SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1000476e95493a96da73fce9b1e7f255d18f0c1127b37299825c770201d06feb' 
  AND token = 'tMXR34n8WTqIo/YKDRszuKPriqt5Bnj9D39980sdD+g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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