SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '71fcbc161187851829c15efa4be8bb04da1b6e040b7b29df78b82ba55ec86133' 
  AND token = 'sPY6q+JJNgBVx9caC9lwfrEOQwzeWb3191DlKsPaxWw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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