SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '807482b5fdc45f6b4494892bc11c10b30dff6646df7cce059d6f4930da27cb52' 
  AND token = 'GzfHUhbvhQskpGSFXJqfgZG7kiYoQe+JOooVb4fw2yg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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