SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'de30844617acc7e67e5b3fc4430f31258934bca3d9cd77931f689799db34489d' 
  AND token = '+Ixe3yGKi0Cco4jBzjNYJcnIyUGUylR/59b0dp/6uf0=' 
  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"
    }
  }
}