SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '69ed7cce242a0ee5f8a62b190769b3d320717e28bc12b3348c134395b979c3a9' 
  AND token = 'MFQeUl5B6pckifeS54KxDH21uwBdprk4VE6RtvLkYtw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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