SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a02d88f6baf94081bdde6b68686eef514d58698027508cb0a1ade12af6afa113' 
  AND token = 'NAmk1ph5QfjJWR7M9Wik9qmG0EbrM38HaJ5mTxkvDMw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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