SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '1afaaf85f4b7deaf81f09149fcbb6fea80c10038a668bafa2d49065e0a447949' 
  AND token = '7Z+fHflgOupms9sEO+sTUMt2Mw/3nMwzd5B1AonqEA8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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