SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '067a6e9c38c93a1ad7914e60e471ce050342b0a4446761310a1289763be684d6' 
  AND token = 'C+xbZAazMrHfEXIcvJhz7HDynRRBC7Ix8XCkyY79XEg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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