SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '5ddf629a4e166664bddcac09308fb7002731c508f25fe48862e43aee73ee1bc9' 
  AND token = 'b95gyrc54Am+XAZdK13G6HO0zav03LwzBX2wL+v6NhU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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