SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'f2fa6c1139b186693fe089b6c8854d211bf0c88394c6f1c735ca81bda2ab1b69' 
  AND token = 'it2c0Po72uax9nRvodbY807erw/EpZu6yrgSyAEj8fg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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