Symphylella erecta, Camacho & Vandenspiegel, 2012

Camacho, Miguel Domínguez & Vandenspiegel, Didier, 2012, Scolopendrellidae (Myriapoda, Symphyla) from the Afrotropics with descriptions of seven new species, European Journal of Taxonomy 32, pp. 1-28 : 4-6

Symphylella erecta sp. nov.

urn:lsid:zoobank.org:act:BA6D2348-A8FE-4CF9-A9DB-643B55E53E78

Figs 1 , 7A

Type material

Holotype

1, sex unknown, CONGO D. R., A. N. P., Secteur Sud , riv. Fuko, affl. Dr. Rutshuru, 1300 m, coll. De Witte, 12 Nov. 1954 ( MRAC 22148 ).

Paratypes

1, sex unknown, same data as holotype ( MRAC 22149); 1, sex unknown, CONGO D. R., A. N. P., Secteur Sud, riv. Rumanura, affl. Fuko, 1200 m, coll. De Witte, 3 Dec. 1954 ( MRAC 22150).

Type locality

CONGO D. R., A. N. P., Secteur Sud, riv. Fuko, affl. Dr. Rutshuru, 1300 m.

Other material

1, sex?, TANZANIA, Mt. Uluguru, Kinola, forêt transit, Berger, Leleup, Debecker ( MRAC 22163), which probably belongs to this species, although it was not directly observed by SEM.

Etymology

From the Latin erectus = upright, referring to the long and erect setae on the tergites.

Description (holotype)

LENGTH. 2.3 mm.

HEAD. 1.1 times as long as broad with broadest part behind the middle on a level with the points of lateral protuberances ( Fig. 1A ). Lateral margins nearly straight. Central rod faint, most distinct in posterior half ( Fig. 1A ). Frontal branches also faint. Median branches absent. Dorsal surface with setae of different lengths. Cuticle with faint and dense pubescence ( Fig. 1B ).

ANTENNAE. Left antenna 16 segments, right 14 ( Fig. 1G ). First segment smallest, following segments about 1.2 times as wide as long. Total number of setae visible in dorsal view: 3 on first segment and 4 on second and third ones. Longest setae of proximal segments about 2.3 times as long as those of distal segments. Average length of setae about 0.3 diameter of the basal segments. One whorl of setae on proximal segments, secondary whorl begins on ventral side of 7 th or 8 th segment. Apical segment globular with several short distal setae. All segments with faint pubescence.

TERGITES ( Figs 1A, 1E , 7A ). First tergite rudimentary with eight setae arranged in two groups of four. Second tergite complete; triangular posterior processes with straight margins and glabrous tips, no endswelling ( Fig. 1A, E ). Margin between projections straight. One marginal seta between apical and inner basal setae. Inner basal setae thick, erect and long, as long as anterolateral seta. Eight posteromarginal setae – apical ones included –, two setae in the medial position – central setae. Five lateromarginal setae on each side, –anterolateral setae included – some of them larger and very erect, alternating with the smaller ones. Anterolateral setae very prominent in all tergites except most posteriors, erect, pointing forwards and protruding from both sides. Second tergite with one anterolateral seta on each side, 3rd and following ones with two. Third tergite with six posteromarginal setae and eight lateromarginal on the right side, four visible on the left side – anterolateral setae included – some larger and very erect, alternating with smaller ones. All tergites with faint pubescence.

LEGS. First pair of legs not visible in holotype, strongly reduced to small spiny spot with two protruding setae each in paratypes ( Fig. 1C, D ). Last pair of legs with few and small setae. ( Fig. 1H ). Tarsus with a few distinct small setae in distal part and two longer and erect setae on dorsal side ( Fig 1H, I ). Cuticle with very faint pubescence.

STYLI. Not visible in holotype, short and subglobular, with short thick hairs in paratypes ( Fig. 1F ).

CERCI. 3.2 times as long as wide, slightly curved laterally ( Fig. 1I ). 35-40 setae in dorsal view on each cercus. Setae either short, slightly curved, depressed, clothing all sides, or long straight erect, inserted on outer and ventral sides. Distal half of outer side with 1 or 2 long and erect setae; ventral side with 4-6 erect setae arranged in a longitudinal row ( Fig. 1H ). Cuticle with faint pubescence. Terminal area conical, 0.1 times of the length of cerci, six-nine transversal striae. Apical seta curved inwards, about as long as terminal area.

Affinities and differential diagnosis

Symphylella erecta is very similar to S. simplex ( Hansen, 1903) and S. multisetosa Scheller, 1971 from South Asia. These species differ from all other Symphylella species in the combination of having 8 setae on the first tergite, setae between the apical and inner basal setae of the triangular processes, some of the lateromarginal setae on the second tergite erect and the presence of at least one row of erected setae in the ventral part of the cerci. However, S. erecta is distinguished by the presence of long inner basal setae on the triangular processes of the second tergite, as long as the largest lateromarginal one, strongly reduced first pair of legs and the presence of frontal branches in the head. The presence of the subglobular styli is also a diagnostic feature of this species.

Figures

Fig. 1. Symphylella erecta sp. nov., holotype (dorsal and lateral views) and paratype MRAC 22149 (ventral view). A. Head and first 4 tergites (T1, T2, T3, T4), dorsal view. Cr, central rod; fb, frontal branches; lp, lateral protuberances of head. B. Detail of the surface of head. C. Detail of first leg. D. Head and first 2 pairs of legs, ventral view. E. Detail of first (T1) and second tergites (T2). Al, anterolateral setae; as, apical setae; cs, central setae of the posteromarginal setae; ibs, inner basal setae of the posteromarginal setae. F. Stylus of leg 10. G. Right antenna. H. Posterior part of trunk, last pair of legs (t, tarsus) and cerci (C), lateral view. Arrows: erect setae of tarsus, es, ventral erect setae of cercus. I. Posterior part of trunk, last left leg and cerci (C), dorsal view. Arrows: two erect setae of tarsus (t) of the last left leg; as, apical seta; es, erect setae of the outer side of the cerci; ta, terminal area.

Fig. 7. Schemata of the three first tergites and chaetotaxy of the described species of Symphylella. A. S. erecta sp. nov. B. S. fuko sp. nov. C. S. kalundu sp. nov. D. S. lubumbashi sp. nov. E. S. malagassa sp. nov. F. S. tanganyika sp. nov. — Marginal setae of second and third tergites labelled: lm, lateromarginal setae; lm (al), anterolateral seta of lateromarginal; p, posteromarginal setae; p(a), apical setae – belonging to the posteromarginal setae; p(c), central setae of posteromarginal; p(ib), inner basal setae of posteromarginal; s, seta between first and second tergites. Scale: 50 μm.