nov.

urn:lsid:zoobank.org:act: 8AF98DA2-DF2C-4C55-9823-294E4A99EFAB

Figs 1–9

Ero aphana – Unzicker 1977: 127–129 (misidentification).

Diagnosis

Ero lizae sp. nov. can be distinguished from all presently known congeners based on the presence of two large spike-like protuberances on the dorso-posterior opisthosoma (Figs 2, 4A–D, 6A) (dorso-posterior opisthosoma without two large spike-like protuberances in all other known congeners). Further distinguished from the male of E. aphana by palp morphology, with the ventral blade twice the length of the dorsal extensions and lower dorsal extension little more than half the length of upper dorsal extension (Figs 3, 5A–B, 6F, 7) (ventral blade less than twice the length of the dorsal extensions and lower dorsal extension more than half the length of upper dorsal extension in E. aphana). Also distinguished further from males of E. natashae sp. nov. by non-hooked retrolateral cymbial process and the wider and less developed conductor (retrolateral cymbial process hooked and conductor thinner and more developed in E. natashae). The female can be distinguished from that of E. aphana by the presence of spike-like protuberances (see above) and further by epigynal morphology, with a smaller atrium and the scape ending beyond the anterior atrium (Figs 4E–F, 5C–D, 6C–E, 7) (atrium larger and scape ending before the anterior atrium in E. aphana). Further distinguished from those of E. natashae by the wider copulatory openings and anteromedian plate slightly protruding, not medially crossed by a thin septum (copulatory openings narrower and anteromedian plate strongly protruding, medially crossed with a thin septum in E. natashae). Additionally, Ero lizae is genetically distinct from those taxa for which COI barcodes exist on BOLD by a genetic difference of 11.7% (Fig. 1).

Etymology

The specific epithet is a matronym honouring Saint Helenian conservationist Liza Fowler (Saint Helena National Trust) in recognition of her more than ten years of service to the protection of endemic invertebrates on the island. The senior author’s expedition to Saint Helena would not have been nearly as successful without her hard work, knowledge, and encouragement.

Material examined

Holotype

UNITED KINGDOM – Saint Helena, Ascencion and Tristan da Cunha • ♂; Actaeon Peak [= Mt Actaeon], Saint Helena; 16 Dec. 2005 – 9 Mar. 2006; P. Ashmole and M. Ashmole leg.; B3; 6312/C; [NHMUK AQ ZOO-2022-84]; NNHMUK 015134292.

Paratypes

UNITED KINGDOM – Saint Helena, Ascencion and Tristan da Cunha • 1 ♀; same collection data as for holotype; [NHMUK AQ ZOO-2022-84]; NNHMUK 015134292 • 1 ♀; Cuckhold’s Point, Saint Helena; 15°58′15.5″ S, 5°42′11.6″ W; alt. 221 m; 9 Feb. 2006; P. Ashmole and M. Ashmole leg.; P. Ashmole and M. Ashmole coll.; night visit; 6298; NHMUK AQ ZOO 2022-84 • 1 imm. ♂; Deep Valley Head, Saint Helena; off Black Scale Fern; 12 Jan. 2006; H. Mendel, P. Ashmole and M. Ashmole leg.; P. Ashmole and M.Ashmole coll.; 6285/C; NHMUK AQ ZOO 2022-84 • 1 ♀; High Central Ridge, Cabbage Tree Road, Saint Helena; alt. 701–792 m; 6 Feb. 1967; J. Decelle and N. Leleup leg.; BE_RMCA_ARA. Ara.133384 • 1 ♂, 1 ♀; same collection data as for preceding; Mar. 1967; BE_RMCA_ARA.Ara.133283 • 1 ♀; same collection data as for preceding; 22 Jan. 1967; BE_RMCA_ARA.Ara.133370 • 1 ♂; New Restoration, Diana′s Peak, Saint Helena; 15°58′13.2″ S 5°42′11.5″ W; Malaise trap; SHNT.

Other material

UNITED KINGDOM – Saint Helena,Ascencion and Tristan da Cunha • 1 imm.; High Central Ridge, Cabbage Tree Road, Saint Helena; alt. 701–792 m; Mar. 1967; BE_RMCA_ARA.Ara.133286 • 1 imm. Diana’s Peak, Saint Helena; 15°58′ S, 5°42′ W; 9 Feb. 1967; J. Decelle and N. Leleup leg.; Cuvette; BE_RMCA_ARA.Ara.133448.

