SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e70015315931dcfb91de9621afc6643af6d60d629ca59bcce5c30ae743ce5dc3' 
  AND token = 'wWAlwE0kukYVF87kvfWxQeE3JuB6xH8XJUZ2m1IjKaw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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