SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'de7cc6f5672ea042671c76649e73e46c7d39e8cea32fad2ac3f659887a5115f5' 
  AND token = 'Zhnc3/OutggxKrmO2aOGShLYjKU28VaiTM1toE2EC9c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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