Description

Male holotype

MEASUREMENTS. Total length including chelicerae: 4.01. Carapace: 2.06 long, 1.56 wide. Ocular tubercle: 0.23 long, 0.78 wide. PLE distinctly projecting over outer edge of carapace, ALE distinctly projecting over front of ocular tubercle. Chelicerae with 8 peg teeth. Stridulatory ridges absent. Opisthosoma: 1.91 long, 1.78 wide.

LEGS (femur + patella + tibia + metatarsus + tarsus). I 14.49 (4.13 + 1.05 + 4.31 + 3.37 + 1.63), II 8.51 (2.56 + 0.57 + 2.00 + 2.75 + 0.63), III 5.05 (1.97 + 0.43 + 1.00 + 0.85 + 0.80), IV 6.39 (2.29 + 0.64 + 1.74 + 0.93 + 0.79). Metatarsus I with 5 strong spines.

OPISTHOSOMA. With two pairs of spike-like protuberances, anterior pair smaller than posterior pair, which are profoundly enlarged (Fig. 2A–D).

PALP (Figs 3, 5A–B, 6F, 7). Tibia distally with retrolateral circular depression, cymbium medially with blunt retrolateral process (RP), paracymbium with two dorsal extensions and one ventral blade (VB), upper dorsal extension conical, tip rounded (UE), lower dorsal extension triangular (LE), ventral blade elongate (twice the length of dorsal extensions), rounded, embolus emergent proximally, twisted distally, conductor distally rounded (Figs 3, 5A–B).

COLOUR (in alcohol; Fig. 2). Carapace brown, with brown markings on lateral and posterior edges, brown blotches forming broken line medially behind ocular tubercle, and single, broken longitudinal brown line extending entire length of carapace medially; legs annulated; opisthosoma brown with black and cream blotches in posterior half; opisthosomal spike-like protuberances black on anterior faces and cream on posterior faces.

Female paratype (specimen from same tube as holotype)

MEASUREMENTS. Total length including chelicerae: 5.68. Carapace: 2.44 long, 1.77 wide. Ocular tubercle: 0.40 long, 1.04 wide. PLE projecting over outer edge of carapace, ALE slightly projecting over front of ocular tubercle. Chelicerae with 8 peg teeth. Stridulatory ridges absent. Opisthosoma: 2.78 long, 2.63 wide.

LEGS. I 14.75 (4.47 + 1.14 + 4.10 + 4.16 + 0.88), II 11.67 (3.00 + 0.92 + 2.63 + 3.41 + 1.71), III 6.55 (2.29 + 0.37 + 1.83 + 1.48 + 0.58), IV 7.78 (2.63 + 0.82 + 2.13 + 1.37 + 0.83). Metatarsus I with 5 strong spines.

OPISTHOSOMA. With two pairs of spike-like protuberances, anterior pair smaller than posterior pair (Fig. 4A–D).

EPIGYNE AND VULVA (Figs 4E–F, 5C–D, 6C–E, 8). Epigyne with thin median septum, outer edges of septum sclerotised, longitudinally concave, anteriorly outstripping copulatory openings, copulatory openings circular, with thick and strongly sclerotized anterior margins; vulva with two globular spermathecal receptacles (SR), each dorsally with antero-medial groove (Fig. 4E–F).

COLOUR (in alcohol; Fig. 4A–D). Carapace brown, with brown markings on lateral and posterior edges, brown blotches forming broken line medially behind ocular tubercle, and single, broken longitudinal brown line extending entire length of carapace medially; legs annulated; opisthosoma brown with black and cream blotches in posterior half; opisthosomal spike-like protuberances black on anterior faces and cream on posterior faces.

COLOUR IN VIVO (Fig. 9A–C). Carapace olive yellow, with black markings on lateral and posterior edges, two black blotches forming broken line medially behind ocular tubercle, and single, broken longitudinal black line extending entire length of carapace medially; legs annulated; opisthosoma olive yellow with black and white blotches in posterior half; opisthosomal spike-like protuberances black on anterior faces and white on posterior faces.

Distribution

Known only from the Peaks National Park, Saint Helena (Fig. 9D–E).

Remarks

Ero lizae sp. nov. has been found only in the cloud forest (Fig. 9D–E) and is presently only recorded from one specific plant, the endemic Black Scale Fern (Diplazium filamentosum). It is, however, likely to occur on other ferns, but this will require confirmation through future fieldwork. Diet, behaviour, and other aspects of its ecology are largely unknown presently and need to be studied in the future. Initial fieldwork efforts by DS have failed to find this species in non-cloud forest habitat, but future research is needed. Since we have multiple samples, we present additional plates of paratypes in RMCA, which show low intraspecific genitalic variation (Figs 5C–D, 6–8).