SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0fcc43ce85f406606187856c2a369e9a20abe4973bb96845450d85761c1a65c1' 
  AND token = 'ImvjvUJBHGyRk38iNrT+8VNUpU5YaJQ3LOUPKmxgItc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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