Dolichoiulus oromii, Enghoff, 2012

Enghoff, Henrik, 2012, Three new species of Dolichoiulus millipedes from the underground of Gran Canaria, with notes on the circumscription of the genus (Diplopoda, Julida, Julidae), European Journal of Taxonomy 15, pp. 1-12 : 5-9

Dolichoiulus oromii sp. nov.

Figs 2B , 3C , 4C , 5

Diagnosis

A blind species of Dolichoiulus . Differs from other blind Dolichoiulus species as shown in Table 1 . Differs from all other Dolichoiulus species, except D. blancatypa ( Enghoff, 1992) comb. nov., in having metazonital setae. Differs further from the other blind Dolichoiulus on Gran Canaria in size ( Figs 1 , 5 ), in having extensive preanal pilosity, and in lacking a terminal projection on the mesal ridge of the anterior gonopod. Differs from D. longunguis sp. nov. and the widespread D. typhlops in having slenderer anterior gonopods ( Fig. 3C , cf. Fig. 3D ). Differs from D. blancatypa (from Tenerife) in having the mesomerital process clearly separated from the opisthomerite.

Etymology

The species in named in honour of Pedro Oromí, La Laguna, Tenerife, in recognition of his vast effort to document and analyse the Canarian fauna.

Type locality

GRAN CANARIA (Canary Islands), El Sao.

Material studied

all from Canary Islands: Gran Canaria.

Holotype

♂, El Sao ( Agaete ), UTM 28 R 4354/31049 (28°04’06’’N, 15°39’27”W), MSS, 26 Dec. 2005, H. López leg. ( DZUL).

Paratypes

3 ♂♂, 2 ♀♀, same data. (2 ♂♂, 2 ♀♀ DZUL, 1 ♂ ZMUC); 1 ♂, same loc., May 2005, H. López leg. ( DZUL); 8 ♂♂, 3 ♀♀, 1 juv., same loc., 28 Dec. 2006, H. López leg. (1 ♂ 1 ♀ DZUL, 6 ♂♂ 1 ♀ 1 juv. ZMUC, 1 ♂ 1 ♀ MCNT); 2 ♀♀, same loc., 11 Aug. 2007, H. López leg. ( DZUL), 5 ♂♂, 1 ♀, same loc., 7 Jan. 2009, H. López leg. ( DZUL); 1 ♂, 1 ♀, same loc., 3 Jan. 2010, H. López leg. ( DZUL); 2 ♂♂, same loc., 4 Dec. 2010, H. López leg. ( DZUL).

Referred (non-type) material

1 ♀, Caldera de los Marteles, UTM 28R 4481/30920 (27°57’01’’N, 15°31’40”W), MSS, 19 Aug. 2006, H. López leg. ( MCNT); 1 ♀, same loc., 7 Nov. 2008, H. López leg. ( DZUL); 2 ♂♂, 5 ♀♀, same loc., 27 Dec. 2008, H. López leg. ( DZUL); 1 ♀, Los Majateles, UTM 28R 4505/30915 (27°56’08’’N, 15°30’10”W), MSS, 26 Dec. 2010, H. López leg. ( DZUL).

Total material

23 ♂♂, 17 ♀♀, 1 juv. (1 ♂, 1 ♀ analyzed).

Description

♂: L 11-21½ mm, H 0.82-1.00 mm, L/H 13-21, 31-53 podous rings + 1-4 apodous rings in front of telson. ♀: L 14-19 mm, H 0.95-1.08 mm, L/H 15-18, 42-47 podous rings + 1-2 apodous rings in front of telson.

COLOUR. The preserved specimens are uniform whitish yellow. Defence glands in part visible by transparency as dark spots.

HEAD. No eyes. 4 supralabral setae. Setae on gnathochilarial stipes: 3 apical, 5 (♂) / 0 (♀) nonapical. Length of antennae 162% of H in ♂, 123% of H in ♀.

BODY RINGS. Prozonites not furrowed. Metazonites unvaulted, with ca. 12 striae per dorsal quarter and a whorl of short setae on the posterior margin ( Fig. 2B ). Ozopore ¼ - ⅓ metazonite length behind suture. Limbus cells length slightly more than 2× width; their free margin with a few tiny denticles (as in Enghoff 1992: figs 28-29).

LEGS. Length 84% of H in ♂, 74% of H in ♀. Claw: length 7-8% of leg, length/height 4.4-5.4. Accessory claw 0.4-0.5× shorter than claw.

PREANAL RING. Without a projection, pilosity extensive.

Male

MANDIBULAR STIPITES. Without lobes.

LEGS. Second pair with ventral pads on postfemur and tibia. Postfemoral pads tiny, tibial pads small on midbody legs. Second pair with coxal pores.

GONOPODS. ( Figs 3C , 4C ) As in D. typhlocanaria sp. nov., except for the lack of a terminal projection on the mesal ridge of the anterior gonopod.

Female

RECEPTACULUM SEMINIS. A simple sack (as in Enghoff 1992: fig. 47).

Distribution and habitat

Endemic to Gran Canaria. Known only from the type locality in the NW part of the island, and from two further MSS sites in the East-Central part.

Figures

Fig. 2. A. D. typhlocanaria sp. nov., male from Cueva de la Luna, midbody rings. Scale 0.1 mm. B. D. oromii sp. nov., detail of posterior margin of midbody ring, showing diagnostic setae. Scale 0.05 mm.

Fig. 3. Anterior gonopods, posterior views. A. D. typhlocanaria sp. nov., specimen from Barranco Draguillo. B. D. typhlocanaria sp. nov., specimen from Cueva de la Luna. C. D. oromii sp. nov. D. D. typhlops Ceuca, 1973, specimen from La Palma, right anterior gonopod. ad: apical denticles, lp: lateral prominence, mr: mesal ridge, p: projection. Scales 0.1 mm (A-C), 0.01 mm (D).

Fig. 4. Posterior gonopods, mesal views. A. D. typhlocanaria sp. nov., specimen from Barranco Draguillo. B. D. typhlocanaria sp. nov., specimen from Cueva de la Luna. C. D. oromii sp. nov. ap: anterior process, pp: posterior process, mp: mesomerital process. Scales 0.1 mm.

Fig. 5. Size diagram for Dolichoiulus oromii sp. nov. and D. longunguis sp. nov. The diagram shows number of podous (leg-bearing) body rings (p.r., x axis) and vertical body diameter in mm (y axis). For a given number of podous rings D. oromii sp. nov. is thicker than D. longunguis sp. nov. but thinner than D. typhlocanaria sp. nov. (see Fig. 1); specimens of D. oromii sp. nov. from East-Central Gran Canaria are thicker than those from the Northwest (El Sao), and females are thicker than males.

Fig. 1. Size diagram for Dolichoiulus typhlocanaria sp. nov. The diagram shows number of podous (leg-bearing) body rings (p.r., x axis) and vertical body diameter in mm (y axis). For a given number of podous rings D. typhlocanaria sp. nov. is thicker than the two other species (see Fig. 5), and females are thicker than males.