SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '02c2dc0d5a490589b741406ec3b0da2551a9d799ba2934cb2e2f0dc6cb1e6ae6' 
  AND token = 'YLYD++QluABgzFIBizDnId28dmZo3JUMkFSzcn8CpgI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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