SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7a07b98e31c2c3943e29095a7a114b964c6dfa0f74c3821e5c3bb1d3ff6fb66d' 
  AND token = '3cXHWlbCSmwrdZ+RnZu+twAd2cNKPRoQNHylZpQPzi0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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