Gialaia (Eugialaia) strasbergi Hugel

Hugel, Sylvain, 2014, Burrowing crickets endemic to summits in Mauritius (Orthoptera, Gryllidae): occupation of similar niches by species possibly derived from Australasian and African colonists, Zootaxa 3852 (3), pp. 382-390 : 386-388

Gialaia (Eugialaia) strasbergi Hugel n. sp.

( Figs. 11–20 ; Tab. 2 )

Holotype. Male. Mascarene archipelago, Mauritius, [Savanne District, Black River National Park], Montagne Cocotte; 740 m alt.; 20°26.5’S 57°28.4’E; 23. II.2008; D. Strasberg leg. (BIOTAS 2008 400), MNHN (MNHN- EO-ENSIF3731).

Paratypes. All localities as holotype. Females. 23.II.2008, S. Hugel leg. (BIOTAS 2008 401), MNHN (MNHN-EO-ENSIF3732); 6.III.2008, S. Hugel leg. (BIOTAS 2008 112), SH coll; 6.III.2008, S. Hugel leg. (BIOTAS 2008 113), SH coll; 7.V.2009, S. Hugel leg. (BIOTAS 2009 173), SH coll; 7.V.2009, S. Hugel leg. (BIOTAS 2009 387), SH coll.

Diagnosis. Gialaia (Eugialaia) strasbergi n. sp. is distinguished from all other Gialaia by combination of the following: size large ( Table 2 ); eyes very small ( Fig. 11–12 ); wings totally absent; pronotum with convex lateral margins and concave on anterior and posterior margins; male epiphallic sclerite with a short median projection, with short lophi, with wide space between lophi.

Description. Male. Head and antennae: eyes small, not protruding, separated by>2.5 times their diameter (dorsal view; Fig. 11 ); rostrum>2.5 times wider than scapus (dorsal view; Fig. 11 ); maxillary palpi 4th article as long as the 3rd article, apex of 5th article moderately enlarged. Thorax. Pronotum distinctly wider than long ( Fig. 11 ); trapezoidal: wider anteriorly than posteriorly; mesosulcus not distinct; with a longitudinal depression; posterior and anterior margins concavous; lateral margins convex. Legs. Tympana lacking on both sides of fore tibia. Fore tibia enlarged distally. Fore and mid tibia with 1 ventral inner spur; 1 ventral outer spur, 1 dorsal inner spur, 1 dorsal outer spur. Hind femora 2.6 times longer than wide. Hind tibia 0.6 times as long as hind femora. Hind tibia with 3 inner and 3 outer apical spurs ( Fig. 13–14 ); with 4 outer subapical spurs, with 4 inner subapical spurs strongly enlarged ( Fig. 13–14 ). Hind basitarsus with 5 outer and 4 inner dorsal spines ( Fig. 13–14 ). All leg tarsi with strong short ventral setae. Genitalia. Epiphallic sclerite symmetrical, with broadly separated lophi projecting posteriorly ( Fig. 15 ); with a short median process. Pseudepiphallic parameres broadly rounded posteriorly, not exceeding the distal end of lophi ( Fig. 15–17 ). Female. As males except: hind tibia inner subapical spurs not modified. Terminalia. Ovipositor as long as hind femora, moderately up curved ( Fig. 20 ). Copulatory papilla fusiform ( Fig. 18–19 ). Color: back ground color of head dark brown; with light brown in: clypeus, labrum, retroocular line, interocellar line, occipital tripes. Pronotum with dark brown lateral lobes and light discus with dark patterns. Abdomen tergites light brown with dark patterns. Legs light brown with dark patterns; hind femora outer field striped.

Biology. The first specimen of Gialaia (Eugialaia) strasbergi n. sp. was collected by a botanist while uprooting a small plant. All specimens have been found burrowing underground galleries within the soft soil between the buttresses roots at the basis of one single endemic Syzygium sp. tree. Adults have been observed together with many juvenile specimens. Since 2008, I regularly visited the station, and always observed the species (mostly juveniles).

Etymology. Gialaia (Eugialaia) strasbergi n. sp. is named after the Mascarene botanist Dominique Strasberg who collected the first specimen and only known male of the species.

Figures

FIGURES 11 – 14. Gialaia (Eugialaia) strasbergi n. sp. 11, dorsal view of male holotype; 12, frontal view of face; 13, right hind tibia, outer view; 14 right hind tibia, inner view. Scale bars: 11: 10 mm; 2 – 4: 1 mm.

FIGURES 15 – 20. Gialaia (Eugialaia) strasbergi n. sp. 15 – 17, male holotype genitalia in dorsal view; 15, right side view; 16, ventral view; 1 7. 18 – 20 female genitalia; 18 – 19 copulatory papilla in left side view; 18 and ventral view; 19. 20, female last abdominal tergites in side view. Scale bars: 1 mm.

Tables

TABLE 2. Measurements (mm) of Gialaia (Eugialaia) strasbergi n. sp.

Total Head Head Pro	Pro	F1	F2	F3	F3	T3	Bt	O
L L W L	W	L	L	L	W	L	L	L
Male Holotype 10.5 1.3 2.8 1.8	3.1	2.2	2.5	6.3	2.4	3.7	2.1
Average females (5) 12.3 1.9 3.1 2.3	3.5	2.6	2.5	6.9	2.5	4.2	2.3	6.0
Min females 11.0 1.6 2.9 2.0	3.1	2.2	2.3	6.3	2.4	3.9	2.1	5.5
Max females 15.1 2.2 3.2 2.7	3.6	3.2	2.6	7.4	2.7	4.4	2.6	6.8
L: length; W: width.