SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e7e3be4571097109ab44fc635b6a75ad424b8ddb038b6ebf50ab912aa095e74c' 
  AND token = 'yGekIMZHANFIiLYiNIVkQF1CHIp0nFaCrhYZaud4bzc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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