SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '679face067b37c71779b3c15bea071d46e673946b38094804bf2d518f7ac4131' 
  AND token = 'bbCjJigNvE27E76IdMZ0VonRaxa5bYgmwwbcoV4aqPg=' 
  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"
    }
  }
}