SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1f6f9d73be775e1e73b4ea0df7d03b1ecf6f090746b32eb68bf67d0c70e6465e' 
  AND token = 'yrVU8htGaNgaqE/ZJPrc/lPcFKlejNpRzc2Mqs+kTvU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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