SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '36dd4232f5e2dc965cb977da7c8293831077556281db871f7496111e7a9d9a62' 
  AND token = 'o911tN3HUsg3cfqRMP72poFIbbu/aleuVE1p/piLe3I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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