SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '6652526f89aad837c55c5c645e6ad825798e2e0051100acfc0c28b0398d817b2' 
  AND token = '9dmfo2TbLpBExtv3jkwXV/msdpK6Ftma/E/K6LIbk8U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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