SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0da0e5f3e0157caf9a7fa6673d43d3de5706b0fe8fcc55836f04a9230c68d9d8' 
  AND token = 'qk5YvBH0MsFFfAYok311u2bJl+ZZ+9+5VIKQpvb096M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00055

JSON explain

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