Eustala orientalis, Baert, Léon, 2014

Baert, Léon, 2014, Three new Eustala (Araneae, Araneidae) species from the Galápagos Islands (Ecuador), European Journal of Taxonomy 86, pp. 1-18 : 9-12

Eustala orientalis sp. nov.

urn:lsid:zoobank.org:act:AF420B6B-A770-4731-908B-4ECF219861A9

Figs 3 A–E, 5 C, 6 C, 7

Eustala vegeta (Keyserling, 1865) . – Baert, Maelfait, Hendrickx & Desender 2008: 47, map 15 (misidentiFcation).

Eustala sp. – Baert 2013: 176, 178.

Diagnosis

Males differ from E. occidentalis sp. nov. by the structure of the terminal apophysis: Fat and broadening towards the tip, its caudal ridge being longer than the apical ridge. Females differ from E. occidentalis sp. nov. by the shape of the scapus.

Etymology

The species name refers to its distribution in the eastern part of the archipelago.

Type material

Holotype

Ƌ, ISLA ESPAÑOLA, 1 km W of Punta Cevalos beach, vegetation of beach berm: Valessia, Grabowskia , Prosopis , Cordia , 7 Feb. 1977, leg. W.G. Reeder .

Allotype

♀, ISLA ESPAÑOLA, 1 km W of Punta Cevalos beach, vegetation of beach berm: Valessia, Grabowskia , Prosopis , Cordia , 7 Feb. 1977, leg. W.G. Reeder .

Paratypes

ISLA ESPAÑOLA: 1 Ƌ, Bahía Gardner, Playa blanca , 27 Apr. 1991 (B.91/0742) (leg. Baert, Maelfait & Desender, 1991) ; 1 ♀, 2 (♀♀), Caleta at Bahía Manzanilla , 21 Mar. 2009 (B.09/014-15) ; 2 ƋƋ, 6 ♀♀, 3 (ƋƋ), # j(s), 1 km W of Punta Cevalos beach, vegetation of upper beach: Valessia, Grabowskia , Prosopis , Cordia , 7 Feb. 1977 (leg. W.G. Reeder) ; 1 Ƌ, Punta Suarez, albatros colony , 28 Feb. 1977 (leg. W.G. Reeder) .

ISLOTE GARDNER near ESPAÑOLA: 2 ♀♀, alt. 10–30 m, through Bursera , Croton , Alternanthera , and ferns , 12 Feb. 1977 (leg. W.G. Reeder) ; 1 ♀, alt. 30 m, from Croton in Bursera -Opuntia - Cordia - Croton community , 12 Feb. 1977 (leg. W.G. Reeder) .

RBINS inventory number of all type material is I.G. 32724.

Other material examined from the islands of Genovesa, San Cristóbal and Santa Fé (see Table 2 ).

Description

Male (holotype)

LENGTH. Total length 5.06; carapace length 2.67, width 2.16, height 0.90; abdomen length 3.41, width 2.27, height 1.96.

CARAPACE. Colour (in alcohol) yellow brown with clypeus and eye region black, dorsal cephalic part yellow brown with central, faintly suffused, blackish V; two short combs of long white hairs diverge from between PME and PLE. Chelicerae yellow with central, faintly suffused, blackish stain. Labium and endites pale yellow with white margin. Sternum yellow with faintly suffused, blackish stains in front of coxae. Pedipalps yellow-brown with some black stain. Legs pale yellow with black annulations, variable between specimens; coxae and proximal part of femora whitish.

ABDOMEN. Dorsum creamy white with small, black median triangle in front, two small, white central stains and distinct dark sepia folium with dark brown margins and ten brown apodemes arranged as 4-2-2-2, becoming smaller caudally and towards the sides; venter whitish, slightly suffused with black; colulus and spinnerets dark.

EYES. MOQ: PME = 0.8 AME. Cl = 0.5 DAME.

LEGS. Measurements:

I (13.09): Fe 4.12, Pa 1.37, Ti 3.25, Mt 3.10, Ta 1.25 II (9.97): Fe 3.06, Pa 1.14, Ti 2.12, Mt 2.55, Ta 1.10 III (5.89): Fe 2.12, Pa 0.78, Ti 1.14, Mt 1.14, Ta 0.71 IV (8.94): Fe 3.10, Pa 1.10, Ti 1.88, Mt 2.04, Ta 0.82

SPINATION. All legs with numerous spines.

