Hemiblabera brunneri (Saussure)

Lu, Wenhua, Valentine, Barry D., Perez-Gelabert, Daniel E. & Gutiérrez, Esteban, 2014, Ecology and Diversity of Cockroaches (Dictyoptera: Blattaria) from the Virgin Islands, Insecta Mundi 2014 (349), pp. 1-32 : 7-9

2. Hemiblabera brunneri (Saussure) ( Fig. 5 )

Blabera brunneri Saussure 1869: 113 ; Brazil. Diagnosis. Brachypterous adults 21–37 mm, oval, with quadrate tegmina in both sexes; dorsum shiny, dark brown, with prominent yellowish pronotal margin reaching basal angles; head dark with 2 small, pale spots (ocelli) between antennal insertions and a larger reddish area on frons above clypeus; pronotum broader than long; tegmina unicolor or faintly paler laterally, with small punctures and vague wrinkles, without transverse discal grooves; anteroventral margin of fore femur with a row of stout proximal spines, followed by a row of short uniform spinules, and one larger terminal spine (Type B 1); supra-anal plate rectangular, with rounded angles and slight apical emargination in both sexes; tarsi almost black, variably 4 or 5 hind tarsomeres; abdominal segments dark red anteriorly, dark brown posteriorly; cerci short, flat, and rounded at tip.

Wingless adults and nymphs are very unlike the brachypterous adults; yellow pronotal margin narrow, dull, sometimes extending to meso- and metanotal margins; pronotum dull and rough with many small, flattened tubercles, which are progressively smaller and more acute on the rest of dorsum; head dark but genae and frons sometimes lighter, abdominal tergites transversely banded with light and dark brown, sometimes with a vague yellowish spot on each side. There are 10 instars based on anterior pronotal width corresponding to head width categories of 1.5, 3.0, 3.5, 4.0, 5.5, 6.0, 7.5, 9–10, 11.0–12.0, and 12.5–13.0 mm. We could not sex instars 1–3; the sex ratio of male and female adults and older nymphs is about 1:1. In addition, the posterior lateral margin of tegmina is longer than the sutural margin in females compared to males.

Comments. Hemiblabera brunneri is ovoviparous; a 27 mm female collected on Guana on 22 October 2004 gave live birth to 17 nymphs overnight, each about 7 mm long. It is a dimorphic species with both brachypterous and wingless adults. We found all sizes of individuals except the brachypterous form under rocks on Carval Rock, a very small island between Cooper and Ginger Islands with only herb-stage vegetation except for a few Coccoloba uvifera L. ( Polygonaceae ) shrubs ( Lazell 2005), suggesting that it reproduces without winged adults. Furthermore, many wingless individuals are larger than brachypterous males. In early October 2008, nymphs and more than 20 both brachypterous and wingless adults were found coexisting in daytime under a coral rock in a low, sandy, wooded area next to the White Bay beach on Guana Island; that night they all disappeared, but many were found under the same rock the next day. This suggests it may be aggregative socially or nuptially. In daylight when disturbed, most dove into the sand and “swam” away. It is nocturnal and usually stays close to the ground, but was once found on branches> 2 m above the ground. It can be found abundantly in suitable habitats on Guana Island ( Table 1), from almost sea level to near the highest point.

Shelford (1910) first recorded this species from St. Thomas, Roth (1994) from Virgin Gorda, and Lazell (2005) from Guana Island; it is herein recorded for the first time on Anegada, Carval Rock, Little Thatch, Moskito, Necker, Norman, Prickly Pear, Salt, and Tortola of BVI, in addition to other previous records on St. John and St. Thomas of USVI, Culebra Island, Puerto Rico, and St. Vincent ( Rehn and Hebard 1927, Princis 1963, Gutiérrez and Fisk 1998).

