Mymaromma menehune, Honsberger & Huber, 2022

Honsberger, David N., Huber, John T. & Wright, Mark G., 2022, A new Mymaromma sp. (Mymarommatoidea, Mymarommatidae) in Hawai'i and first host record for the superfamily, Journal of Hymenoptera Research 89, pp. 73-87 : 73

publication ID	https://dx.doi.org/10.3897/jhr.89.77931
publication LSID	lsid:zoobank.org:pub:DD914715-4804-4F7E-A4FF-196047B83756
persistent identifier	https://treatment.plazi.org/id/09DE5C66-46AC-4769-A296-E1A12C4F0C66
taxon LSID	lsid:zoobank.org:act:09DE5C66-46AC-4769-A296-E1A12C4F0C66
treatment provided by	Journal of Hymenoptera Research by Pensoft
scientific name	Mymaromma menehune, Honsberger & Huber
status	sp. nov.

Treatment

Mymaromma menehune, Honsberger & Huber sp. nov.

Figs 1B-D View Figure 1 , 2 View Figure 2 , 4 View Figure 4 , 7 View Figure 7

Material examined.

Holotype: female (Fig. 2A,B View Figure 2 ) (UHIM) uncleared in Hoyer’s medium sealed with epoxy, on slide with two labels as follows: "Hawaiian Islands, O‘ahu I., Mānoa, 21.2954°N, 157.8145°W, 15 m, 28.vi.2019, ex Ficus microcarpa branches, D. Honsberger ". " Mymaromma menehune Honsberger & Huber Holotype ♀ " GoogleMaps . Allotype: male (Fig. 2C,D View Figure 2 ) (UHIM) with same locality data as holotype. Paratypes: 12 females, 6 males, all except the two Moloka'i island specimens with same locality data as holotype except as indicated. Moloka‘i • Mapulehu Valley near Ili‘Ili‘opae heiau, 10-40', 8-22.xii.1995 and 12-26.iv.1996, W.D. Perreira, yellow sticky board traps (1♀ & 1♂ slide mounted, CNC). O‘ahu • 19.vi.2021, walking on Ficus microcarpa branches (1♀ slide mounted, UHIM) • 18.vi.2021, emerged from Lepidopsocus sp. eggs on Ficus microcarpa branches (1♂, UHIM, 1♀, BPBM, 1♂, CNC, all point mounted, each with host egg from which it emerged also glued to point) • 28.vi.2019 (1♀ & 1♂, BPBM, 1♀, CNC all slide mounted, 2♀ point mounted, CNC) • 17.v.2019 (1♀ slide mounted, BPBM, 1♀ point mounted, UHIM) • 27.vii.2018 (1♀, slide mounted, UHIM, 1♀ & 1♂ both slide mounted, CNC, 1♀ point mounted, 1♂ slide mounted, BPBM) GoogleMaps .

Other material examined.

1 female, 5 males, all slide mounted. Moloka‘i • Mapulehu Valley near Ili‘ili‘opae heiau, 10-40', viii.1995, 29.ix-13.x.1995, 1-15.iii.1996, W.D. Perreira, yellow sticky board traps (3♂, BPBM) • Hālawa Valley, 200', 29.ix-13.x.1995 and 27.x-10.xi.1995, J.W. Beardsley, W.D. Perreira, yellow sticky board traps (2♂, BPBM) • near Honomuni Str., 24.xi-8.xii.1995, W.D. Perreira, yellow sticky board traps (1♀, BPBM) .

Diagnosis.

Mymaromma menehune is most similar to M. goethei Girault, 1920 and M. longipterus Ayyamperrumal & Manickavasagam, 2017. All are distinguished from other described species of Mymaromma by the sculpture of the propodeum: obliquely striate in anterior half and transversely striate in posterior half (Figs 2F View Figure 2 , 4B,F,J View Figure 4 and as in fig. 79 - M. sp. 6 in Gibson et al. 2007) (propodeum with more or less isodiametric reticulations in most other described Mymaromma species).

