Pellaea stictica - a rather attractive and distinctive stinkbug species - seems to have experienced a spike in occurrences throughout SoCal during the past 6 months or so. In fact, it appears the first SoCal record of the species in iNaturalist comes from as recently as 2019. P. stictica is widespread and apparently very well known throughout Latin America, particularly in South America, and may well be on its way to being more common in the southern US. (Its first record in Texas was as recent as 1984.) The life history of the species available (in English, at least) via the internet is pretty sparse: some sources describe the species as an inhabitant of rocky canyons. Individuals of the species can be quite numerous at times, and may frequent plants in the nightshade family (Solanaceae) as well privet (Ligustrum), suggesting expansion in the US could be related to the transportation of landscaping plants.

References:
New data on Pellaea stictica Dallas (Heteroptera: Pentatomidae) in South America. Mariom A. Carvajal, Catalina J. Vargas and Eduardo I. Faúndez. Revista Chilena de Entomología (2019) 45 (3): 419-424. https://www.researchgate.net/publication/335058295_New_data_on_Pellaea_stictica_Dallas_Heteroptera_Pentatomidae_in_South_America

New United States Records For Two Heteroptera: Pellaea stictica (Pentatomidae) And Rhinacloa pallidipes (Miridae).
Thomas J.Henry. Proc. Entomol. Soc. Wash. 86(3),1984,Pp.519-520 https://research.amnh.org/pbi/library/0863.pdf