SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd7bab8147b71d2530c5dec113be85093c626224cbea7a0de1c450f0e32638dba' 
  AND token = '/+evmRUZ5oLN3nNu5cIUACTdarTR3nQpRDUecVWdZIU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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