SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '34623e32de23cb8c6bc5e9164f02e5fd56f2b1a4d4837a945df5cd61cc8c4ce2' 
  AND token = 'wzqAy1ry9sXnJMKHVQlWr9r9BgtHFxl209hEWQ+0h1I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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