SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '2d3509caff0a4008a7b0fa0709af389b588c94f78c88089b16bdcea42eddfae5' 
  AND token = 'ooa2f1N/SZYlUlrF3PCvjLNCD+7fu5uF0IIddCLpJy0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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