SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9c24d3391aa1673b79dde0a3d7bd0672309284c9c9af731d95a9759c5e43465f' 
  AND token = 'lr+7ML/Yb6ZfKGzOtCD/9imNil6DBt1dUdxmpkAzRw8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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