SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '582f9d5989688f7e41438dbde7fc9dcc91cd4ea2b6a6ed7b7917add19161f1a7' 
  AND token = 'vD136LsZbwzafuXcylfxhNRxuZWgPPZS60zgl6TMxZc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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