SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9a84c658e3148abd9d4e83b46e0af994118a794dca34e556a2211236e07b7712' 
  AND token = '4uYhcVbPX39WZMigqhj1nbjjGzUX5XTKnuZE+zBHNgw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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