Eumastigonus kaorinus Chamberlin, 1920

Korsós, Zoltán & Johns, Peter M., 2009, Introduction to the taxonomy of Iulomorphidae of New Zealand, with descriptions of two new species of Eumastigonus Chamberlin, 1920 (Diplopoda: Spirostreptida: Epinannolenidea), Zootaxa 2065, pp. 1-24 : 8-10

Eumastigonus kaorinus Chamberlin, 1920

Figs. 4 –15, 22.

Eumastigonus kaorinus Chamberlin, 1920: 162 . Hoffman 1972: 200.

Types: Holotype 3 (MCZ 4867), paratype Ƥ (MCZ 4868). – New Zealand, near Swainson (= Swanson, Auckland, North Island), kaori (= kauri) forest, leg. W. M. Wheeler 1914 (labelled as Eumastigonus wheeleri ).

Other material studied: 433, 35Ƥ, and 4 juvs

New locality records: Northland Region: Mangamuku Gorge, picnic area, 85 m, leg. F. M. Climo, 1 May 1968, 23, 2Ƥ ( CMNZ). Russell, Ngaiotonga Scenic Reserve, leg. PMJ, 18 Dec. 1963, logs, 13, 1Ƥ ( CMNZ). Maungaturoto, leg. PMJ, 3 Dec. 1963, in taraire-kohekohe broadleaf forest, 13 ( CMNZ). Utakura, Mataki, 269 m, leg. PMJ, 19-26 Feb. 2006, nikau fronds, 13, 1Ƥ ( CMNZ) and kanuka, 13, 1 juv. ( CMNZ). Waipoua, Trounson Kauri Park, 240 m, leg. PMJ, 3-4 Dec. 1963, logs, 23 ( CMNZ). Whangaruru, head of peninsula, leg. F. M. Climo, 28 Apr. 1968, 23, 4Ƥ ( HNHM, vulva removed for drawing) and 28 May 1968, 13, 4Ƥ ( CMNZ).

Auckland Region: Waiwera, leg. PMJ, 3 Dec. 1963, pohutukawa-taraire forest, 43, 3Ƥ, 1 juv. ( CMNZ). Warkworth, Kowhai Park, leg. PMJ, 22 Oct. 1999, under logs and stones, 53, 1Ƥ ( CMNZ). „Ahureka”, Whitford–Maraetai road, leg. P. M. Johns ( PMJ), 5 Nov. 1995, under logs and stones in Dysoxylum , 13 ( CMNZ). Pollok, 90 m, leg. PM & M. Johns, 7 Jan. 1964, pohutukawa-taraire forest, 13, 2Ƥ ( CMNZ). Waiuku, Bush reserve, Kemps Road, 80 m, leg. PM & M. Johns, 7 Jan. 1964, 123, 8Ƥ, 2 juvs ( CMNZ: 1 male dissected for SEM: anterior and posterior gonopods). Waitakere Mt Range, Piha Gorge, leg. PM & M. Johns, 11 Jan. 1964, in regenerated kauri forest, 23, 2Ƥ ( CMNZ: one male is dissected for SEM: head, 1st legpair, 2nd legpair with penis, gonopods, 7th ring).

Bay of Plenty Region: Rotorua, Toruhepe Scenic Reserve, 540 m, leg. PMJ, 20 Dec. 1973, ferns etc, 63, 7Ƥ ( CMNZ).

Redescription based on type and recent material: Length: 32–41 mm, max. midbody diameter: 1.8–2.3 mm, no. of rings: 39–59 (holotype 3 with 50+1+telson, paratype Ƥ 47+2+telson).

Head as in Fig. 5 , mandibular lobe deep, produced anteriorly, its margin broad, thin, mesal face not swollen; ocellarium broad, elongate oval or subtrapezoidal in outline, approx. 30–35 ocelli in 4–5 rows (in paratype female 5+8+9+9), smallest ocelli along anterior edge. Antennae short, antennomeres 2–6 subequal in length, 1–3 glabrous, 4th weakly, 5–7 densely setose, apically with four sensory papillae. Collum subtriangular, glabrous, posterior margin with incomplete furrow, lateral corner on both sides with 3–4 slightly bent furrows.

