SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '927be4b9fc231975ab84acbe59e66c6aed6397522e9efc82ffdfbe9ccce2d662' 
  AND token = 't3JhvYTiY6oz1oojspMQS57vjg7MBjN9IN1p3xUVFPU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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