SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ba3e0f8dae8f7b3556d693aa9ea54d70bb5f21153f43d0c48b4be264146e213d' 
  AND token = '05lKlYZynU43wV9k/BHg58hqAZzFL4rjN4QIJyO+akU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00054

JSON explain

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