SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c8dfc07cf7a21ac03640dae66291cc2eabdd9e666c133c92d51b0a3b6178db12' 
  AND token = 'SzpIcgYSPCM5d9uHW/ZRPF66HzW2bp0MMy7yeEfrQTc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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