SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'badad9f279b01785cd08a1a400e40f0e740f3f690a1dcd4ac580bd077dd76390' 
  AND token = 'UXj9cSYo07GFW2kxvO1hZkI1pZ+Bocc+Sm21GV9givI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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