SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '833ebf592c20afbfe93282be8b5baa6b96038ac15d8474e72b99a2a77b68a82d' 
  AND token = 'F7O4DCiER1o2N16WbipoOaJKCd+c7WjW3X3wkK3KOVw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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