SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'acd80f5f7218e7122084f97291e85de84e18d3539a9d2c8a152a32f66c813d3b' 
  AND token = 'fT4+IWUQ/fQjgSpwVxlmaTkuIF7NeVpWphbjE+5SnpU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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