SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'a12ef67390f2eeaaa7fe9eafafb20fb45883a41409b3f4913b18a4d4dc315358' 
  AND token = '4j7zkkP9sokQadbUxERRtVIvWPme8r/ptmpgWKdEhks=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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