Beardsley et al. (2000) and Gibson et al. (2007) had already noted that the Hawaiian specimens (not named at the time) were similar to M. goethei . Mymaromma menehune females differ slightly from M. goethei as follows: fu1 longer than fu2 and fu3 in M. menehune (Fig. 2B View Figure 2 ) (fu1 and fu3 subequal in M. goethei ); clava 3.5 × as long as wide in M. menehune (Fig. 2B View Figure 2 ) (clava 5.4 × as long as wide in M. goethei (CNC specimen)); mandible dorsal tooth rounded and subcircular, aburptly meeting at an approximate right angle the straight section that extends to the apex of the mandible in M. menehune (Fig. 2E,G View Figure 2 ) (dorsal tooth sharp and after its apex continues in a concave curve toward the base of the mandible in M. goethei (see Gibson et al. 2007, fig. 29)); meso/metapleural suture ventral to metapleural pit consistently deep throughout (Figs 1B View Figure 1 , 2D View Figure 2 ) (suture shallow ventrally below the metapleural pit in M. goethei ). Mymaromma menehune females are distinguished from M. longipterus by having: 6 funicular segments (Fig. 2B View Figure 2 ) (7 segments in M. longipterus ), with fu1 subequal to pedicel, fu5 and fu6, and longer than fu2 or fu3 (fu1 distinctly shorter than pedicel, fu2, fu3, fl5 and fl6 in M. longipterus ). Mymaromma menehune males have 10 flagellomeres with the apical 4 flagellomeres more widely joined together. Males are unknown for M. goethei and M. longipterus . A male from Thailand and two males from Taiwan that have the same propodeal sculpture as M. menehune and M. longipterus but differ in other features also have a 10-segmented flagellum. Males of M. goethei and M. longipterus must be discovered and correctly associated with conspecific females before any differences among males of the three species can be determined.

Description.

Female (Figs 1D View Figure 1 , 2A,B,E-G View Figure 2 , 3A,B View Figure 3 , 4E-G View Figure 4 , 7 View Figure 7 ). Body length of point mounted specimens 0.39-0.43 mm (n = 6), body length of slide mounted specimens 0.43-0.46 mm (n = 5), holotype 0.43 mm. Colour: Uniformly brown except for head ventral to eye yellow and small triangular patch ventral to tegula almost black; legs and petiole translucent yellow (Figs 2A-D View Figure 2 , 4A,B,E,F,I,J View Figure 4 ); tarsal segments 1-3 with apex dorsally dark brown, and segments 4 and 5 with apex dorsally light brown (Figs 2A,C,D View Figure 2 , 4A,B,E,F,I,J View Figure 4 ).

Head. Eye with about 35 ommatidia. Ocelli absent. Vertex, temple and gena faintly and finely transversely striate, with a few scattered white setae (Fig. 4 View Figure 4 ). Malar space short, about the length of one ommatidium. Antennae: Funicle 6-segmented (Fig. 2A,B View Figure 2 ). Length range/width range (ratio range) (n = 5) (Fig. 3A,B View Figure 3 ) of all segments: scape 36-51/11-12 (3.2-4.2), pedicel 24-29/15-16 (1.5-1.9), fu1 26-28/6-7 (4.0-4.8), fu2 19-22/6-7 (2.8-3.8), fu3 18-20/6-8 (2.4-3.1), fu4 23-25/7-9 (2.7-3.3), fu5 25-29/8-9 (3.0-3.2), fu6 27-30/10-13 (2.3-2.7), clava 98-108/26-31 (3.3-3.8). Mouthparts: Mandible tridentate (Fig. 2G View Figure 2 ); dorsal tooth rounded, its margin subcircular and abruptly meeting at an approximate right angle the straight projection forming the (mainly brown) apical tooth.

