SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '25dcda7655588c4278c909341c099ba1b7e156652dafab3a69003c4175b59e02' 
  AND token = 'aBvwG9DEi1P1SdA979WBXOek424lbUnyYjpMA1lB5bU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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