SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8783a1b03e57c8feeb4a764705e50486821c642ac4fcc9c4294a1bfc1f24b30b' 
  AND token = 'BIksaggUra7w6+/yezZbH1AbQx1Wmay7Jr45Cuj50Jo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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