SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '07815130b9dc64534fbe078bf7daca2219f04672707a0ba2c9fbb6d1ab7ffa99' 
  AND token = 'fM3Zzu6n4htNAMHTQSBZdnU5mJyJOKGKbmxMLXDM1wA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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