SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3fe080a54bc64506370bd9065b8fde01aa9ef2024f96813a1538a162472e764d' 
  AND token = 'gO06mzoMQFMgoXF2BvmiftSovYkmdEdBHBWaxCsHJHw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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