SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1f516bafdf6ff178aaca3809fc7ae52a5549e4db1b5318d162627b514b2f814f' 
  AND token = '/NWJu3jvYKx2tGGzFY9s4abVTVUx3qBob8Oo0VW5FDo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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