SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a1afd435f561ca748e8a6e5b7da237fa9cec78ca123a1a3d46c75cf7aa1287b1' 
  AND token = '0oPgi24efk45VRQi+GHaJo6hTPpijZCjp0t9ddLfmUs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}