SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9b2c7169371becd8b14c75f8d952d04a344b2b6a95ca23093d6fe602a1355cb2' 
  AND token = 'ZH3zD3WQcVeNBOf20WR4Iv+wELt5BPXGfUN0DqecVl8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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