SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '06fd31e7ba4d552cd9bb827b7524e9e31e126216026a6839f37c17f336fa500b' 
  AND token = 'Per95zReQfVhgsKj3uSSZoiBUOs6SmH/TYtrP7cxqTY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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