SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '50d21832ef55eba80107257409a8677d02f67abb5646a365682d50dd16c662af' 
  AND token = 'L8r5+PHEx/oLw1F98W+WcVkq9qL1zVErJoIEAyst5qc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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