FIGURES 10–15. E. kaorinus male from Waitakere Range, Auckland Region, scanning electronmicrographs. 10: Gnathochilarium, ventral view, 11: posterior gonopods, anterior view (sg = seminal groove), 12: 7th ring, right lateral view, 13: first legpair, posterior view, 14: anterior gonopods, anterior view (c = coxa), 15: anterior gonopods, posterior view (tp = telopodite process, t = remnant of second telopodomere).

Body rings with 8–12 fine striae on metazonae only on the lower third part of the area below ozopores. Ozopores weak, closely behind suture. Telson blunt, glabrous, paraprocts rounded, with 2+2 marginal setae (cf. Fig. 48).

Colouration: Almost uniformly dark brown, the posterior edge of each ring slightly paler; head with dark vertex, pale front and sides; collum with submarginal dark band, more extensive laterally; telson dark with pale margin, anal valves dark; legs light brown.

Male sexual characters: 1st legpair short, without (rarely with) claws ( Figs. 6 and 13); legs 2–6 unmodified; legs of ring 8 onwards with small prefemoral pads, decreasing in size caudally. Penis closely behind 2nd legpair, clearly divided into two branches, apical parts are long and attenuated.

Protrusion on 7th ring (Fig. 12) well-developed, protecting slightly emerging gonopods.

Gonopods, illustrated here for the first time ( Figs. 7–9 , 11, 14–15), heavily built, anterior gonopod coxae (c) basally broad, in anterior view rectangular, on their posterior surfaces mediobasally with a small field of setae (here considered as remnant of telopodite, t on Fig. 15), coxal processes distally with a strong lateral constriction, then widening again, almost to the same width as their bases, forming on each side a subtriangular, pectinate shoulder and a long, blunt inner process. Medial lobe of anterior gonopod (m) thin, membraneous, not reaching tip of inner process, posterior lobe (=telopodite process, tp) strong again, apical margin densely setose. Posterior gonopod slender, cylindrical, coxa with longitudinal lamina sheathing flagellum in situ, the lower inner part of its margin caudally crenulate. Posterior gonopod apically clearly articulated, tip of coxa round, obtuse, setose, telopodite slim, its length about one-sixth of entire posterior gonopod, apex (a) pointed, subapically a spoonlike, rounded depression. Seminal groove (sg) runs along anterior surface, starting on the inner side, first concealed by the lamina then reaching the setose top of coxa and going into the pointed telopodite.

Females vulvae ( Fig. 22 ): Bursa compact, valves compressed against each other, their tips slightly pointed, anterior and posterior valves marginally with 3 and 1 setae, respectively. Operculum (o) small, pointed, hidden behind bursa. Inner structure not observed.

Distribution: New Zealand, North Island, Auckland and Northland Regions. See Fig. 52 .

Remarks: Hoffman (1972) could not find the type of E. kaorinus in the MCZ, because it was labelled as E. wheeleri (although Hoffman surmised it, implying that Chamberlin could have changed the name without changing the original label). We found E. wheeleri in the MCZ under Nos 4867 and 4868, which proved to be the types of E. kaorinus and herewith selected these specimens as types of E. kaorinus .

Figures

FIGURE 52. New Zealand, North Island, distributions of E. kaorinus (infilled squares), E. distinctior (blank squares), and E. hemmingseni (infilled triangles).

FIGURES 4 – 9. Eumastigonus kaorinus. 4: Gnathochilarium of paratype female (MCZ 4868), ventral view, 5: head of holotype male (MCZ 4867), left lateral view, 6: first male legpair, posterior view, 7: anterior gonopods, anterior view (c = coxa, m = median lobe), 8: right gonopods, right lateral view, posterior gonopod removed from embrace of anterior ones, flagellum omitted (tp = telopodite process), 9: posterior gonopods, posterior view (a = apex). Scales 4 – 5: 1 mm, 6 – 9: 0.5 mm.

FIGURES 22 – 24. Female vulvae (op = operculum). 22: E. kaorinus from Whangaruru headland, Northland Region, right vulva, anterior view, 23: E. distinctior from Porirua, Wellington Region, Galathea Expedition, 1951 (ZMUC), left vulva, posterior view, 24: E. hemmingseni from Akatarawa, Wellington Region, right vulva, posterior view. Scales 0.5 mm.