SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cc723ac213cb9803b6b494080db0572903ad51bbdebfacbcc7cc05f0e1bbe39d' 
  AND token = 'BYbkHLMvnvw90TrHHQVWAOqjoIdBwE0ZskmkXrCbDpE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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