Mesosoma. Mesosoma length 2.22-2.42 × propodeum length (n = 5). Mesoscutum with raised isodiametric reticulate sculpture and four thick setae in a transverse line near posterior margin (Fig. 4B,F,J View Figure 4 ). Scutellum (Fig. 4B,F,J View Figure 4 ) with sculpture longitudinally striate anteriorly and laterally but isodiametric posteromedially and 1 lateral seta extending to anterior margin of frenum; frenum (Figs 2F View Figure 2 , 4B,F,J View Figure 4 ) with longitudinally striate sculpture. Pronotum laterally, propleuron and mesopleuron apparently with faint, fine, longitudinally striate sculpture at least in ventral half (Fig. 4A,E,I View Figure 4 ). Mesopleuron mostly smooth and shiny. Mesopleuron and metapleuron partially fused, in lateral view with suture between them consistently deep along its length and extending to metapleural pit at 0.74-0.76 × distance between sternum and propodeal spiracle (n = 5) (Figs 2B,D View Figure 2 , 4A,E,I View Figure 4 ). Metanotum in dorsal view as a narrow band about 10 × as wide as long, smooth (Figs 2F View Figure 2 , 4B,F,J View Figure 4 ) and apparently fused laterally with metapleuron. Propodeum (Figs 2F View Figure 2 , 4B,F,J View Figure 4 ) in dorsal view with Λ-shaped striations in about anterior third, these usually well-defined laterally (in some individuals becoming smooth near midline) and in posterior two thirds with transverse striations medially but curving posteriorly towards lateral margin, and in lateral view smooth; propodeum separated dorsally and laterally from metanotum by groove-like spiracular peritreme forming, in lateral view, acute angle with posterior margin of metanotum (Figs 2B,D View Figure 2 , 4A,E,I View Figure 4 ). Propodeal spiracle round to apostrophe shaped, somewhat like outline of a garden snail shell, with a single seta posterior to spiracle; propodeal flange ∩ shaped and evenly projecting, extending to bottom of petiolar insertion. Legs: Protarsal segments 3-5 subequal, with segment 1 slightly the longest and segment 2 very slightly the shortest. Meso- and metatarsal segments 2-5 subequal, with segment 1 slightly the longest. Wings: Fore wing with isodiametric reticulations, subhyaline and without infuscations (Figs 1C,D View Figure 1 , 2A,B,C,D View Figure 2 , 4B,E,I View Figure 4 ); fore wing length range/width range (ratio range) 354-385/85-96 (3.83-4.21); longest marginal (fringe) setae (1.74-1.88) × wing width. From basal seta on the posterior margin around the wing to anterior basal setae, the fringe setae as follows: 1 long basal seta inserted at wing margin; 6 or 7 shorter setae generally increasing in length distally and inserted at wing margin; about 38-41 (n = 5) long setae, the proximal 2 or 3 on both anterior and posterior margins inserted at wing margin, the remainder inserted well inside wing margin; about 11 short setae projecting from wing margin, the medial setae longer than the basal and apical setae, and 1 or 2 very short basal setae. Fore wing membrane with 2 long rows of microtrichia dorsally (Fig. 1C View Figure 1 -right wing, 1D-left wing) and 2 long rows and an additional, posterior short row of about 3 setae ventrally (Figs 1C View Figure 1 -left wing, 1D-right wing), generally as in Figs 1C,D View Figure 1 , 2A,C View Figure 2 but with exact placement varying slightly among individuals. Hind wing apically bifurcate, diverging into two rounded hooks with sharp ends smoothly bending back toward each other, leaving a subcircular opening between them.

Metasoma. Length range of P1/length range of P2 (ratio range) = 49-55/31-37 (1.42-1.58); P1 with small spicules ventrobasally, otherwise smooth; segment P2 slightly rougher especially ventrobasally. Cercus with four long setae. Ovipositor length 0.55-0.59 × metatibia length (n = 5).

