SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1f705f8de0444882a2b8997a6a4d45359ad050880e89f786165aae251851584e' 
  AND token = 'RQ69GKtunG1DjlmojviCZZF5JtJwBW+S6AD6gj9fGmY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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