PEDIPALP ( Figs 3 A–B, 5C). One very long patellar seta, slightly longer than bulbus. Cymbium with conspicuous, rounded, T-shaped tarsal hook. Terminal apophysis ( Fig. 6 C) short, caudal ridge being longer than apical ridge, Fat and broadening towards tip.

Female (allotype)

LENGTH. Total length 7.10; carapace length 3.10, width 2.67, height 1.06; abdomen length 4.47, width 4.16, height 3.14.

CARAPACE. As in male, but with more pronounced orange tinge.

ABDOMEN. As in male, but more uniform grey; shoulders white; venter sepia with white stains; spinnerets orange brown.

EYES. MOQ: PME = 0.88 AME. Cl = 0.77 DAME.

LEGS. Measurements:

I (13.26): Fe 4.12, Pa 1.57, Ti 3.18, Mt 3.06, Ta 1.33 II (11.18): Fe 3.25, Pa 1.45, Ti 2.55, Mt 2.20, Ta 1.73 III (6.81): Fe 2.31, Pa 1.02, Ti 1.29, Mt 1.33, Ta 0.86 IV (10.32): Fe 5.57, Pa 1.37, Ti 2.16, Mt 2.24, Ta 1.98

EPIGYNE ( Fig. 3 C–E). Length of scapus 0.47, diameter (lateral view) 0.16, L/D = 4.8. Spermathecae separated; scapus broader at tip (in ventral view), straight, evenly broad (in lateral view).

Variation

The males in our samples vary in length between 4.6 and 6.9 mm, the females between 5.1 and 8 mm.

The colour variation of the abdomen is comparable to that of the previous species.

Distribution

E. orientalis sp. nov. has an eastern distribution within the archipelago ( Fig. 7 ): Española (arid zone), Islote Gardner near Española, Genovesa (arid zone), San Cristóbal (coastal arid zone and above 500 m alt.) and Santa Fé. We cannot detect a preference for a certain kind of vegetation zone, as most islands are low in altitude.

Figures

Fig. 3. Eustala orientalis sp. nov. A. Ƌ left palp, ventral view. B. Ƌ left palp, apical view. C. ♀ scapus, lateral view. D. ♀ epigyne scapus, ventral view. E. ♀, spermathecae. Scale lines = 0.5 mm.

Fig. 6. Electron microscopic photographs of terminal apophysis of Ƌ left palp. A. Eustala occidentalis sp. nov. B. Eustala meridionalis sp. nov. C. Eustala orientalis sp. nov. Scale lines = 0.1 mm.

Fig. 7. Distribution map of Eustala occidentalis sp. nov., Eustala occidentalis sp. nov. and Eustala meridionalis sp. nov.

Tables

Table 2. Other material examined of Eustala orientalis sp. nov. Abbreviations: GEN: Genovesa, SCB: San Cristóbal, SFE: Santa Fé; Ƌ: male, (Ƌ): subadult male, ♀: female, (♀): subadult female, j (s): juvenile (s).

Island	Locality	Altitude	Date	Sex	Leg.
GEN	500 m W of Playa Bahía Darwin	10–15 m	23 Oct. 1975	3♀♀ 1(Ƌ) 4(♀) 4j (s)	75/ WGR
GEN	500 m SE of crater rim	50 m	25 Oct. 1975	1j ♀	75/ WGR
GEN	Lago Arcturus	60 m	13 Mar. 1988	1Ƌ	88/ LB,JPM,KD
SCB	Wreck Bay area, upper beach vegetation	5 m	9 Feb. 1975	1Ƌ 1♀	75/ WGR
SCB	Cerro Mundo	550 m	13–23 Feb. 1989	1Ƌ	89/ SP
SCB	El Junco (near Cabo Guido Rosillo)	600 m	18 Feb. 1978	3Ƌ 1 ♀ 2j (s)	78/ WGR
SFE	Camp area	5– 10 m	24 Jan. 1979	2Ƌ	79/ WGR
SFE		50–100 m 100 m	1–2 Apr. 1982	1♀	82/ LB,JPM
SFE	1 km SSW of camp beach, second arranco		24 Jan. 1979	1j	79/ WGR