SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'b11fc5470ce6d667b743764f736d012cfd023969da17f22d2a1f2595f3d2f9ca' 
  AND token = '7SkkWBkOJ1iPTj967WpG+gcAC17mGgJLKoD0yhs+PF8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}