SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b64cb9e33f1a82759e2c659202811a435769d93529814e3fe17dc938378c82ad' 
  AND token = 'sQcDaH7R6xiu51xNtqR7IUo09nKA/zYtLymarna8b4Q=' 
  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"
    }
  }
}