Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8b6c7c61881d82e59cfafad63fa32322bbb94c1ef9a35bdb508caee1c273c689' 
  AND token = '/DKPFaCB3b+y3Bp1YayZn3VxHqV4yV4TjiW8ZwUtWpQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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