SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '13a6005574105fb7d536f9ee72cc5265c30aa28890a9c7c73c62581092b7924f' 
  AND token = 'YtAZOOVtVyL1g4ikxk2v61OxcVvbmZVrMH+wOZye+mY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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