SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2fc36d3ece4a6221f4cd67ab58be9c8378721e3fdd977b28aacdab00c3b0bf4e' 
  AND token = 'cCJLGGp1bDdvavoYsRw3ayK9sWg8vbLag8mOS59dZ+o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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