SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '12bdcf5d54d9a5ecd5abd15c0d645fc58c2e6e6ca761ff369271f27994f61e4a' 
  AND token = 'F4oxockDMSJ8O8XGyEkZzMUO16Za4AAQxgNp6hidt90=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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