SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3bfdd80aa079ab18a7957618f2ac55c0d59509ae79cd005357a48a482fd56ecd' 
  AND token = 'INVeMiW5f8feYsvwsL93GpSy48iebIbp3J4BjPQh0gU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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