Male (Figs 1B,C View Figure 1 , 2C,D View Figure 2 , 3C,D View Figure 3 , 4A-C,I-K View Figure 4 ). Body length of point mounted specimens 0.39-0.40 mm (n = 2), body length of slide mounted specimens 0.43-0.46 mm (n = 4), allotype 0.43 mm. Similar to female except as follows: profemur and protibia sometimes brown (Fig. 4K View Figure 4 ); antenna with 10 flagellar segments, forming a loose, indistinct clava with fl6-fl9 more widely united to each other, and wider and more globular than the consistently narrow (except fl6) basal segments and the smaller apical segment. Each segment with a whorl of long white setae (Fig. 4K View Figure 4 ) among other shorter ones. Antennal length range/width range (ratio range) (n = 4) (Fig. 3C,D View Figure 3 ): scape 39-46/9-11 (3.4-4.6), pedicel 24-28/14-15 (1.6-1.9), fl1 25-29/10 (2.6-3.0), fl2 27-32/9-10 (2.9-3.5), fl3 27-30/9-10 (2.9-3.1), fl4 30-32/9-10 (3.0-3.6), fl5 30-31/10-12 (2.6-3.2), fl6 27-29/12-14 (1.9-2.4), fl7 24/12-15 (1.6-1.9), fl8 23-27/14-18 (1.3-1.8), fl9 22-26/15-16 (1.4-1.6), fl10 24-28/10-11 (2.3-2.7). Mesosoma length 2.28-2.43 × propodeum length (n = 4). Fore wing length range/width range (ratio range) 342-395/89-97 (3.83-4.08); longest marginal (fringe) setae 1.83-1.98 × wing width (n = 4). Length range of P1/length range of P2 (ratio range) = 45-49/33-34 (1.36-1.46) (n = 4).

Etymology.

Because of its size and elusivity, this species is named after the Menehune, in Hawaiian legend a people who were small and not often seen, that live in the forests and are known for being industrious craftspeople who emerge during the night and build structures.

Host record and parasitoid behavior.

Three M. menehune individuals emerged from the eggs in the capsules, all from morphologically identical eggs, and each M. menehune individual from a single egg in a single capsule (Fig. 4 View Figure 4 ). These eggs were confirmed through rearing of additional identical eggs to be of a Lepidopsocus sp. ( Psocodea : Lepidopsocidae ) (Fig. 5 View Figure 5 ). Eggs of this species on the branches inspected were observed to be placed singly, typically in the trough of a shallow topographical feature on the wood surface, such as a small fissure or recess in the bark, the crevice chewed for egg placement by an ovipositing cerambycid, or the crevice created by bark separating from the xylem on a broken branch (Fig. 5 View Figure 5 ). We are confident that the eggs reared for identification and the eggs from which M. menehune emerged belong to the same species. A previous study of arthropods emerging from similar branches taken from the same tree over the course of approximately one year (D. Honsberger, unpublished) yielded four species of bark lice from the wood: Lepidopsocus sp., Ectopsocus? spilotus and Ectopsocus? pilosus , and a Psocidae sp. There is great variation in egg morphology within Psocodea . Ectopsocus? pilosus and the Psocidae sp. were found through rearing of other eggs collected on the wood to have morphologically dissimilar eggs to those of the Lepidopsocus sp. (Fig. 6 View Figure 6 ), and eggs of E.? spilotus could be assumed to be similar to those of the congeneric E.? pilosus and dissimilar to Lepidopsocus sp. eggs ( New 1987). The host-parasitoid association was thus confirmed.

Three mymarommatoids were observed on the surface of the branches inspected under the microscope (Fig. 7 View Figure 7 ; Video 1 https://vimeo.com/666102893). They were subsequently identified as the same species that emerged from the eggs and is described above. The wasps were observed to walk rapidly over the bark surface and groom themselves frequently. No encounter with host eggs was observed. The position of the bellows on the head while the wasps were exploring the wood may be of note, as it has not previously been reported in living individuals. The occiput was flush with the vertex, and expansion or movement of the bellows was not observed. This lack of utilization of the bellows while searching on wood is consistent with its possible function proposed by Huber et al. (2008) where, in combination with the exodont mandibles, the bellows is expanded to assist in bursting out of a host egg with a flexible chorion.