SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '044c78624150d27ac582c58490a64bcad46fbbb579e983974739b15f29cb1b4b' 
  AND token = 'ipBzuPEm2TQlnjZivX2ndYoeKRUZGTmWE/2a6LzvrsE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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