SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '69b72d3fd3350fcab614a5f97e151d1e5b07cd94e267c72f46fcd3cfe438eb09' 
  AND token = 'Zjzpb7Xe8HlVQPHE5NdOKEdVirXLzy8gpvxGJ+lC7cI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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