SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '63a66e29b5fd74620b33a9a347c4aa2dfa2554fb606bc8fba7a3990a4776c10d' 
  AND token = 'aaRcWYWZVtHW0jJTVvjk/MZrVUdzgNCkXdwFB9KDPNY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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