Lamproclasiopa fumipennis (Wirth)

Costa, Daniel N. R., Mathis, Wayne N. & Marinoni, Luciane, 2016, A revision of the shore-fly genus Lamproclasiopa Hendel (Diptera, Ephydridae), ZooKeys 631, pp. 1-99 : 85-87

Taxon classification Animalia Diptera Ephydridae

Lamproclasiopa fumipennis (Wirth) Figs 132, 139

Discocerina (Basila) fumipennis Wirth 1955: 53; 1968: 7 [Neotropical catalog]. Mathis and Zatwarnicki 1995: 165 [world catalog].

Lamproclasiopa fumipennis . Zatwarnicki and Mathis 2001: 39 [generic combination].

Diagnosis

(based on Wirth’s original description). This species is distinguished from other congeners by the following combination of characters: Moderately small shore flies, body length about 3.00 mm; generally subshiny, blackish; sides of body with more or less dull brown microtomentum. Head: 1.2 × broader than high. Frons 1.4 × as broad as long; frons and occiput densely brown microtomentose; 1 pair of proclinate and 1 pair of reclinate fronto-orbitals, ocellar setae more widely separated than posterior ocelli, situated at a level about midway between bases of fronto-orbitals and anterior ocellus; pseudopostocellar setae 1/2 length of ocellar setae; medial and lateral vertical seta well developed. Basal flagellomere and palpus yellowish brown; arista with 5 dorsal rays. Face, parafacials, and gena gray, microtomentose; 2 pairs of strong facial setae; a row of very fine setulae at each parafacial suture; parafacial narrow, bare. Thorax: Mesonotal and discal setulae numerous and unordered; notopleuron and anepisternum with sparse setulae. A pair of strong humeral setae; notopleural setae strong, both pairs located near notopleural suture, anterior pair slightly closer to posterior pair than to humeral setae; presutural setae, supra-alar setae and prescutellar setae well developed; a somewhat weaker pair of postalar setae; lateral and apical pairs of scutellar setae each about as long as prescutellar setae. Wing densely brown infuscate (Fig. 132), veins blackish; costal section II 2.2 × as long as section III; apex of vein R3+4 not noticeably curved into costa. Halter with yellow knob. Knees narrowly pale brownish; basal 2 tarsomeres yellowish, apical 3 brown; setae and setulae of legs and abdomen rather strong; no flexor armature on femora. Abdomen: Tergites more sparsely microtomentose than mesonotum, shinier black or brown, especially laterally and mostly of tergites 4 and 5. Male terminalia: Epandrium in posterior view generally oval, higher than wide, dorsal portion thin, gradually becoming wider ventrally, widest subapically, apex tapered, rounded pointed, apex and dorsal half bearing more setulae, in lateral view with dorsal half almost parallel sided, ventral portion expanded, with rounded ventral margin and shallow, anterior point subapically; cerci in posterior view elongate, thin, ventral half tapered to acute point, slightly curved, setulose on dorsal half, in lateral view elongate, thin, dorsal half wider than ventral portion, tapered toward ventral apex; in about as wide as long, narrower dorsally and ventrally, widest at midheight, each lateral arm widest ventrally, ventral margin mostly evenly rounded, with a shallow medioventral extension, more or less evenly setulose along length; cercus narrowly hemispherical, slightly curved, gradually tapered toward ventral apex; gonite in lateral view rod-like, shallowly arched, apices tapered, with broad, short process beyond midlength, in ventral view irregularly V-shaped, arm toward aedeagal base much longer, tapered, more basal arm short, digitiform; aedeagus in lateral view narrowly funnel-like, wider basally, apical half tapered to narrow, parallel-sided extension, in ventral view elongate, thin, tapered very gradually from base to apex, narrow apex rounded, base arched; phallapodeme in lateral view L shaped, each arm tapered to narrowed apex, keel at angle, slightly extended, in ventral view narrowly spindle shaped, apices expanded, end toward hypandrium bifurcate; hypandrium in lateral view rod-like, shallowly arched, in ventral view with anterior half robustly developed, more or less quadrate, anterolateral corners rounded, anterior margin shallowly emarginated, posterior extensions elongate, tapered, posterior margin deeply emarginate, V-shaped.

Type material.

The holotype female of Discocerina (Basila) fumipennis Wirth is labeled "Chile. Juan Fernández Islands, Masatierra, Plazoleta del Yunque (33°38.8'S, 78°50.1'W); HT ♀, UMCE]." Holotype female, allotype male, Masatierra, Plazoleta del Yunque, 200 meters, 9 January 1952, (in dense forest).

Other specimens examined.

CHILE. Valparaíso: Juan Fernández Islands, Robinson Crusoe Island (Plazoleta, trail sweep; 33°38.8'S, 78°50.3'W), 1-8 Jan 1993, S. A. Marshall (17♂, 2♀; DEBU, USNM); (quebrada S side Mirador, fern forest, 20 pans; 33°38.7'S, 78°51.1'W), 1-10 Jan 1993, S. A. Marshall (1♂; DEBU); (El Yunque Trail; 33°39'S, 78°50.6'W), 9 Jan 1993, S. A. Marshall (4♂; USNM); (English Bay; 33°37.2'S 78°50.9'W), 5 Jan 1993, S. A. Marshall (1♂, 1♀; DEBU).

Type locality.

Chile. Valparaíso: Juan Fernández Islands, Masatierra, Plazoleta del Yunque (33°38.8'S, 78°50.1'W; 200 m; dense forest).

Distribution

(Fig. 139). Neotropical: Chile ( Valparaíso: Juan Fernández Islands.)

Remarks.

Our diagnosis of this species is partially based on Wirth’s original description (1955), as we have not been given access to the holotype, which is a female, or to the male paratype, which Wirth designated as the allotype.

When Wirth (1955) described this species, he wrote the following as a comparative diagnosis. This species is (p. 54) "Most closely related to Discocerina (Basila) puella (Cresson) from Chile, but that species has the wings hyaline, the body much duller, microtomentose above and the tarsi entirely yellow. Discocerina (Basila) polita (Edwards) from Chile is a polished, metallic black species with hyaline wings."

We concur with Wirth that this species is indeed closely related to Lamproclasiopa puella and suggest, further, that these two “species” may be conspecific. Externally there are some differences, as Wirth noted and as we have confirmed herein (see key and respective diagnoses). Moreover, we have observed that these external differences, although slight, are consistent. The populations are separable. The shapes of structures of the male terminalia, however, are essentially the same for Lamproclasiopa puella and the darkened specimens from the Juan Fernández Islands. Thus, while we have observed that a level of genetic diversification has occurred in the island populations, the question of whether it is sufficient to represent speciation remains an open question-the dilemma of diversified, allopatric populations. For the present, we are continuing to recognize the populations from the islands as a separate species, especially as we have not been able to study the type series.

Our records indicate that this is the only congener known to occur on the Juan Fernández Islands.