Specimens examined. BDVC — 1 male, BVI, Anegada Is. , airport vicinity, 22.X.2004, Valentines & Sibleys ; 2 females / 1 male, BVI, Anegada Is. , SW coast, 20-21.X.2004, Valentines & Sibleys, at UV ; 1 female, BVI, Guana Is., Grand Ghut , 13.X.2006, B. D. Valentine family, sweep ; 2 females, BVI, Guana Is. , 22-28.X.2001, 23-30.X.2002, B. & B. Valentine, at UV ; 1 female / 2 males, BVI, Guana Is., White Beach , 15.X.2007, W. Lu ; 1 female /17 hatchlings, BVI, Guana Is., 22.X.2004, B. D. Valentine & S. C. Valentine- Cooper ; 1 male, BVI, Guana Is. , 22.X.2007, B. D. Valentine family ; 2 females, BVI, Little Thatch Is. , 25.X.2008, Valentine-Cooper & Lu ; 3 adults, BVI, Little Thatch Is. , 11.X.2010, E. Wright ; 1 male, BVI, Moskito Is. , 25.X.2007, W. Lu, sweep ; 1 male / 2 females, BVI, Moskito Is. , 23.X.2008, Valentine-Cooper & Lu ; 1 male / 1 female, BVI, Moskito Is., 26.X.2009, W. Lu & S. Valentine-Cooper ; 1 male, BVI, Prickly Pear Is. , 23.X.2011, [K. Street, in Agave ] ; 1 female, BVI, Necker Is. , 2-5. VI.2005, W. Lu ; 1 female, BVI, Norman Is., 25.X.2002, T. Willard ; 1 female / 1 male, BVI, Salt Is., 12.X.2007, W. Lu, sweep ; 1 female, BVI, Virgin Gorda Is. , Oil Nut Bay , 12.X.2008, [B. S. Barker, mango tree litter]. NMNH — 1 female, BVI, Tortola, Sopers Hole, 31. III.1958, J.F.G. Clarke. Wingless adults and nymphs examined: BDVC — 3 male / 1 female nymphs, BVI, Anegada Is., airport vicinity, 22.X.2004, Valentines & Sibleys ; 1 female /9 nymphs, BVI, Carval Rock Is. , between Cooper & Ginger Is., 6.X.1999, W. Lu ; 1 female nymph, BVI, Guana Is. , 8-14.X.2001, B. & B. Valentine ; 1 female nymph, BVI, Guana Is. , 14.X.2007, W. Lu, sweep ; 1 female nymph, BVI, Guana Is. , 21.X.2007, B. D. Valentine family ; 1 nymph, BVI, Guana Is. , 24.IX.2005, B. D. Valentine & S. C. Valentine-Cooper ; 3 male nymphs, BVI, Little Thatch Is. , 18.X.2004, S. C. Valentine-Cooper, at light ; 3 females /2 nymphs, BVI, Little Thatch Is. , 25.X.2008, Valentine-Cooper & Lu ; 1 male /1 nymph, BVI, Moskito Is. , 23.X.2008, Valentine-Cooper & Lu ; 2 nymphs, BVI, Moskito Is. , 26.X.2009, W. Lu & S. Valentine-Cooper ; 1 female, BVI, Virgin Gorda Is. , Oil Nut Bay, 12.X.2008, [B. S. Barker, mango tree litter]. MCZ —9 nymphs, BVI, Carval Rock Is., between Cooper & Ginger Is., 6.X.1999, W. Lu. NMNH — 1 male, BVI, Guana Is., 9-30.X.2000, W. Lu, Malaise trap ; 1 female, BVI, Guana Is. , nr Sugarloaf Mt. top, 806 ft., 7.X.2001, D. Perez. VIIS — 1 female, USVI, St. John Is., 1970 ; 1 female, USVI, St. John Is. , Lameshur Ranger Station, 23.XI.1958, C. F. Adams .

Figures

Figures 4–7. Blaberidae. 4) Colapteroblatta sp. 1 nymph from Tortola Island. 5) Hemiblabera brunneri male adult from Guana Island and nymph from Little Thatch Island. 6) Panchlora sagax from Guana Island. 7) Pycnoscelus surinamensis from Guana Island (all specimens in BDVC).