SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd3665b044cf6054c9bc1dc90b18e65993ecf4590ee48d78cd29c13afb6f0170a' 
  AND token = '72bwWWlJB46d9fEXvIu6eeAllvjCQDETvrOLmVVa1Yg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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