SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4f41af5e221eb8c5c8cc551c32b58729f9fa60a9961614e8cb2de5e6704709ad' 
  AND token = 'LA8t0H8YlvBCTNg1MbrNMrkXo9aHcKSy0rkXrl2dePI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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