SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a91086231edbb2f3c03a15c0ec31705e3e6fd79068a4d7a2bf2a90cb22e04a95' 
  AND token = 'kOwgfuzreXg+aJbjCXUufTAAZElIDIuLUMVgc4JQjCQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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