SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd4369deb2cf0ac154619182de7dff27c743c7aff3ee5fd09b81ba7693b76178f' 
  AND token = 'bCqi9vWI/5+rsqf1l3ddZUQwo9NL2ROzzg7j7YQnmPc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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