SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '533d5391b3459387f9fd9cde6526e7f1ec5914722ae9979e7fbf7bbfb673f36e' 
  AND token = 'oL4d6vJ8qNXl5ynaFS8lUI797+VBb0EnNKqWizbF2Ms=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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