Leioproctus (Goniocolletes) wanni (LEIJS AND HOGENDOORN)

Rozen, Jerome G. & Houston, Terry F., 2022, Descriptions of the Mature Larvae of Three Australian Ground-Nesting Bees (Hymenoptera: Colletidae: Diphaglossinae and Neopasiphaeinae), American Museum Novitates 2022 (3989), pp. 1-16 : 3-5

Leioproctus (Goniocolletes) wanni (LEIJS AND HOGENDOORN)

Figures 1A, B – 3

DIAGNOSIS: The larva of Leioproctus wanni is similar to those of the four neopasiphaeine species described by McGinley (1981) in not spinning a cocoon; labium recessed in lateral view; salivary opening (fig. 6) small, at most only slightly protruding and oval but capable of closing as dorsal edge curves downward; labral tubercles small. Distinguished from those same four species in frons being broadly depressed between mounds mesad of parietal bands, antennal mounds and projecting clypeus.

The following description of the larva of L. wanni is based on four specimens, all postdefecating.

HEAD: Unusually small compared with body size (fig. 1B) as seems to be characteristic of most larval Colletidae illustrated by McGinley (1981). 3 Integument thick, faintly translucent amber where not pigmented, with outer surface strongly, minutely wrinkled, thereby providing rigidity to surface of head capsule. On cleared head capsule, posterior thickening of capsule narrow but distinct, pleurostomal and epistomal ridges evident; median coronal ridge not evident; parietal bands distinctly impressed (figs. 2, 4); integument mesad of each band produced as a mound (figs. 2–5) below each of which occurs large antennal mound (figs. 2–5); epistomal ridge in frontal view (figs. 2, 4) curving slightly upward between anterior tentorial pits but remaining well below level of antennae; anterior surface of clypeus sharply bending forward from epistomal ridge in lateral view (figs. 3, 5), hence front of face in frontal view (fig. 4) of mature larva dominated by large depression created by mounds mesad of parietal bands and antennal mounds and above projecting clypeus. Labrum small, bearing pair of moderately small apical tubercles (fig. 3). Mandibular apex sharply pointed, pigmented, rather short but broadening quickly approaching broad inner surface of cusp; apical dorsal edge with numerous fine teeth; ventral apical edge well defined but without teeth at extreme apex; broad cuspal area surface densely covered with fine, darkly pigmented denticles. Maxillae (fig. 5) moderately large, each with tapering elongate palpus that is pigmented. Labium recessed, short in lateral view (fig. 3) with scarcely projecting, unpigmented palpi. Salivary opening (fig. 6) small, at

3 Although McGinley (1981) referred to the heads of some colletid larvae as moderate in size, now—40 years later—they are more accurately described as small headed relative to body size, based on our current, more inclusive understanding of head-size range among a larger sampling of mature bee larvae.

most only slightly protruding and oval, but capable of closing as dorsal edge curves downward, all as in Trichocolletes orientalis .

BODY: In lateral views of mature larva (figs. 1B, 7), body segments 1–4+5 increasing in size posteriorly, and segments posterior to segment 5 gradually, evenly tapering in size toward posterior end; terminal segment as illustrated (fig. 1B). Most body segments clearly divided dorsally into anterior and posterior annulets. Each posterior annulet with dorsolateral transverse linear series of low rounded projections on each side that diminish laterally well before reaching level of spiracles; linear series of projections on body segments interrupted along body midline; specimen cleared and treated with ethanol solution of Chlorazol Black E with paired ridges scarcely staining. Spiracular peritremes, though not tuberculate, projecting somewhat from body surface (figs. 7, 8); see Discussion below.

MATERIAL EXAMINED: Four postdefecating larvae: Leiopr. (Goniocolletes) wanni . Corackerup Creek, c. 44 km SSW of Jerramungup, W.A. 34.2932° S, 118.6998° E, 26 September 2019, T. F. Houston 1567-1 .

DISCUSSION: One of us (T.F.H., 2020a) provided both a detailed description of the nesting site and nests with more or less horizontal cells from which larval specimens of Leioproctus wanni were gathered. Mature larvae were clearly not enclosed in cocoons.

The two mounds each mesad of the parietal bands of this species (figs. 2, 3) are unusual features but somewhat similar mounds occur in Xeromelissinae sp. A ( McGinley, 1981: figs. 80, 81).

Spiracles of postdefecating larvae are small and questionably understood. The atrium is darkly pigmented, very possibly but not certainly spiculate as in T. orientalis , described below, but the apparent spiculation on the single specimen cleared for study may also have been an artifact of fine particle contamination.

Figures

FIGURE 1. A. Enlarged diagram of head of mature larva of Leioproctus wanni, frontal view, identifying major anatomical features of head capsules of bee larvae. B. Diagrams of mature larva of Leioproctus wanni. Fullbody lateral view. Scale bar = 2 cm.

FIGURES 2, 3. Diagrams of mature larva of Leioproctus wanni. Head, frontal and lateral views. Scale bar = 2 cm.